The Processes of Evolution — and their spiritual meaning
The Way of Continuing Creation is based on Nature, Reason, and Science. For our Spiritual Practice of Continuing Creation, the Science of Evolution is the most important of all the sciences. Not because it is the most fundamental (physics and chemistry are more fundamental), but because humans so clearly experience and participate in Evolution.
This Book of G>O>D> already contains an Essay about the Theological Forerunners to Our Spiritual Path, including Taoism, Deism, and Humanism. But this present Essay on the scientific Processes and Principles of Evolution is likely a more important forerunner that than any of those philosophies. Evolution is the science that most clearly demonstrates the Processes of Continuing Creation: The Growing> Organizing>Direction>of the Cosmos.
Definition of Evolution
According to the Dictionary 1 the word “Evolution” has two definitions, and we concur with both of them:
- The process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the Earth.
- The Process by which something gradually develops, especially when it develops from a simple to a more complex form. For example, “The forms of written languages undergo constant evolution.”
The Book of Continuing Creation defines “Evolution” very broadly. For us, Evolution is any process or system (astrophysical, geological, biological, cultural, or technological) that combines parts to form new and different “wholes” that can survive effectively and efficiently in their environments.
When most people think of Evolution, they are thinking of Biological Evolution, and about the evolution of different species in particular. Biological Evolution is defined as the process by which successive generations of organisms change and develop from their ancestral organisms.
But simpler kinds of Evolution also took place in astrophysics, in geology, and in chemistry before life evolved, and they still happen in those arenas today. An example of this simpler form of evolution is the chemical combination of hydrogen (H2) and oxygen (O) to make water (H2O). Another is the chemical combination of sodium (Na), a metal that explodes on contact with water, and chlorine (Cl), a poisonous gas, to make sodium chloride (NaCl), which is common table salt – a compound that is necessary for human life (although many modern humans take in too much salt with their food). 2
Our broad definition of “evolution” also covers cultural and technological Evolution.
An example of cultural evolution would be the creation of the English Language from the intermingling of Briton, Anglo-Saxon, and Norman French. An example of technological evolution is how telephones have changed over time to become cellphones.
The invention of the alphabet was an early and critically important example of technological evolution. A NOVA television (September, 2020) program called A to Z: The First Alphabet describes this with marvelous, filmed illustrations. It shows how the earliest pictograms described things: a picture of a bull meant “bull.” Next, (for example in Egyptian hieroglyphics, ancient Sumerian, and ancient Chinese characters), the picture of a bull could stand for other spoken words that sounded like “bull.” Still later, a stylized bull symbol could indicate all words that starts with a “bu” sound.
Finally, as seen in an early combination of Egyptian and an ancient Sumerian dialect found in the land of Canaan, all words beginning with the “B” sound would begin with the stylized bull symbol. This symbol was followed by a chain of other stylized symbols, “letters,” for all the other sounds in a word – baby, butter, born and so on; following what we today call the Rebus Principle. Together, all the letters would equal an entire word as it was expressed in human speech. In this way, modern alphabets and writing were invented. They evolved through human agency. Sight and sound were combined. Seeing and hearing could now be translated from one to the other.
Our experience on Earth is that over the long run, the Processes of Evolution frequently result in greater organized complexity.
This Essay draws on three earlier Essays in the Book of Continuing Creation:
- Patterns of Information – How G>O>D> Works, because Complex and Evolving systems are active patterns drawn through time.
- Mathematics and Continuing Creation, which explains how mathematical shapes found in Nature, such as the circle and the spiral, arise from engineering principles governing the construction of Earth’s life forms.
- Complexity and Continuing Creation, which describes the set of processes within the science of Complexity (such as emergence, hierarchy, feedback, and chain reaction), which are at work across all the evolutionary arenas of Continuing Creation.
Preview of This Essay
This is the first, and most important, in a series of essays on Evolution. It will lay out many of Evolution’s main Processes and Principles, though by no means all of them.
Later Essays will recount the history of Evolution in more detail, including an Essay on the origin of Life.
In this Essay, we will first tell several historical stories from evolution, and then draw out the Processes and Principles that we find in them. The stories we will tell are the Evolution of the lightbulb, the eye, the lung, feathered birds, the bicycle, the beak, the English language, and the wolf pack.
The Processes we will find include differentiation, combination, mutation, selection, adaptation, replication, reproduction, exaptation, group-selection, and many others.
There are also a great number of biological processes that work to maintain stable functioning (homeostasis) in existing living systems and ecologies. These include respiration, circulation, digestion, photosynthesis, reproduction and many others. However, these are not evolutionary systems, because they are generally trying to prevent change, while evolutionary systems are about creating change. Nevertheless, all these will have occasion to speak briefly about a few of them in the Essay, because these homeostatic processes maintain all the biological platforms, or “canvasses” on which evolution creates its cornucopia of varies living forms and species.
The Goals of this Essay
This Essay aims to achieve the following things:
- Readers will come to understand that most of the Processes and Principles of evolution are basically the same across the arenas of chemistry, biology, culture, and technology. (They are also present in astrophysics and geology, but we will take these up in later Essays.)
- Readers will gain greater understanding of the Processes in Evolution, including Synergy, Emergence, and Complexity.
- We hope readers will see that all the interrelated Processes of Evolution are so evident, so creative, and so beautiful that they support and inspire two things:
— Personal experience of a transcendent Spiritual Path, and
— Active personal participation in the Weave of Continuing Creation.
Reviews of Synergy, Emergence, Complexity, and Transcendence.
We have talked about Synergy, Emergence, Complexity, and Transcendence in other Essays. All of these concepts are interrelated. We can put them all together in one simple sentence:
Synergy causes Complex systems to Emerge from simpler parts, and since these systems are greater than the sum of their parts, they are spiritually Transcendent in our minds. 3
Let’s quickly review these four concepts here:
Synergy is the interaction or cooperation of two or more substances, things, or systems, to produce a combined effect greater than the sum of their separate effects. Processes of Synthesis yield Synergy.
Synergy makes wholes that are different than, and in some way greater than, the sum of their parts. This is the essence of Continuing Creation.
Synergy is Emergence
When parts combine Synergistically, they form Emergent wholes that are different from, and in some ways greater than, the sum of their parts. Emergence is a phenomenon in complex systems where interactions produce effects not directly predictable from the subsystems. 4
Example — The bicycle emerges from the interactions of its wheels, gears, chain, pedals and frame. None of those individual parts can do what a bicycle does as a whole.
Example — Money is not a physical thing like a dollar bill or a gold coin. Instead, money is a shared concept of value. This concept of value emerges from the mutual trust of the individual and institutions who use the money. 5
In complex systems, change is taking place in real time. Not only is the whole more complicated and usually more meaningful than the aggregate of its parts, but the behavior of the ensemble is not predicted by the behavior of the components. In fact, the behavior of the whole cannot even be adequately described by the behavior of the individual parts. 6
For example, the human brain is composed of trillions of specialized cells called neurons. None of those individual neurons can think. It is only when those neurons are combined
and interconnected by trillions of fibers that the brain, as a whole, can think.
Complex Adaptive Systems include: climates; cities; firms; markets; redwood trees; governments; airplanes; industries; ecosystems; social networks; power grids; animal swarms; computers; traffic flows; social insects (e.g. ant colonies); the brain and the immune system; the living cell; the developing embryo; and the electric grid that powers our lightbulbs.
Since all evolutionary systems are a type of complex system, Synergy and Emergence are also present in evolutionary systems. Evolutionary Systems are those that have evolved, and those that are still evolving.
The distinction between complex systems and evolutionary systems is that the latter try out alternatives, or variations, from which only one or a few are selected.
In biology, where the evolutionary process of Selection is done by the surrounding ecosystem, we call it “natural selection.” When human decisions are involved, we call the selection “peer review” in science; “market acceptance” in economics, and “settled law” or “regulatory approval” in governance.
We’ve said that Evolution is a process of Synergy – wherein the Whole is greater than the sum of its parts. Because the Whole cannot be accounted for by the sum of its parts, the Whole is Transcendent. (“Transcendent” meaning “beyond or above the range of normal human experience.” Awe-inspiring; having great and unique significance; sublime.) 7
At least, we human beings experience a feeling of Transcendence, or awe, when we comprehend these synergies. When people have a Spiritual Experience, they are experiencing – directly apprehending and appreciating — the transcendence of the Whole. They are stepping away from analysis (identification of parts; finding cause and effect) and experiencing synthesis. Transcendence is a feeling of deep and wide connectedness with life and Continuing Creation.
Since our human minds are able to extrapolate and plan, we can envision a desirable endpoint. Our transcendent experiences often include possible Emergent Wholes that we extrapolate from our experience in Nature, culture, and technology. We are able to plan new Wholes that we can help create in the future.
There is something inspirational about Synergistic, Emergent Processes. When simple parts combine to make wholes that are utterly different from the parts, that do things that the parts could never do alone, when the Whole is functionally greater than the Sum of its Parts, then those are Transcendent Wholes.
Take, for example, any mental image or thought – the image of a lake, the meaning of a word, a calculation, an emotion — all these thoughts are Emergent phenomena in the brain. We often call the sum of our thoughts “mind.”
Our Spiritual Path of Continuing Creation is Transcendent because the entire Process of Continuing Creation, the “Process of All Processes,” is a miracle. The miracle of Continuing Creation is the only true miracle that has ever taken place. And it is still talking place.
When humans participate in building new things, new “wholes,” we call this guided or agented Evolution. When we do this, we enjoy a transcendent experience of Creating. Creative experiences are always to some degree transcendent for humans. A “bolt of lightning” story is not required. Transcendence, and therefore spirituality, happens all around us within the Processes of Continuing Creation. We need only to perceive and participate. Simple examples include designing and planting a garden, finding ways to reduce your carbon footprint, and helping your child prepare a “science fair” exhibit.
The Transcendent experience can be enhanced and/or made a regular part of life through meditation and mindfulness. For more about Transcendence, Flow, Meditation, and Mindfulness, see our Essay, Leading a Fulfilled and Happy Life.
Note: Poetry is created by Guided Evolution. Poetry is intended to be transcendent. There is a book about cell biology that, while written by a scientist, is so beautiful that it might as well be transcendent poetry. The book is Lives of a Cell: Note of a Biology Watcher, published in 1974 by Lewis Thomas. Here is a quotation from the preface of the book:
“Viewed from the distance of the moon, the astonishing thing about the Earth… is that it is alive. The photographs show the dry, pounded surface of the moon in the foreground, dead as an old bone. Aloft, floating free beneath the moist, gleaming membrane pf bright blue sky, is the rising Earth, the only exuberant thing in this part of the cosmos… If you had been looking for a very long, geologic time, you could have seen the continents themselves in motion, drifting apart on their crustal plates, held aloft by the fire beneath. It has the organized, self-contained look of a live creature, full of information, marvelously skilled in handling the sun.”
Finding Spirituality on the Path of Continuing Creation
There are three ways to find Spirituality through Nature, Science, Culture, and Technology.
- First is to experience Nature directly, by sitting next to a babbling brook, watching fireflies at night, climbing trees. Piloting a small airplane is a direct experience of technology. Attending a ballet or a football game is a direct experience of culture.
- Second is by learning how the Processes and Principles of Complexity and of Evolution are common to all living things, whole eco-systems, culture, and to technologies.
- Third is to participate in the Processes of Continuing Creation – by raising plants, building an airplane, improving technologies, making art, teaching the young. The most
popular videogame in the world is Minecraft, which does not involve shooting or blowing things up, but rather enables players to build and creatre. Stonehenge and the great Catholic cathedrals of Europe inspired craftsmen to build them and awestruck throngs to attend them over the centuries. These structures inspired Transcendent experiences for the workers who made them, and still do so today for the people who visit them. (For a superb architectural and cultural history of two great cathedrals, and the contrasting masculine and feminine spiritualities they represent, see Mont St. Michel and Chartres, published in 1904 by Henry Adams.)
Note: Children have direct experiences of Nature, Culture, and Technology that is evident in their love of pets and stuffed animals; songs and storybooks; and constructive educational toys. Children have an innate capacity for wonder and awe.
When Continuing Creation is experienced in any of these three ways, it generates a feeling of transcendent spiritual connection to Continuing Creation as the Whole of All Wholes.
Taken together, the interrelated processes of Synergy, Emergence, Complexity, and Evolution comprise the main pulleys and levers of Continuing Creation: The Growing> Organizing> Direction of the Cosmos. This is particularly so when we experience the processes of G>O>D> working around us here on Earth.
Thomas Edison and the Evolution Electric Light
We began our Essay, Complexity and Continuing Creation, with an example of the lowly but beautiful slime mold, describing how individual slime mold cells come together when food grows scarce to temporarily form and work cooperatively as a single organism, giving us a wonderful example of the Emergence Process in the Science of Complexity.
We’ll begin this Essay on the Science of Evolution with an example from technology – the evolution of Thomas Alva Edison’s incandescent lightbulb, patented in 1879. We’ll tell this story in more detail than we do the stories after it, because we want the reader to see the many steps involved in a typical course of evolution.
In school, most of us were taught that the lightbulb sprang into existence as the sudden result of Edison’s inventive genius. Not to denigrate Edison’s work, but the Guided Evolution (invention) of the lightbulb actually drew on earlier knowledge and technology created by many other people – known and unknown. Here is the full story: 8
- A person or persons invented ways to supply electricity — from a battery or a generator.
- Someone(s) invented the way to transport energy – through copper wires.
- Someone(s) invented a vacuum pump that could evacuate the air from a hand-blown glass bulb.
- In 1802, Humphry Davy connected a battery and wires to two carbon electrodes. The electric arc jumping from one electrode to the other generated light. But this light was way too bright for practical use.
- In 1840, Warren de la Rue connected the two wires with a coiled platinum filament. The filament glowed with heat, giving off adequate light, but platinum was prohibitively expensive.
- In 1850, Joseph Swan used carbonized paper filaments, but the vacuum pumps of his day could not create a sufficient vacuum inside the bulb.
- In 1874, Henry Woodward and Matthew Evans filed a patent for a bulb with carbon rods held inside a vacuum bulb.
- In 1879, Edison improved the carbonized filament and the vacuum pump, and patented his bulb.
- Swan incorporated Edison’s improved filament and founded an electric lighting company in England. Also in 1879, Woodward and Evans sold their patent to Edison.
- Swan then turned his attention to producing a better carbon filament and the means of attaching its ends. He devised a method of treating cotton to produce ‘parchmentized thread’ in the early 1880s and obtained British Patent 4933 that same year.
- Edison and his team later discovered that a carbonized bamboo filament could last more than 1200 hours.
- Edison sued Swan for patent infringement. Eventually Swan’s firm was merged with Edison’s to form Edison-Swan United.
- In 1904, Hungarian Sándor Just and Croatian Franjo Hanaman were granted a Hungarian patent (No. 34541) for a tungsten filament lamp that lasted longer and gave brighter light than the carbon filament. 9
- In 1906, William D. Coolidge developed a method of making ductile tungsten which could be made into filaments while working for General Electric Company (GE). By 1911 General Electric had begun selling incandescent light bulbs with ductile tungsten wire.
- Around 1913, General Electric started coiling the filaments in bulbs, and began filling them with inactive gases such as argon and nitrogen to slow down the evaporation of the tungsten. This also allowed for greater temperatures and therefore greater efficacy. 10
- 1900’s – invention and commercialization of the electric neon-tube light for neon signs.
- 1930’s – The mercury-vapor fluorescent light, known in the late 1800’s, is commercialized by General Electric in the 1930’s.
- 1968 – The first commercial LED lamps are introduced.
Historian of technology Thomas P. Hughes attributed Edison’s success to his development of an entire, integrated system of electric lighting:
“The lamp was a small component in [Edison’s] system of electric lighting, and no more critical to its effective functioning than the Edison Jumbo Generator, the Edison electric main and feeder, and the parallel-distribution system. Other inventors with generators and incandescent lamps, and with comparable ingenuity and excellence, have long been forgotten because their creators did not preside over their introduction in a system of lighting.” 11
For a general reference about the invention and commercialization of the electric lightbulb, see: https://www.livescience.com/43424-who-invented-the-light-bulb.html.
Evolutionary Processes & Principles from the Story of the Lightbulb
In the above example of the Electric Light, the following Processes and Principles of Evolution are at work:
- Process: Guided Evolution – Guided Evolution is any cultural or technological progression that is guided by the minds of human beings. The inventors of the lightbulb were also the managers of its evolution. Guided evolution occurs first in the human mind, and only later in physical things. Guidance gives a much faster rate of evolution than we nearly always see in Nature (Although viruses can evolve with speeds equal to most human invention.) Some fundamentalists speak of “guided” evolution meaning “guided by God.” We are not. We are talking about Evolution guided by Humans and following the laws of physics, chemistry, and biology.
Humans are not the only species that invents; not the only species that has evolutionary agency. Birds build nests, and therefore some ancestor of the dinosaurs that were the ancestors of the birds must have invented the nest, the burrow, the “structure.” Beavers build dams, certain ant species farm and milk captured aphids. chimpanzees and crows use sticks as tools. Their young learn this skill from their elders. Crows can even build compound tools out of multiple parts. 12
Principle: Invention Is Really Evolution – School kids are taught that Edison invented the electric light. But our story shows that a number of different inventors worked on this technology. We could even say that in the late 1800’s, humans were “destined” to evolve the electric light. By that time, the knowledge of electricity and electric technology had developed to such a point that it was highly likely that humans would come up with workable electric lights; and further, that a commercially feasible system of electric lighting would not be far behind.
- Variation-Selection Process – In the electric light story, the inventors come up with variations in design. Edison and others tried scores of different filaments in the bulbs. The selection was done by the laws of physics, by the inventors, and by the marketplace. Together, they were looking for filament brightness, endurance, and a low cost-to-produce and install. We can say that together, the laws of physics, the inventors, and the market were the Environment that did the selection.
Note: Professor Armand Leroi, professor of Evolutionary Biology, writes that all Variation-Selection systems are generally described by the Price Equation, developed by George Robert Price in 1970. This equation demonstrates how changes at a lower level make for changes in an upper level of an organized system. 13
- Process of Mutation and Natural Selection — In Darwin’s On the Origin of [biological] Species, (1859), the variation-selection process becomes a mutation and natural selection We will talk further about natural selection later in this Essay.
- Principle: The Selection Process is not random. It is a function of the lamp’s brightness and hue as preferred by humans, the length of the bulb’s life until burnout, and the total cost of a lighting system and its fuel on a per-hour-of-light basis.
- Process: Evolution by Many Small Steps – The incandescent lightbulb was not suddenly invented by a stroke of genius. Historians Robert Friedel and Paul Israel list twenty-two inventors of incandescent lamps prior to Joseph Swan and Thomas Edison. Doing many small steps required lots of time. Edison was a driven workaholic, who spent untold of hours trying different filaments and vacuum pumps. 14 Biological evolution almost always takes millions of years (exceptions include fruit flies and viruses).
- Process of Trial and Error – Thomas Edison and the other contributing inventors tried hundreds of different filaments for their experimental lightbulbs. As Edison wrote —
- “I speak without exaggeration when I say that I have constructed three thousand different theories in connection with the electric light, each one of them reasonable and apparently to be true. Yet only in two cases did my experiments prove the truth of my theory. My chief difficulty, as perhaps you know, was in constructing the carbon filament, the incandescence of which is the source of the light. Every quarter of the globe was ransacked by my agents, and all sorts of the queerest materials were used, until finally the shred of bamboo now utilized was settled upon.” — Thomas Edison, The Edison Papers, Rutgers University http://edison.rutgers.edu/newsletter9.html#4
- In biological evolution, undirected mutations of genes (and sometimes receipt of genes transferred in from viruses) produce random changes in organisms. Only a very few mutations turn out to give the organism a useful advantage — a competitive advantage over its competitors for resources, and/or over its predators.
- Process: Creation by Combination – Edison’s invention entailed combining the right bulb components into a Whole bulb that really worked. The first light bulb combined two pieces of scientific knowledge: (1) knowledge that an electric current in a fine wire (“filament”) could make it heat up and glow, shining out light; and (2) knowledge that when such a fine filament was surrounded by normal air, the oxygen in the air would make the filament rapidly burn up. Human inventors like Edison tried placing the filament in a glass bulb and sucking all the air out of the bulb. After trying countless different filaments, they made successful “incandescent” light bulbs.
In common speech we usually say that the bird species “learned” how to fly. It would be more correct to say that one (or a few) particular species of small dinosaur evolved feathers for warmth, then used longer feathers for gliding, and then used feathers further tapered and streamlined by additional evolution for more efficient flying. But it would also be correct to say that early birds and Earth’s atmosphere combined to create artful flying. Can we say that artful, controlled flying is something utterly new and different than anything that came before? Pretty much we can, although flying was preceded by jumping from limb-to-limb and then by gliding from limb to limb. In addition, we can see that flying looks similar in important ways to swimming. We will talk more about the evolution of flight later in this Essay.
- Process of Competition — Edison competed with other inventors, and also with other businessmen. The different bulbs and electrical systems also competed with each other (e.g. Edison’s “direct-current” versus engineer and inventor Nicola Tesla’s “alternating-current”).Over the decades, the various lighting technologies have competed with each other in the marketplace. They competed on the basis of quality (e.g., the hue and intensity of the light), durability, safety, ease of use, cost, and (recently) environmental impact.
Example: In biology, there is competition between deer and elk for grazing territories; and there is competition between wolfpacks for the “right” to hunt the deer and elk on a territory of land. This is Darwin’s classic “survival of the fittest.”
Is competition synergistic? It can be, but only for the next-higher level of Complexity. “Survival of the fittest” helps the species, not the individual organisms that lose the competition. For the most part, Tesla’s alternating-current system triumphed over Edison’s direct-current system. Edison lost and Tesla won, but the major winner was the overall technology of lighting systems.
Example: Two wolves fight over which will become leader of the pack. Is this synergistic? It is at the level of the pack, because it usually reveals the wolf who is most capable of leading the pack to joint survival, prosperity, and reproduction.
- Process: Cooperation – When Swan and Edison combined their companies, they practiced evolutionary cooperation by merging efforts and lowering combined administrative cost. Of course, each party received a financial benefit of their own; otherwise they would not have done the deal.
- Example — In biology, cooperation is often in the self-interest of the cooperating creatures. The mutualism between the shark and pilot fish is a good example. The pilot fish gains protection from predators, while the shark gains freedom from parasites on its skin. Mutualism is a type of symbiosis where both the host and the symbiont benefit from their relationship. Human beings are dependent on a host of bacteria (including E. coli) that live in our guts and perform critical functions in our digestion or in the breakdown of toxins. 15
- In biology, Symbiosis simply means “living together,” at least for a time. Thus, Parasitism is another type of symbiosis, one that occurs when the invading organism benefits and the host organism does not, as in the example of the tapeworm, which “steals” nutrients from the human digestive tracts where it lives. In the arena business, “patent infringement,” claim-jumping, and embezzlement would be parallels to parasitism; but they are not examples of human cooperation. (Carl Zimmer’s 2001 book, Parasite Rex is a fascinating, if at times “gross,” tour through the bizarre world of biological parasites.)
- Processes of Triggering Event and Following Cascade – Although Edison arrived at his bulb through many small steps (taken by himself and by others), once the new bulbs were harnessed to commercial electric generating stations, the combined system was speedily adopted across the country. Biologists would say that the “new species” was “highly adapted,” and rapidly achieved “wide geographic dispersal.” Historians of technology might call this process the “Electric Revolution.” The “triggering event” can also called the “inflection point,” disruption, or “breaking point.” Other names for the “cascade” are “revolution,” “sea change,” and “paradigm shift” usually depending on the evolutionary arena being discussed.
- Process of Dispersal — In technology, dispersal happens by selling new machines into new markets, and this may require adapting the machines to new industries or populations. In biology, dispersal can happen if there is too little game in an area to feed all the wolves, some of them may split off and migrate to a far or isolated location.
- Process of Speciation — If the new location is markedly isolated, e.g. by a canyons or mountain ranges, the wolf population may experience significant mutations and become a new species of wolf. This is one way in which the Process of Speciation happens in biology.
In the arena of technology, direct-current systems will work for a large population close to a central generating station. But to reach and electrify sparsely-settled rural areas, high-voltage alternating-current systems are able to transmit high-voltage current over much longer distances. Near the final destinations, the system then uses local transformers to “step down” (reduce) the voltage and deliver practical electric power to homeowners and businesses.
We could also say that arc lamps, fluorescent lights, neon lights, and LED (light-emitting diode) lamps are different enough from each other that we can, by analogy to biology, call them different species of electric lamps.
- Principle: Hierarchy of Evolved Systems – On the higher scale of business organization, Edison’s success at spreading his invention was as much about combining (merging) with other companies as it was about inventing a commercially viable lightbulb. Incandescent lightbulbs must be connected in city-wide systems of generators, wires, and screw-in receptacles, all constituting a system “one level up” from the lightbulb. 16
Then, at still higher levels, some entity (corporation) must be invented to finance, own, and operate the system. Government must coevolve to effectively regulate the corporations and the electrical systems (including their safety). Today, most large electric utilities are owned by public corporations and closely governed by governed State Utility Commissions, which oversee the corporations spending and have the final say on prices charged to customers. Smaller utilities are often owned outright by the cities, towns, and counties they serve. 17
- Process: Exaptation – Exaptation takes place when a structure evolved for one purpose proves useful for another purpose. The wiring of a house, originally installed for electric lighting, became useful for electric skillets and radios. Feathers, originally evolved by small dinosaurs for insulation and/or display, later became useful for flying by the birds, all of whom evolved from small dinosaurs.
- Process: Coevolution – The household wires powering the bulbs could also power electric appliances, creating a coevolution of mutually-reinforcing development between electric lights and electric appliances. For example, the same power station and the household wiring can serve many end-use technologies, cutting the cost of each one. In fact, the spread of electric power itself became a “process,” the Process of electrification. The use of electricity is now so common that it constitutes an important part of the modern world’s “technological environment.” It is high up on the hierarchy of technological systems-of-systems.
- Process: Homeostasis — In general, homeostasis is the tendency toward a relatively stable equilibrium between the interdependent elements of a system. The term is usually reserved for physiological systems, but can be applied to technologies, economies, and cultures. For decades, electric lighting in the United States was a stable mix of coal and water powered generation, mostly shareholder-owned utilities closely regulated by state utility commissions, alternating current, and incandescent and long-tube florescent bulbs. But starting in the 1980s, the mix has been disrupted by the new technologies of wind and solar generation, home-generated (“distributed”) generation, improving large-scale battery storage, LED lights, and the growing need for a more robust power transmission system.
In biology, homeostasis is the state of steady internal, physical, and chemical conditions maintained by living systems. This dynamic state of equilibrium is the condition of optimal functioning for the organism and includes many variables, such as body temperature and fluid balance, being kept within certain pre-set limits (homeostatic range). Other variables include the acidity (pH) of extracellular fluid, the concentrations of sodium, potassium and calcium, and the blood sugar level. These need to be regulated despite changes in the environment, diet, or level of activity. Each of these variables is controlled by one or more regulators or homeostatic mechanisms which together maintain life. 18
- Process: Differentiation –– Lamp technologies and lighting markets co-evolved. Some lighting technologies were found to be better adapted to niche-environments (segmented markets) than others. For example, neon lights are almost exclusively used for neon signs. Arc lamps came to be reserved for searchlights and film projectors, but lately they have been replaced by xenon arc lamps for those two purposes. Today, the original arc lamp is used mostly for generating high intensity ultraviolet light.
- Processes: Adaptation and Niche–filling – Different types of lights (or species of biological organisms) usually end up in environments that they are well-suited to function (live) in. Arc lights are mostly used – best adapted – for high-intensity ultraviolet lamps. Long fluorescent-tube lights are mostly used in commercial buildings. And neon lights are mostly used to fill the niche of store-front advertising.
- Process: Evolutionary Cycle — The history of electric lighting is a good example of how most technologies evolve: They start with an invention that is new — at least to the public. Then features are added, making the invention more effective and efficient. Thirdly, new and different versions of the invention are created, each with unique features that make it better adapted to a special niche environment. Over time, most of these technologies will “go extinct” (or virtually extinct) in the face of changing environment and/or competition with new “players.” The classic example of near-extinction is the “buggy whip.”
In biology, the cyclic pattern over time is the same – new organism, then improvements in the organism, diverse varieties, homeostasis, eventual extinction. So, we have the early “dino-birds,” then birds that are effective fliers, and then birds that eat seeds versus raptors that eat meat. Earth has not yet seen the extinction of all the birds. As previously mentioned, over the long time span of evolution an estimated 99% of all species have gone extinct. 19
- Processes: Death and Extinction – When each gaslamp was taken out of a Victorian home between 1890 and about 1935, it was like the death of an individual creature. When gaslighting all across the world was replaced with electric light systems, the “species of gaslighting” went extinct. The “electric-light species” out-competed the earlier “gas-light species,” driving gaslight systems out of business. Today, it is possible to see that LED lights may well drive tungsten-filament lights to commercial extinction in nearly all markets, i.e. in nearly all “environmental niches.” (See our Essay, Dealing With Death on the Path of G>O>D>.)
Edison must have felt great elation upon completing his invention of the incandescent lightbulb, and again when he made it commercially successful. This elation is an example of the Transcendent Spiritual Experience we all feel when any of us helps create something.
When we review its history, it almost seems as if the emergence of the electric light was inevitable. If not inevitable, then highly probable, and if not that… at least the evolution seems to have had “momentum.” The feeling of positive momentum is also part of the transcendent experience of Continuing Creation.
The Story of The Evolution of the Eye
Next, we will talk about the evolution of something biological – the Eye – the organ which makes use of technology’s lightbulbs. After the Eye, we’ll recount the stories of the lung, feathered flight, and the various creatures that have beaks.
Again, we’ll pull out important Evolutionary Processes and Principles from each story, those that demonstrate the thrust of Continuing Creation – greater complexity and sophistication, with transcendent Wholes emerging from the organized combination of simpler parts.
Note: in tese next sections, to interleave the steps of the stories with the Processes and Principles that each step best illustrates.
Evolution has constructed eyes in three very different forms, and there are many variations within each form. The three types are Curved-dish Reflector eyes, Compound Eyes, and Complex (camera-like) Eyes such as our own human eyes.
“For each of these types of eye, stages corresponding to evolutionary intermediates exist as working eyes among modern animals.” (Richard Dawkins, The Blind Watchmaker, pages 85-88.)
Curved-Dish Reflector Eyes
Curved-dish Reflector Eyes work like radio telescopes do. They catch light beams (or radio waves) on a rear parabolic reflector, which shoots them back toward a central focal point, where they impact a patch of light-sensing cells. “The curved dish-reflector principle is radically different from our own eye (we use it in radio-telescopes, and also in our largest optical telescopes because it is easier to make a large mirror than a large lens), and it has been independently ‘invented‘ by various mollusks and crustaceans.”
Compound Eyes are found in arthropods (shelled creatures like insects, spiders, shrimp, lobsters, and barnacles). They consist of many (sometimes thousands) of very small, individual, lens-less eye-units (ommatidia) all packed together on a hemispherical surface. Each of these eye-units sees just a small arc of the vision field. We’ll take up compound eyes again later in this Essay.
Complex (camera-like) Eyes
Complex Eyes are the kind that humans have; along with all mammals, birds, amphibians, fish and reptiles. So do the nautilus and the octopus, which are mollusks. All of these eyes let light enter a narrow aperture. The light then travels to strike a screen (the retina) set some distance to the rear.
Some complex eyes have no lenses. They operate like the simple pinhole cameras (camera obscura and camera lucida) that artists such as Vermeer are thought to have once used to project images onto a canvas. The artists would then trace the image onto the canvas prior to painting.
Most complex eyes do have lenses, which focus the images before they impact the retina. D.E. Nilsson and S. Pelger estimated in a classic paper that only a few hundred thousand generations are needed to evolve a complex eye in vertebrates. 22
All Three Types of Eyes Had Just One Origin
Fundamentalist religious creationists have argued that the existence of the eye proves that humans must have been designed and created by God. They would argue, “half an eye would be of no use at all. The eye is an all-or-nothing organ, so it must have been created all-of-a-piece, and only a super-being could do that.”
But it turns out that partial eyes, primitive eyes, are found everywhere in nature, and they do serve a purpose for the organisms that have them. (See our Essay, “Answering Evolution’s Critics.”)
The simplest of all living light sensors are patches of molecules (“eye spots”) are found in certain bacteria, plants and animals. All three types of eyes and all their variations evolved from such patches. Eye spots have evolved independently at least 40 times, and probably as many as 65 times. 23
“Some single-celled animals have a light-sensitive spot with a little pigment screen behind it. The screen shields it from light coming in from one direction, which gives it some ‘idea’ of where the light is coming from.” 24 This allows the organism to turn itself toward the light if it does photosynthesis, or to tell night from day, which signals creatures when to sleep and when to be awake.
- Process of Divergent Evolution – This happens when related species evolve different forms or structures as they adapt to different environments. Some creatures have evolved compound eyes; others evolved complex eyes. Another example of divergence is the development of the arm and paw (or arm and hand) in most mammals, and the development of bones in bat wings, all from the bones in early ancestral fish fins.
- Process of Parallel Evolution – The independent evolution of similar traits, starting from a similar ancestral condition, where several species respond to similar challenges in a similar way. Although the compound, camera-like, and reflector eyes evolved very different “technologies” in different species, they all still achieve vision, and they all still evolved from the early patch of light-sensitive molecules in single-celled organisms. Therefore, we can say that the three forms are examples of Parallel Evolution – distant parallel evolution, but parallel evolution none the less.
- Principle of Deep Homology: Biological Homology is a similarity in two different species that results from their having a common ancestor-species. If the common ancestor-species was in the distant past, the similarity is called a Deep Homology. For example, the eye of the octopus has almost the same complicated structure as the human eye. Since the two species are not at all closely related, (the octopus is an invertebrate, and Humans are vertebrates), that two such markedly different creatures would have similar eyes is extraordinary.
Recent progress in modern evolutionary biology and genetics has shown that most similarities between even distant species results from deep homology. Science now shows that even eyes as dissimilar as the compound eyes of insects are deeply homologous with the eyes of humans and the octopus. Their evolution has been governed by similar genes such as pax-6, from the genetic inventory, the evo-devo gene toolkit. These genes are ancient, and it is remarkable that they can still generate the patterns in time and space which shape the embryo and ultimately form the body plan of the organism. 25
If we consider the sense of hearing instead of vision, we see a similar pattern. Like eyes, insect ears are also remarkably diverse, yet analysis shows that they all evolved from one of the several places on an insect’s body where a “stretch-detector” was located. The original function of all stretch-detectors was to detect and monitor tiny vibrations when neighboring body segments move. Different insects used different stretch-detectors to become ears, and the choice almost seems random. 26
Process of Abiogenesis –
Before leaving the Principle of Deep Homology, we need to tell our readers that evolutionary biologists overwhelmingly maintain that all life evolved from a single species, a “first organism.” This organism is thought to be the original ancestor of both the ancient bacteria and the ancient archaea. The strongest evidence for a single “first organism” is that the DNA of all living things is highly similar. It is, however, expressed in different ways in sexually-reproducing organisms as they develop after fertilization of the female’s egg.
- Note: The archaea are a massive population of asexual single-celled creatures that for decades were thought to be bacteria, until genetic analysis showed them to be substantially different than bacteria.
From Chemical Systems to Biological Systems
While the details are still unknown, the prevailing scientific hypothesis is that the transition from non-living to living entities was not a single event, but an evolutionary process of increasing complexity that involved molecular self-replication, self-assembly, autocatalysis, and the emergence of cell membranes. 28 The Book of Continuing Creation plans to write a separate Essay on The Origin of Life.
Evolutionary Steps Toward the Camera-like Complex Eye
Among the multi-celled animals, we find that various types of worm and some shellfish have an arrangement similar to the light-sensitive patches in single-celled creatures, but the pigment-backed light-sensitive patch is a group of cells “set in a little cup. This gives slightly better direction-finding capability…. Now, if you make the cup very deep and turn the sides over, you eventually make a pin-hole camera. A pinhole camera forms a definite image, the smaller the pinhole the sharper (but dimmer) the image; the larger the pinhole, the brighter (but fuzzier) the image. Just like a pinhole camera, and every other man-made camera since.’ 29
- Principle: The evolution of certain things can be highly probable, given the laws of physics and chemistry and basic conditions on Earth, including energy flow-through (e.g. from a sun), temperature range, pressure, planet size, geologic composition, the presence of water and carbon, and atmospheric composition.
These highly probable evolutions include the ability of organisms to move, to see, to hear, to feel, to smell, and to self-defend. Many organisms are also evolved to explore and to become more complex over time.
Of course, certain things must have evolved, for they are required to sustain life: a metabolism that converts food into energy, the ability to maintain structure and organization for a period of time (the organism’s lifetime), and the ability to reproduce.
A number of mollusks have a camera-eye like ours, or a pinhole camera-eye. Richard Dawkins writes, “The swimming mollusk nautilus, a rather strange squid-like creature… it has a pair of pinhole cameras for eyes. The eye is basically the same shape as ours, but there is no lens. Actually, Nautilus is a bit of a puzzle… why, in all the hundreds of millions of years since its ancestors first evolved a pinhole eye, did nautilus never “discover” [evolve] the principle of the lens?… At least their pinhole eye dramatizes the point that a lens-less eye is better than no eye at all.” 30
- Principle: Evolution of the eye (or any other feature) is not inevitable. No matter how useful a lens might be, if there was no ancestor with a pre-lens, then there can be no descendent with a lens. Just as an eye cannot spring from nowhere, neither can a lens. They both require precursor structures from which they can evolve.
Handling the Pinhole’s Inverted Image
Pinhole cameras and pinhole eyes project an inverted image on the film or retina behind them. Whenever light comes through a small aperture (hole), the image is upside down (because the eye has to follow the laws of physics). This is true of both eyes and cameras. The brain has to turn eye images right side up. In photography, a pair of human hands turns the negative downside-up. (And with film, the image in the film is also in reverse, so it has to be projected onto print-paper to produce a positive image.)
This manual handling of right-to-left inversion is similar to what took place in technology’s invention of moveable type for printing books: Each letter had to be cast in reverse, and set in from right to left in the sentence, so that when coated with ink and pressed onto paper, they would make a readable image that runs from left to right.
- Principle: Technology often emulates natural processes. Human invention follows nature’s path. Lenses for cameras, glasses, microscopes and telescopes follows Nature’s “invention” of the lens. The design of a digging machine follows the basic joint-and-cable structure of a human arm. Why? Because both human invention and Nature’s evolution must follow the laws of physics and chemistry. In doing their work. both invention an evolution often use the same engineering techniques to save energy, resources, and time.
Story – Evolution of The Cornea and Lens of the Eye
We will likely never know the first animals to evolve lenses (or the other parts of the eye, for that matter), because, unlike bones and teeth, they are too soft to fossilize. But the first creatures to have lenses may have been among the early chordates (i.e., animals with a spine or its flexible precursor).
The earliest chordates presumably resembled the modern lancelet – a nearly brainless animal that lacks paired eyes and feeds by filtering food from the water. Evolution then formed
the vertebrate body by fashioning fish with distinct heads, paired eyes, and other features for hunting. All amphibians, reptiles, dinosaurs, birds, and mammals (including humans) evolved from early species of fish. The Devonian Period saw the rise of the first labyrinthodonts, which was a transitional form between fishes and amphibians.
In any case, the transparent cells over a pinhole eye’s aperture split into two layers, with liquid in between, forming the cornea in front of the modern eye’s lens. The liquid originally served as a circulatory fluid for oxygen, nutrients, wastes, and immune functions, but its naturally biconvex shape proved to be an ideal structure for the liquid called the aqueous humor, which refracts the light in preparation for the lens. This fluid, along with the larger vitreous humor between the lens and the retina, also optimizes color filtering, blocks harmful radiation, improves the eye’s refractive index, and allows functionality outside of water by supporting the eyeball’s spherical shape. 31
The octopus’ eye is very like the human eye, but it is filled only with seawater, while other creatures, particularly on land, evolved the transparent aqueous and vitreous humors. The seawater maintains the shape of the octopus eye, but does not afford the clarity of vision that humans enjoy from our aqueous and vitreous humors. On the other hand, the octopus can distinguish polarized from non-polarized light, and may have color-sensitive cells in its skin that allow it to mimic the colors of its immediate surroundings, giving it amazing camouflage capability. 32
Vertebrate lenses are composed of adapted skin (epithelial) cells which have high concentrations of protein crystallins, which are transparent. These crystallin proteins were originally used for other functions in organisms, but eventually adapted for vision in animal eyes. 33
Independently, another transparent layer and a nontransparent layer split forward from the lens: the cornea and iris. In vertebrates, the lens of the eye is directly behind the iris.
In many species (including humans) the eye lens can be thinned and thickened by the pull and push of tiny muscles around the edge of the lens. A thinning of the lens allows the eye to see at greater distance, and thickening makes the eye see things that are close up.
- Process: Evolution in Small Steps – The existence of the human eye might seem like a one-time Godly creation to religious people who have not studied evolution, but in reality, the evolution of all eyes, including the human’s complex, camera-like eye, involved many small steps, taken over hundreds of thousands of years – the light-sensitive spot, the inward curve to form a cup, the membrane over the aperture, the separation and formation of a lens, the humors, the iris, the ability to focus.
Focusing the Lens
Nerve cells behind the eye and in the brain sense whether or not the desired object is in focus, and they send nerve signals to those tiny muscles around the edges of the lens which tell the muscles whether or pull or push on the edges.
Seeing the Image
After light moves through the aqueous humor and the lens, it traverses the transparent vitreous humor behind the lens and strikes the retina at the back of the eye. The retina is where the eye’s photoreceptor cells are located. Right behind the retina are the ganglia – specialized nerve cells which convey the images to the brain by secreting a neurotransmitter chemical into the tiny gap (synapse) between itself and an adjacent nerve cell. The receiving nerve cell does the same thing between itself and the next nerve cell over. In this way, a chain-reaction of electrochemical signals are passed along a network of nerve cells to eventually reach the brain. It is the brain that “sees” the image. Only the brain can say whether the image is of friend or foe. 34
Four common processes found in many complex systems are involved in these eye and brain operations:
- Processes of Sensing, Signaling, Feedback, and Controlling – They are all present in lens focusing and in seeing the image. All these processes arise everywhere in biological systems that have evolved any complexity.
Systems inside the body convey messages and commands by means of electrochemical nerve impulses and hormone secretions. Mammals convey messages to other mammals by roaring, squawking, displaying, dancing, and talking. Human mammals add writing, radio, motion pictures, television, and telecommunications.
Machines send messages/commands by electric circuits, computer networks, and fluid flows. Businesses send messages by means of letters, faxes, websites, and telephone calls – all through and/or approved by their agents. Their agents are their human employees. They interact with outside humans who are agents of other businesses or of regulatory authorities.
- Principle: Information is largely independent of the medium that carries it. In the example above, the image is one type of information. It is carried first by sunlight’s photons as they travel to and reflect off some object, and then by nerve impulses to the brain.
The distribution of photoreceptors on the retina tends to match the area in which the highest acuity is required. Horizon-scanning organisms, such as those that live on the African plains, have a horizontal line of dense photo-transmitting nerve cells. Tree-dwelling creatures, which require good all-round vision, tend to have a symmetrical distribution of such nerve cells, with acuity decreasing outwards from the center. 35
Acuity is higher among male organisms that mate in mid-air, as they need to be able to spot and assess potential mates against a very large backdrop. The eyes of animals which operate in low light levels, such as around dawn and dusk (“crepuscular” vision) or in deep water, tend to be larger in order to increase the amount of light that can be captured. 36
- Processes of Adaptation, Elaboration, Specialization, and Niche-filling – These different patterns of visual acuity show that all these processes took place as the eyes of different species evolved to better fit the surroundings and behavior patterns of each species. In addition, hunting birds such as eagles, falcons, and hawks have the ability to see small creatures as they fly at hundreds of feet overhead. Another raptor, the owl, also has great visual acuity, but its eye apertures are larger so the owl’s eyes can admit more light for hunting at night. 37
Positioning the Eyes on the Head
Another example of the four processes just mentioned, is evident in the placement of eyes on the heads of different mammals. Some animals – usually, but not always, prey animals – have their two eyes positioned on opposite sides of their heads to give the widest possible field of view. Examples include rabbits, buffaloes, and antelopes. In such animals, the eyes often move independently to increase the combined field of view. Even without moving their eyes, some birds have a 360-degree field of view.
Many other animals – usually, but not always, predatory animals – have their two eyes positioned on the front of their heads, thereby allowing for binocular vision. This reduces their field of view in exchange for stereopsis and its greater depth perception. Notably, eyes on the front of the head is a highly-evolved trait in vertebrates, and there are only three extant groups of vertebrates with truly forward-facing eyes: primates, carnivorous mammals, and birds of prey. 38
- Process: Variation-Selection — Positioning of the eyes demonstrates the Variation-Selection Process (which we talked about in the Story of the Evolution of the Lightbulb). The vast, predator-filled environment of the grazing herbivores selected gene mutations that favored wider range of vision. For predators, the same environment, selected (favored) offspring that could hunt more effectively by means of more acute vision and motion tracking.
Processes of Gene Transfer and Mutation —
In the arena of biology, the “Variation” in the Variation-Selection process happens by changes to an organism’s genes, which are the blue print for its entire structure. In the days of one-celled creatures, genes were changed by mutation, and also by absorbing bits of DNA from neighbor organisms, or by having them inserted by “invading” viruses. 39
Note: This Essay does not take up the evolution of first life, of cell walls, micro-organisms (bacteria and archaea), or the evolution of early multi-cellular life. We’ll take those topics up in a later Essay.
Processes of Asexual and Sexual Reproduction –
One-celled organisms reproduce asexually, i.e., by simply dividing in two, with no genetic variation in the offspring. The offspring that arise by asexual reproduction from a single cell or from a multicellular organism inherit the genes of that parent. Asexual reproduction is the primary form of reproduction for single-celled organisms such as archaea and bacteria. Many multicellular animals, plants and fungi can also reproduce asexually. 40
Many larger organisms evolved sexual reproduction, where two members of the same species must mate to produce an offspring. The offspring would have variation in its genes because it had received a shuffled set of genes – some genes coming from its father, and some from its the mother.
Principle: Conformance with Laws of Physics and Chemistry —
Eyes would never have evolved if there were no reflected light. The cavefish in dark underwater caves, in the deepest ocean depths, and even 700 feet down in the Congo River are nearly all sightless. Moreover, most of them probably started out as sighted fish, and then lost their sight through natural selection when it became no longer useful. 41
Principle: Evolutionary Paths Are Probable, but Not Inevitable —
So, sight evolved in response to presence of reflected light, particularly reflected light. Is that evolution inevitable? No. Is it highly probable? Yes, and the evidence is that we know the eye evolved independently in many different animal lines, and the evolution created three very different types of eye – Compound, Convex, and Reflector. And as we have seen, evolution created many variations of each type.
Why was evolution of the eye highly probable? Because the eye is an emergent complexity that empowers organisms is ways that are consistent with the laws of physics and chemistry. We can say that sight exploits light; the same way that biology exploits carbon’s ability to readily combine with other elements, and with other atoms of carbon itself. Life exploits the chaining ability of carbon. Is any part of evolution inevitable? Yes, it is inevitable that all Earthly life forms must be adapted to the force of Earth’s gravity, to the other three fundamental forces as they are found on Earth, and to the laws of physics and chemistry. (The four fundamental forces are gravity, electromagnetism, and the so-called “strong” and “weak” nuclear forces.)
Principle: Life Tends to Explore —
On Earth, we see that many forms of Life make every effort to explore, experiment, and create. The plant and animal kingdoms find many different ways to see, to hear, to feel, and to smell. Creatures did not just evolve eyes, but ever-more sophisticated and effective eyes according to each species’ environment.
Can we say light “caused” sight? Or that gravity “caused” muscles, bones, tendons and exoskeletons? No, but there is a strong, almost irresistible exploration and adaption of all the forces. That’s why we have evolved our five senses – sight, hearing, touch, taste, and smell. The modern duck-billed platypus and some species of fish also have the ability to generate electric fields and sense the locations of objects that interrupt these fields.
Some animals, including bats and toothed whales, can find objects using sound in a process called echolocation (or “bio-sonar”) which we will talk about shortly.
For those of us on the Path of G>O>D>, there is no intent behind the evolution of the senses, because there was no mind back before the human mind evolved. Although, as we have said several times in this Book, we cannot disprove the existence of an abstract, Deist conception of God who “wound up the system and then set it running, to go wherever it might.”
It would be nice if we humans could see infrared and ultraviolet, or if we had the power of echolocation, but we don’t. But the five senses we do have are wondrously emergent. Wondrously; but not miraculously.
In other words, Life seeks to exploit all the available transmissions and radiations that are not deadly or damaging (like radioactivity). We humans strongly experience this drive to explore, experiment, and create within our own natures. In fact, we use our brains and technology to harness even the radiations that are harmful to us. All of this is why the Path of G>O>D> focuses on these creative, spiritual experiences.
Next, we’ll take the “exploration” of sight and hearing into farther reaches – color vision, “beyond-color” vision, and echo-location hearing.
Color vision evolved fairly early. Color can be essential for perceiving danger and recognizing food sources. Colored flowers and colored vision in insects co-evolved. In a major example of coevolution, researchers have long known that four photopigment opsins (color-sensitive proteins) exist in birds, reptiles, and a number of finned fish. 42 This indicates that about 360 million years ago, the common ancestor of reptiles, amphibians, birds, and mammals had the ability to see colors. 43
Most humans are able to see the colors red, orange, yellow, green, blue, and violet using our three types of retinal “cone cells.” In addition, most of us have brains that can see almost countless mixes and shadings of those colors: red and yellow make orange, blue plus green makes turquoise, and so on. 44
“Dogs only have two types of cones, so they see orange, yellow, and green as yellow. Blue-green is seen as white and red looks as though it is brownish-black. While dogs can see blue, they can’t distinguish shades, especially as the color blue gets darker.” 45 The only animal that has been confirmed to see only in black and white is a fish called the Skate. This is because it has no cone cells in the retina of its eyes. 46
The evolution of trichromatic color vision in primates occurred as the ancestors of modern monkeys, apes, and humans switched from nocturnal activity to diurnal (daytime) activity and began consuming fruits and leaves from flowering plants. 47 Color vision is also present in a number of arthropods—the only terrestrial animals besides the vertebrates to possess this trait. 48
- Process of Adaptation – Biological Adaptation happens when natural selection changes an organism’s structure or behavior in a way that makes it better able to survive and multiply in its environment. In an example from modern technology, electric cars are now being built in response to global concern over the air pollution and global warming produced by gasoline engines.
- Process of Coevolution — Many species of insects and birds have highly-developed color vision. Most evolutionary biologists have concluded that colored flowers and colored vision in insects coevolved. This happened when the insects or birds sought the flowers’ nectar, while the flowering plants sought visits from insects/birds that would then fly to other flowers and fertilize them. This close physical interaction was beneficial to both the flowering plants and insect/bird species. 49 Colored fruits and colored vision in herbivores may also have co-evolved. 50
- Process of Mutualism – Because the close physical interaction between insects/birds and flowering plants was beneficial to both the flowering plant and the insect/bird species, this process is an example of Mutualism, which is one of the types of symbiosis.We can also see examples of processes analogous to mutualism in the technological and cultural worlds. For example, during the centuries of monarchy in Europe, there was a clear symbiosis between Kingship and the Catholic Church. The Church preached that the King or Queen was chosen, blessed, and sanctified by the Church, while the monarch could invoke the power of God to bolster his/her authority and “divine right” to rule. 51 (For more, see our forthcoming Essay, Christianity After Jesus.)
Evolution of Color Vision in Humans
Earth’s first true (“crown”) mammals were small, burrowing creatures who foraged mostly at night. 52 But since the beginning of the Paleogene Period (right after the huge meteor crashed into the Yucatan Peninsula, ending the Age of the Dinosaurs) the small mostly nocturnal mammals that survived grew bigger and became diurnal, moving by adaptive radiation from a burrowing existence and out into the open.
Primates (including the ancestors of humans) were under unusually high evolutionary pressure to discern red and orange fruit from surrounding green leaves in trees and bushes. Fortunately, while most early mammals kept their relatively poor color vision, some primates, including humans, evolved excellent trichromatic color vision, meaning that they have three different color receptors (cone cells) in their retina.
Today, Old World monkeys and apes, including humans, are routinely trichromatic — meaning that both males and females possess three color-proteins called opsins: sensitive to short-wave (red-seeing), medium-wave, and long-wave (violet-seeing) light. 53
However, about 8% of modern human males of northern European descent suffer from red-green color blindness, meaning that they cannot fully distinguish between red and green. Less common is blue-yellow color-blindness. People with these conditions are usually unable to obtain a license to pilot an airplane.
- Process of Adaptive Radiation – The evolution of trichromatic sight in primates is an example of Adaptive Radiation — a process in which organisms diversify rapidly from an ancestral species into a multitude of new forms, particularly when a change in the environment makes new resources available, creates new challenges, or opens new environmental niches. The prototypical example of adaptive radiation is finch speciation on the Galapagos (“Darwin’s finches”), but examples are found worldwide. 55
Birds, turtles, lizards, many fish and some rodents have ultra-violet (UV) receptors in their retinas. These animals can see the UV patterns found on flowers and other wildlife that are invisible to the human eye. Some arthropods can also see ultra-violet light. The UV spectrum falls outside the human visible range, except for some cataract surgery patients. 56
Ultraviolet vision is an especially important adaptation in birds. It allows birds to spot small prey from a distance, navigate, avoid predators, and forage while flying at high speeds. Birds also utilize their broad-spectrum vision to recognize other birds, and in sexual selection. 57
The Transcendence of Color
- Principle: Color is an Emergent Phenomenon. Color vision is an emergent phenomenon for all the creatures (for intelligent creatures, at least) that have that ability.
Take the color red, for example. A spectrometer doesn’t see “red” as a color. It senses colors as wavelengths – the height and frequency of sine curves on its cathode ray tube. The height and frequency of light waves cannot be directly seen by human eyes! No human can tell you the wavelength of the color red without consulting a machine that measures and records those lengths. Instead, the eyes-plus-brains of humans see the waves as “red.” In other words, there is no way you can fully explain “red” to a person who has been blind from birth. You must resort to some analogy – like “The color red is the “hottest” color,” “loudest” color, or the “spiciest” color.
Therefore, the phenomenon of “red” emerges from the entrance of a certain light wavelength into the eyes and brains of certain animals, including humans. The phenomenon of “red” that we see is the product of our complex human-animal perception system in action. Personally, I would rather be able to see red than able to measure its wavelength. For me, the color red is transcendent, while the measure of its wavelength is not.
Somewhat paradoxically, however, an understanding of light wavelengths and wave-frequencies heightens my transcendent appreciation of color. Sensory knowledge and scientific knowledge combine to make a wholistic experience of color that is greater than what the sensory experience or the scientific-knowledge experience can do on their own.
Interestingly, the mantis shrimp sees more colors than any other animal. As compared to humans’ measly three color-receptive cones, the mantis shrimp has 16 color-receptive cones, can detect ten times more colors than a human, and probably sees more colors than any other animal on the planet! They can see in ultraviolet, infrared, and even polarized light. Not only that, but their eyes are on separate stalks and are able to move independently of each other, meaning they’re able to keep an eye watching out for predators and prey in two different directions at once — and in more colors than we can even conceptualize.
Does the mantis shrimp need, or even use all those abilities? That question deserves study, but since those vision capabilities work closely together, creating a synergy, it may be impossible to isolate the contribution of any one ability. (See: “Mantis Shrimp,” article on Wikipedia. See also, http://crosstalk.cell.com/blog/5-things-you-didnt-know-about-how-animals-see-color)
Beyond Our Visible Color Spectrum
Science tells us that Light, whether white or colored, is a form of electromagnetic radiation. We humans see only a very narrow part of the range of that radiation. Beginning at the short-wavelength (and high-frequency) end of the spectrum, the names of the wavelengths are: gamma rays, X-rays, ultraviolet, visible light, infrared, microwaves, and radio waves at the long-wavelength (short frequency) end.
The electromagnetic waves in each of these bands have different characteristics, such as how they are produced, how they interact with matter, and their practical applications. But the shorter the wavelength, the higher the energy.
The visible part of the color spectrum, for humans, runs from near-infrared on the low-frequency end, to near-ultraviolet on the high-frequency end. For great chart of the spectrum, see wiki https://en.wikipedia.org/wiki/Electromagnetic_spectrum.
- Note: All the electromagnetic waves can also be interpreted as streams of massless “particles” called photons, according to the particle-wave duality of modern physics. This “particle-wave duality” is outside the scope of this Essay, but we will address it in our Essay on Modern Physics.
- Note: The term “cosmic ray” is a misnomer due to a historical accident. Cosmic Rays are in fact not a form of electromagnetic radiation. They are actually high-energy particles. As such, they have intrinsic mass.
Pit vipers, pythons, and some boas have infrared-sensitive receptors in deep grooves on the snout, which allow them to “see” the radiated heat of warm-blooded prey. (See https://en.wikipedia.org/wiki/Snake#Perception.)
Near-UV radiation is visible to insects, some mammals, and birds. As we mentioned, many species of small birds have a fourth color receptor for ultraviolet rays, giving these birds “true” UV vision. https://en.wikipedia.org/wiki/Ultraviolet
Over time, humans have discovered and/or invented instruments which can sense and measure all the wavelengths in the spectrum, and machines which can generate them.
- Principle: Intelligence, through technology, can often substitute for shortfalls in our senses.
However, it seems unlikely that we humans could ever experience a dog’s amazing sense of smell, which is roughly 40 times greater than ours. We could one day be able to take and read measurements; but that is not the same as actual smelling what a dog smells. 58
More About Compound Eyes (Found in Insects, Spiders, Crustaceans)
We want to close this section on the Evolution of the Eye with a bit more discussion about Compound Eyes, which are the protuberant, “faceted” eyes found in insects and spiders and other arthropods.
Arthropods are animals with shells (exoskeletons), including insects, spiders, and crustaceans (crabs, lobsters, shrimp, barnacles, etc.). Arthropod eyes are called compound eyes. These eyes are made up of repeating “eye-units,” (ommatidia), each of which functions as a separate visual receptor. 59
Each eye-unit is like a single stalk of corn, with a lens at the top. Each lens makes up a single facet of the eye surface, like a single kernel does on a head of corn. Underneath the lens is a single crystalline cone, and below that is a long shaft lined with pigment cells that ends at the optic nerve. All these light-sensitive eye-units are packed together like the sections of an orange. 60.
The pigment cells in the cone ensure that only light entering the eye-unit parallel (or almost so) to its long axis reaches the visual cells at the base and triggers nerve impulses. Thus, each unit is pointed at just a single area in space and contributes information about only one small area in the field of view.
There may be thousands of units in a compound eye with their facets spread over most of the surface of the eye’s outer hemisphere.
(The photo, courtesy Carolina Biological Supply Company, shows the compound eye of Drosophila melanogaster.)
“The composite of the eye-unit responses is a mosaic image — a pattern of light and dark dots rather like the halftone illustrations in a newspaper or magazine. And just as in those media, the finer the pattern of dots, the better the sharpness (resolution) of the image.” 61
“Grasshopper eyes, with relatively few eye-units, must produce a coarse grainy image. The honeybee and dragonfly have many more ommatidia and a corresponding improvement in their ability to discriminate (“resolve”) detail. Even so, the resolving ability of the honeybee eye is poor in comparison with that of most vertebrate eyes and only 1/60th as good as that of the human eye. So, two objects that we could distinguish between at a distance of 60 feet can only be discriminated by the bee at a distance of one foot.” 62
- Principle of the “Flicker Effect” — The compound eye is excellent at detecting motion. As an object moves across the visual field, units are progressively turned on and off. The resulting “flicker effect” allows insects to respond far better to moving objects than stationary ones. Honeybees, for example, will visit wind-blown flowers more readily than still ones. 63
Story – The Evolution of the Lung
Lungs evolved to breathe in oxygen and breathe out carbon-dioxide. But the very early Earth had an atmosphere containing hardly any oxygen.
Today’s large amount of oxygen (20% of our atmosphere) was produced around 3.5 billion years ago by trillions single-celled cyanobacteria (“blue-green” bacteria) who used photosynthesis to take in carbon dioxide (CO2), “breathe out” free oxygen (O2). They used the energy released by the Process to build their cellular structures.
At first, the exhaled O2 combined with vast amounts of Earth’s surface iron to form iron-oxide (rust). But when the surface iron was all used up, the continuing exhalations put the O2 into the atmosphere. 64
- Process of Natural Selection — We can say Earth’s large percentage of atmospheric oxygen (about 20%) was naturally selected, starting 3.5 billion years ago by the combined atmospheric presence of CO2, a progressive shortage of surface iron, the laws of chemistry, and the metabolism of vast numbers of photosynthesizing cyanobacteria. Without the oxygen exhaled by the early cyanobacteria, all the oxygen-breathing animal life we know today would not have evolved. The entire Oxygen Cycle of Earth today (which we talk about just below) was created by the work of the cyanobacteria.
The Great Oxygenation Event
This revolutionary change, known as The Great Oxygenation Event, took place around 2.4 billion years ago, and it paved the way for all of today’s multicellular animal life, including humans, all of whom breath in O2 and breath out CO2. All these “oxygen-breathing” creatures balance the work of modern green plants, who (like their ancestral cyanobacteria), do photosynthesis and respire (“breathe’) in the opposite way, i.e., CO2 comes in, and O2 goes out.
Cellular respiration is the process in which nutrients are converted into useful energy in a cell. Anaerobic respiration is cellular respiration without oxygen.
It is spectacular to realize that Earliest Life, which was anerobic, was able to evolve countless new species that are aerobic – oxygen breathing – like we humans are. In anaerobes, weakly oxidizing substances such as nitrates and sulfur are used as the final electron acceptors.
But in aerobic organisms, the final electron acceptor is oxygen (essentially, we “burn” our food). Molecular oxygen is a high-energy oxidizing agent and, therefore, is an excellent electron acceptor. This means that more energy is released per oxidized molecule. Therefore, aerobic respiration is more efficient than anerobic. 65
Humans walk and run on two legs, which is more efficient than using four. This ability gives us considerable advantage in hunting, because we can literally pursue our prey to their exhaustion. The fuel for running and walking (as well as for thinking) comes from our food. But to get the energy out of the food we must oxidize it, i.e., “burn” it. 66
In chemistry, burning occurs when substances rapidly combine with oxygen. Burning is a form of oxidation, as is rust, which is far slower. Many carbon compounds burn readily, and when they do, they release energy as heat. Human respiration provides the oxygen that our cells use to burn the carbon molecules (glucose) that the blood transports to them as fuel.
For running, it helps that we have very little body hair, so our sweat can quickly evaporate, cooling the body as we run. Our human bodies are so efficient at oxidizing, cooling, and running that we can run for a longer time, without resting, than any other animals, including horses. 67
However, Evolution does not always find the optimal Use of Energy and Materials. Because sometimes, those optimal patterns cannot be found in a species’ “deck” of genes. Humans are prone to having “back problems” because the backs we use today to carry loads while walking upright originally evolved for animals who walked the Earth on four legs rather than two. Natural selection made a trade-off: by becoming upright two-legged creatures, humans lost their strong backs, but gain the ability to see farther and to walk much farther without tiring.
- Principle: Evolution often makes tradeoffs, and the optimal design is usually not attained.
In addition to the Eye, fundamentalist creationists like to single out the lungs as organs that “would have had no use unless they were created-whole.” However, biologist Richard Dawkins explains that lungs evolved from a proto-lung (“pre-lung”) used by shallow water fish to gulp air and supplement their gills. The fish used an internal chamber of the mouth as a kind of crude lung, and some species enlarged this chamber into a breathing pocket rich in blood vessels. Later, this breathing pocket further evolved into the lungs we see in modern amphibians, reptiles, birds and mammals. (For more on the argument between Fundamentalist Creationists and ourselves (the Evolutionists Who Follow of Continuing Creation), see our Essay, Answering Evolution’s Critics.)
The interior structure of the human lung is amazing. Its bronchial tubes (air-flow tubes) have myriad branchings, getting smaller and smaller as they branch. At the tips of the smallest branches are 300 million tiny sacs (alveolar sacs) and their multiple interior alveoli, which are surrounded by many tiny blood vessels. The sacs hold the incoming air while the alveoli exchange gases between the air and the body’s blood. Basically, oxygen from inhaled air goes into the blood, and carbon-dioxide comes out of the blood and is exhaled. These sacs provide a total surface area of over 70 square yards in each lung. 68
- Process of Exaptation: In a fine example of the process of exaptation, some modern bony fish now use the breathing pocket as a “swim-bladder” which they fill with air to control their buoyancy 69
While the branching structure found in the lungs is truly amazing, it is also very common throughout Nature. Rivers are formed by many small tributaries that feed into them, and then branch out again to form vast deltas as they approach the sea. Tree branches do the same thing – their trunk divides into large branches, then into smaller branches, and then into the twigs that hold the leaves. The interior structure of each leaf is itself a branching pattern. The tree’s root system forms a similar branching pattern. 70 Similarly, in modern economics, goods that are centrally manufactured are often sold and delivered by means of a branching pattern to millions of consumers across an entire country or even world-wide.
Why is the branching pattern so common? Because a branching structure is the most efficient way to gather and deliver flows to many remote points; and to gather flows together from many small points. Engineers have done laboratory experiments that prove this. Their studies have also revealed additional principles that govern when a new branching will most likely occur. 71
- The Process of Branching is the most efficient way to gather flows together into one current, and also to distribute flows outward from a single current to evenly “irrigate” an area or a volume.
These examples of branching are an example of Professor Adrian Bejan’s “Constructal Law:“ Dr. Bejan writes that for a finite-size flow system to persist in time (i.e., to live), its configuration must evolve in such a way that provides easy access to the currents that flow through it. In addition, “everything that moves, whether animate or inanimate, is a flow system.” 72
Interestingly, the taxonomy “tree,” (or “Tree of Life,”) which we described near the front of this Essay, also has a branching pattern, reminding us that Evolution has, over millennia, branched and flowed into as many Earthly ecological niches as it can. However, over those same millions of years, an estimated 99% of all species have gone extinct. 73
- Principle: Evolution has produced many diverse species, and has branched out to fill many ecological niches.
Engineering Designs Govern the Evolution of Living Things
The processes of plants and trees not only follow the laws of physics and chemistry, they also follow engineering principles. Design in Nature, published in 2012 by Professor Adrian Bejan and J. Peder Zane. This groundbreaking book describes how Nature follows engineering designs, including branching, pulley-and-lever, the spiral spring, and hexagons for packing adjacent cells.
- Principle: The Evolution of living systems follows engineering designs.
Upright plants and trees are evolved to take advantage of capillary action and water’s natural tendency to rise from the Earth and evaporate up into the sky (part of the Water Cycle process). Tree trunks and plant stems contain many small tubes which guide water upward from the roots to the leaves. The water passes mineral nutrients to the leaves, aiding photosynthesis, before the leaves release water vapor (and oxygen) into the air. The leaves themselves are distributed and positioned to maximize contact with sunlight, which powers photosynthesis and life itself.
- Principal of Capillary Action — Capillary action is the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces like gravity. If
the diameter of the tube is sufficiently small, then the combination of surface tension (which is caused by cohesion within the liquid) and adhesive forces between the liquid and container wall act to propel the liquid.
- Processes of the Water Cycle — The mass of water on Earth remains fairly constant over time but moves between the major reservoirs of ice, fresh water, saline water, and atmospheric water varies with climate and temperature. The water moves from one reservoir to another, such as from river to ocean, or from the ocean to the atmosphere, by the physical processes of evaporation, condensation, precipitation, infiltration, surface runoff, and subsurface flow. In doing so, the water goes throughdifferent forms: liquid, solid (ice) and vapor.
- Note: The Water Cycle is one of the “Five Cycles of Nature,” or “Ecological Cycles,” or the “Biogeo-chemical Cycles” that work to maintain stability in Earth’s ecosystems. The others are the Carbon Cycle, Phosphorous Cycle, Nitrogen Cycle, and Oxygen Cycle. In addition, geology has the Rock Cycle and the Soil Cycle. These cycles describe how the chemical in the Cycle’s name moves through living things, ecosystems, seas, atmosphere, and soil. Key to these movements are transformation into various chemical compounds for and by the living organisms. All these cycles work to preserve the structure and homeostasis of existing living things, and therefore we do not regard them as evolutionary However, the cycles do provide “platforms” on which evolution can create new organisms and new ecologies.
The honeycombs of bees provide an example of a different engineering principle: Honeycombs viewed in cross-section are hexagons packed together. Since circles enclose the greatest area with the shortest perimeter line, why aren’t they circles? Because when a whole bunch of circles are packed together, there are gaps between all those circles. Place seven pennies together on a tabletop: one interior penny and six surrounding it. You will also see 5 spaces between the center penny and the six surrounding ones. Hexagons, however, can be packed together without any spaces between them. Also, each cell-wall of a hexagon does double duty, because it also serves as the cell-wall of the 6 hexagons surrounding it. For the same reason, the convection cells (Benard cells) in a pot of simmering water are also hexagonal (See our Essay, Complexity and Continuing Creation).
- Principal: Evolution Prefers Constructions that Use Energy and Materials Efficiently. So, evolution tries to follows not only the physics of gravity and electromagnetism; but also engineering principles such as arches, suspension bridges, and hexagonal convection cells. When insects, mammals and other creatures walk on the Earth, they use the engineering principles of columns, levers, cables, and joints that are also employed in mechanical cranes.
The circle and the hexagon are, of course, geometrical structures in mathematics. Nature often exploits engineering principles which flow out of mathematics. Two very common number sequences used again and again throughout the natural world are the sequences that create the spiral (used to construct snail shells, spiral galaxies, and sunflower seeds) and the Zipf’s Law sequence used to govern size distributions seen in geography, botany, and economics. (We talk more extensively about these two mathematical number sequences in our Essay, Mathematics and Continuing Creation.)
- Process of Spiralization, Spirals are created using the Fibonacci Number Sequence — In the Fibonacci Sequence, each number is the sum of the previous two numbers. Here is the sequence:
1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610… and so on.
We see that in this sequence, 8 + 13 = the next Fibonacci number after 13, which is 21. Then, 13 + 21 yields the next number in the Fibonacci sequence, which is 34. And so on. If we draw nested rectangles whose sides are as long as two adjacent numbers, and the connect the corners of the rectangles, we draw a spiral.
- Process of Population Sizing The sizes of individuals in a natural population are often governed by mathematical Power Laws. One of these, Zipf’s Law governs the following population sizing phenomena:
- Most nations have a largest city that’s about twice the size of the second-largest city, and about three times the size of the third-largest city, and so on.
- The largest tree in a forest will often be 2x the size of the next largest tree, 3x the times of the third-largest tree, etc.
Practitioners of Continuing Creation Are “Engineers”
We often say that the Way of G>O>D> is based on Nature, Reason & Science. But Engineering is as important as science for our spiritual path. Today, fundamental physics looks confused to many physicists. Particles are not solid, they seem to be “fuzzy clouds” that can pop in an out of existence. Our universe may be only one of countless multiple universes, and so on. But despite this uncertainty, engineering marches on, relentlessly inventing new substances, new instruments, new designs. The practical work of invention, innovation, and engineering is primary for us because we are all Agents of Continuing Creation before we are “gurus of ultimate understanding.”
The Evolution of Birds: Flight, Feathers, and Beaks
Flying Without Feathers
Today, bats are the only mammals that are able to fly, and they do it without feathers. Bats fly by means of skin stretched from their bodies out to their extended forearms. (Flying squirrels cannot fly, but they are able to glide on the air across short distances.) Both bats and flying squirrels are descended from a long evolution of mammals that did not fly.
Many species of insects also fly, and their evolutionary lineage is very different and distinct from the lineages of both birds and bats. (See Insect Flight in Wikipedia.)
In his book The Blind Watchmaker, Richard Dawkins explains that “Many small animals leap from bough to bough… and the whole body-surface catches the air and assists in the leap, or breaks the fall, by acting as a crude airfoil. Any tendency to increase the ratio of surface area to weight would help, for example flaps of skin growing out in the angles of joints. Bats, the only mammal that can fly, do so using such webs of skin stretched between the joints of its wings.” 74
There were many species of small dinosaurs who were able to fly by means of skin stretched between their bodies and their outstretched forearms. These species include the Dimorphodron, Caudipteryx, and the fairly well-known Pterodactylus.
Some of the flying dinosaurs flew without feathers (in the fashion of bats), some flew with small downy feathers that provided no assistance in flight, and some sported large feathers which may well have aided them in flying. Nearly all the flying dinosaurs had long, sharply-pointed snouts, some of which contained teeth and some which appear to have been beaks.
All modern bird species are descended from some of the smaller species of dinosaur. 75
There is significant evidence that all birds are descended from within the theropod (“beast-footed”) dinosaurs, specifically, within the Maniraptora dinosaur group. 76 Discoveries in northeast China (Liaoning Province) demonstrate that many small theropod dinosaurs did indeed have feathers, most likely for warmth, including the Sinosauropteryx species. (See, https://en.wikipedia.org/wiki/Evolution_of_birds.)
Fossils show that small downy feathers, originally evolved in dinosaurs to preserve body warmth (and/or possibly for display), were inherited by the early birds. Other fossils also show that some dinosaurs had smooth and tapered (“planar”) feathers adapted for flying or gliding, and/or for display to attract a mate. 77
As more non-avian (non-flying) theropods that are closely related to birds are discovered, the distinction between reptiles, dinosaurs, and birds is becoming difficult to discern. 78
Process of Convergent Evolution – Nevertheless, the ability to fly evolved independently at least three times in the history of Evolution. First in the insects, second in the late dinosaurs and early birds; and third in bats, which are mammals. Together, they illustrate the Process of Convergent Evolution: the independent evolution of similar features in two or more species of different periods or epochs in time. Convergence creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups.
In another example of convergent evolution, while sharks and dolphins have very different lineages (the shark is an ancient fish; the dolphin is a recently-evolved mammal) they both evolved torpedo-shaped bodies because this shape allows each of them to swim through water with minimal friction. 79
Convergence shows that the Process of Evolution persistently and repeatedly operates to exploit all the different habitats – sea, land, and air — that Earth provides. Not to mention all the altitudes, temperature ranges, wetness, and dryness of Earth’s varied environments.
Flying Better — with Feathers
The Archaeopteryx, a bird from the Jurassic Period (201 to 145 million years ago), is well-known as one of the first “missing links” to be found in support of bird evolution in the late 19th century. Now generally accepted as transitional between non-avian feathered dinosaurs and modern birds, Archaeopteryx, had had long, smooth, tapered well-adapted for flight. While it may have had the beginning of a beak, it clearly had jaws with sharp teeth and a long bony tail — like dinosaurs and unlike birds.
Evolution may have also tried out mutations in other lines which lengthened and tapered the wing and tail feathers of the first birds. Whenever they did come about, long, smooth feathers proved to be perfect for flight, because they increased the surface area of the wings and tail with almost no gain in body weight. 80.
Process of Exaptation – When a characteristic that evolved for one use becomes adapted for another different use. Feathers originally evolved for warmth among some of the dinosaurs, were later used and adapted by birds to increase their flight speed, maneuverability, and energy conservation. [wiki on Adaptation, p. 84. See image of Sinosauropteryx, a dinosaur with feathers, but no wings.]
Process of Coevolution – The long, well-shaped “flight feathers” of birds coevolved with the evolution of thin, hollow bones that promote flight by decreasing birds’ body weight. Recent studies of bird intelligence show that although their brains are small, they are incredibly packed with neurons, allowing many bird species to be far more intelligent than previously thought ten or twenty years ago. (Excellent modern books on the subject of bird intelligence include The Genius of Birds, by Jennifer Ackerman, 2016; and Bird Brains: The Intelligence of Crows, Ravens, Magpies and Jays by Candace Savage, 2018.)
Process of Creative Competition, or the Evolutionary Arms Race. Birds of prey, especially falcons who can hunt other birds in mid-air, surely evolved their flying in response to the flying ability of the smaller seed-eater birds they hunted; and vice versa. This coevolution created a biological “arms race” for increased airborne speed and maneuverability.
Process of Optimization – Once evolution has opened up a new environmental niche, such as airborne flight, the Process of Optimization often drives the organisms living in this niche to continually evolve body structures that increasingly improve their bodies’ abilities to survive in and exploit the “flying niche.” However, as we’ve discussed, hereditary and environmental circumstances prohibit the evolution of true “optimums.” In pursuit of one feature or ability, we usually have to make sacrifices in others.
Here’s an exchange between Playboy magazine and biologist Richard Dawkins about a similar biological arms race, one between the cheetah and the gazelle:
Playboy: “You’ve had a lot of fun deconstructing the idea of the intelligent designer. You point out that if God made a cheetah fast enough to catch a gazelle and a gazelle fast enough to outrun a cheetah…. “
Dawkins: “Yes. [So then] is God a sadist?”
The Book of G>O>D> handles the paradox this way: “God” didn’t make those creatures, G>O>D> made them. But G>O>D> is not a sadist because G>O>D> is an impersonal Process, not a divine super-person who can be blamed for things. So, the Processes of G>O>D> — the Growing> Organizing> Direction> of the Cosmos — created the falcon, and the smaller bird, and created the acrobatic art of beautiful and amazing flight.
The Process of Creation Through Combination – We can say that the process of Flight was created by the Combination of certain creatures (small dinosaurs, birds, bats) and Earth’s atmosphere. If we think of Earth’s atmosphere (or Earth itself) as a living being, as Gaia, we might call this combination a symbiosis or a cooperation between Gaia and “her birds.”
Principle: Evolution Creates New Processes — Evolution creates not only new creatures, languages, and machines. It also creates new processes (like the process of flight), all acting within the Grand Process of Continuing Creation.
Feathers versus Fur
If feathers work so well for warmth, why are there no mammals with feathers? Why doesn’t a cold-climate creature like the timber wolf have feathers? Because no mammal ancestor ever had feathers. It’s as simple as that. Creatures are not designed, they are evolved. 81
On the other hand, the quest for warmth is a basic drive; temperature is a feature of physics on Earth. So, mammals, who did have ancestors with hair, evolved that hair into thick fur for warmth if they lived in cold climates.
Note: Hair has its origins in the common ancestor of mammals, the synapsids (basically, the pre-mammals) about 300 million years ago. It is currently unknown at what stage the synapsids acquired mammalian characteristics such as body hair and mammary glands, as the fossils only rarely provide direct evidence for soft tissues. However, studies of Russian fossilized feces from the Permian Era suggest that some non-mammalian synapsids had fur. 82
Principle: New Evolutionary Facts lead to New Questions — Virtually every discovery in Evolutionary Biology leads to new questions. Religious Creationists argue “If humans descended from apes, where is the ‘Missing Link,’ the fossil in-between apes and humans”? Today, many “missing links” between monkeys, apes, proto-humans and humans have been discovered. But paleontologists continue to search for more fossils up and down the line, because each one adds a new chapter to the story of human descent. (For more, see our Essay, Answering Evolution’s Critics.)
Story – The Evolution of Beaks
Charles Darwin famously studied the Galapagos finches. He found that the finches on the widely separated islands of the chain had evolved different sized beaks as adaptations to eating the different plant seeds that best grew on each island. Some finch beaks were short and wide, others long and thin. Prevented or discouraged from flying between the islands, the birds evolved into distinct species.
The beak or bill is found mostly in birds, turtles, cephalopods (e.g., squid, cuttlefish, octopus) and in the fossils of some species of dinosaurs. Five species of Australian marsupials, including the duck-billed platypus, also have bills (and they lay eggs). 83
Quite a few smaller dinosaurs had beaks. All modern birds are descended from those dinosaurs; consequently, all modern birds have beaks. 84
The very first thing a small dinosaur or a bird would use its beak for would be to break out of its egg shell. Most beaks work for this purpose because they come to a point (or to an edge) in front of the face. Teeth, on the other hand, typically do not protrude forward from the face. That may be a key reason for the existence of beaks. But a more general reason why evolution has favored beaks is that they have many different uses. A bird beak is used for eating, preening, manipulating objects, killing prey, fighting, probing for food, courtship, and feeding the young.
Beaks and bills are principally made of the protein keratin. Claws, hooves, feathers, hair, and fingernails are also made of keratin. 85 The baleen of baleen-whales consists of long, fibrous strands of keratin. The baleen is located in place of whale teeth is certain whale species. Baleen has the appearance of a huge fringe and is used to sieve the water for plankton and krill. 86 (We should also mention, in passing, that the mouthparts of insects often resemble beaks, but are not made of keratin.)
Fossil evidence shows three dinosaurs with distinctly different lineages lost their teeth after birth and developed beaks. Findings suggest there may be more examples in the fossil record. The fossils one of these species, Limusaurus, lost its teeth as they grew from hatchlings and juveniles to adults. This may have been how the change from toothy dinosaur to beaked bird began. As evolution of these animals progressed, it appears that the transition from teeth to beak happened earlier and earlier in development until it was happening only in the embryo. 87
- Principle of Embryological Parallelism – Embryos often reflect the course of Evolution. For example, the pharyngeal arches in the neck of the human embryo roughly resemble the gill slits of fish (e.g., most sharks), signifying a fish-like ancestor. Pharyngeal arches appear in all tetrapod embryos, including in mammals. Embryo development in the womb does reflect the course of evolution, but that course is far more intricate and quirky than biologists envisioned in the late 1800s. 88
The Advantages of Beaks over Teeth
Of course, no one knows why many of the small dinosaurs evolved beaks and abandoned their teeth, but beaks seem to offer these advantages: Beaks protrude from the face, allowing the creature to attack “weapon-first.” The beak’s fine point permits its owner to precisely pick up a small prey and kill it in the same grasp, without concern that the prey might twist around and bite or sting its lips. Beaks are better-suited to de-shelling nuts and seeds than teeth are.
Beaks are also lighter in weight than jawbones-plus-teeth, helping creatures evolve toward flight. Beaks are self-renewing (growing from the base), and self-sharpening. Perhaps most important, beaks grow more quickly and with a smaller energy requirement than do the growths of jawbones and teeth. This reduces the time a “chick” must spend in the egg where it is vulnerable to egg-eating predators. 89
Birds Are Not the Only Modern Creatures with Beaks.
As we mentioned, Cephalopods (e.g., octopus, squid, cuttlefish) all have beaks, located at the inner center of their tentacles. The tentacles grab these creatures’ prey and pull it inwards toward the beak, which kills and eats the prey.
Billfish (including sailfish, swordfish, and marlin) have very long, sword-like beaks. Adult swordfish have no teeth, and other billfish have only small file-like teeth. (Note: although pufferfish appear to have beaks, they do not. They have beak-like teeth that are fused together.)
The Australian Platypus Has a Beak
The modern Australian platypus, has a prominent, duck-like bill.
Fossilized skeletons of two platypus-like animals – Teinolophos and Steropodon — have been discovered in Australia. They date back to 123 million and 105 million years ago, respectively. The older Teinolophos had teeth, and no beak. The more recent Steropodon shows a fossilized lower jawbone with three molar teeth and a beak. The modern platypus has a beak and no teeth. Together, the chronology of the three animals indicates a progression from teeth to beak. (Although the two prehistoric animals may not have been direct ancestors of the modern platypus, they were very similar in appearance to today’s platypus. 90
Like other monotremes, the platypus can sense objects through “electrolocation.”
Process of Electrolocation — The Australian platypus can locate objects in the deepest and darkest of waters by using electro-receptors located on its bill. Electrolocation is a mode of animal perception through the sensing of electric fields. Some animals can generate relatively weak electric fields that can be used for detecting objects and communicating with other members of a species.
Still other species, such as the electric eel, generate electric fields strong enough to shock other animals. These shocks can be both defensive and offensive — they can ward off predators and/or stun animals that are to be killed and eaten. Most of the species that have this ability are fish, because electric fields work better in water than in air. 91
Note: It is interesting to note that the platypus is also one of the few species of venomous mammals, because the male platypus has a spur on the hind foot that delivers a venom capable of causing severe pain to humans.
Feathers, Flowers, and The Evolution of Beauty
We’ve said that the early feathers of some smaller dinosaurs evolved for insulation; but they also may have evolved for display, i.e. to attract a mate. The flight feathers of birds then evolved from the much earlier feathers the dinosaurs used for insulation and/or for display. 92
In addition to their “warmth feathers,” most modern birds evolved sculpted, tapered feathers that augment their ability to fly with speed, control, and grace. 93
In many bird species, these feathers have also evolved beautiful, vibrant (even iridescent) colors as a way to attract mates. Most often, it is the male of the species who sports the strong colors (and often sings a distinct song and/or does a weaving, bobbing dance) to attract the plainer female of the species to mate with him.
The Peacock and the Peahen
Perhaps the most extreme male plumage is borne by the peacock (the male of the peafowl species), who sports a gigantic set of tailfeathers, each as much as four feet long, which the
male fans out in a great semi-circle for display to the female peahens.
These peacock feathers are cumbersome in fighting, they require great deal of energy to grow and maintain, they reduce the peacock’s maneuverability and flight, and make him hugely conspicuous to predators. 94
Studies show that the tail does lower the overall fitness of the individuals who possess it. Yet, the grand plumage has evolved, indicating that peacocks with longer and more colorfully elaborate tails have some sexual-selection advantage over peacocks who don’t. The peacock’s ornamental train (grown anew in time for each mating season) is a famous “adaptation” that borders on maladaptation, i.e. on being “more trouble than its worth.” 95
Most biologists think that the females associate the bright-and-big plumage with male survivability — strength, longevity, food-finding ability, flying ability, and fecundity. But other biologists question whether this is logical. In any case, if the females think bright plumage indicates survivability, and they do favor males that have it, then those males will breed more and produce more chicks (especially more bright-plumed male chicks) than the dull-colored males will produce.
Thus, the bright males mate more often, thus breeding more bright males, and so on in a steady positive feedback loop that creates and preserves bright male plumage down through the generations.
Note: At the time of this writing, May, 2020, Biologists have opposing theories about a relationship between sexual selection and a tendency toward beauty. For a deeper discussion, see Wikipedia’s article on Sexual Selection — https://en.wikipedia.org/wiki/Sexual_selection
Processes of Positive Feedback and Self-fulfilling Prophesy – These examples of bright-and-big bird plumage demonstrate a positive feedback loop in the arena of biological systems. This process can also be called a “self-fulfilling prophesy” in culture; or “gaining momentum” in business (“nothing succeeds like success”), team sports or warfare; “becoming a craze” in the world of fashion; or “going viral” in the realm of computerized cultural memes.
The Bull Elk’s Antlers
Color and courtship display are also found in other types of animals, including insects, lizards and mammals. For example, consider the huge antlers of male North American elk. These antlers are made of bone. They can grow four inches a day, reaching as much as 6 feet across and coming to 12 or more sharp points.
Yes, the antlers are used to defend the herd of female elk against a pack of wolves, but their tremendous size also requires a lot of nutrition (a fresh “rack” of antlers grows anew each year) and they can entangle bull elk in the trees, leaving him (and his herd) quite vulnerable to attack. The antlers are most used to engage in ritual combat – tests of strength with other bull elks, and the losers usually retreat without being killed. (See the Wikipedia article for Elk, https://en.wikipedia.org/wiki/Elk.)
Yet the cow elks of the elk herds continue to choose the well-racked bull over “less-horny” males. Does size ever tip the scales and become counter-productive? Most likely the size of many racks is perched right on the verge of decreasing usefulness.
- Principle: The Law of Diminishing Returns – This law works in biological evolution as it does in technology and economics. As peacocks elaborate their tail-feathers, and as bull elks elaborate their antlers, each round of evolved elaboration adds less and less to the survivability of the herd.
We can also clearly see a wide difference between the appearances of the male and female in many, many species; especially animal species, such as the peafowl and the elk. The
term for this is “sexual dimorphism.”
- Process of Sexual Dimorphism – “Sexual dimorphism is the condition where the two sexes of the same species exhibit different characteristics beyond the differences in their sexual organs. The condition occurs in many animals and some plants. Differences may include size, weight, color, markings, and may also include behavioral and cognitive differences. These differences may be subtle or exaggerated, and may result from sexual selection and/or natural selection.”
Process of Runaway Selection (a.k.a., “Fisherian Runaway”)
This brings us to the Process or Theory of Runaway Selection.
The Process of Runaway Selection — Says that the positive feedback loops we described for male peacock feathers and elk antlers often do get out of control in the animal kingdom. It happens often enough to constitute the Process of Runaway Selection.
A. First, In the 1930’s, statistician R.A. Fisher argued that initially, size and ornamentation signaled greater potential fitness (the likelihood of leaving more descendants), so preference for the ornament had a selective advantage early on. Subsequently, the female’s preference for ornamentation in mate selection, if it was strong enough, could outweigh a male’s decreased fighting ability, i.e., when the big fancy peacock tail had become non-adaptive. 96 Over subsequent generations this can lead to “runaway selection,” which is now also called “Fisherian Runaway.”
B. Secondly, Fisher drew an important distinction between individual fitness and group fitness, as follows: Although the relative reproductive fitness of individual peacock males with large tails remains higher than those without tails, the absolute fitness levels of all the members of the population (both male and female) is less than it would be if none of the peahens (or only a small number) had a preference for enormous exaggerated tailfeathers on males. 97
C. Thirdly, while the increasing size of peacock tails might stop or be reversed because of their cumbersomeness, there could be nothing that turns back an elaboration of color and pattern, neither of which add any weight. If so, then the “runaways” of color and pattern would constitute a clear pursuit of beauty for its own sake within the Processes of Evolution. Then this self-organizing, coevolutionary process would then be a standard of beauty that stands by itself, without providing any adaptive benefit for survival. Even Darwin, writing in 1871, thought that this phenomenon was so widespread in Nature that it likely constitutes a preference for beauty in evolution.
Is There a “Preference” for Beauty in Evolution?
In 2017, ornithologist and evolutionary biologist Richard O. Prum published his book, The Evolution of Beauty: How Darwin’s Forgotten Theory of Mate Choice Shapes the Animal World —and Us, (2017, Doubleday). Dr. Prum writes about the power of aesthetic mate-choice and argues that it is an important independent agent in evolution.
Prum indicates that while Charles Darwin made this argument in The Descent of Man, published in 1871, the concept was sidelined and forgotten. A consensus developed that the sole driver of evolution is natural selection based on survivability through time of reproduction, not “beauty.” 98
Dr. Prum describes many examples in avian evolution where aesthetics seems to be preeminent. However, peer review of Dr. Prum’s book indicates that most of the scientific community found logical fault with the book’s arguments. The critics maintained the consensus view that only “survivability-to-time-of-reproduction” counts in natural selection. There is no “aesthetic sense” inside Evolution that sustains beauty as an end in itself. 99
The Book of G>O>D> notes that the minds of living things (including the minds of peahens and cow-elk) have never been completely “rational.” Their preferences can start out being rational, and then they can get carried away – a kind of addiction to beauty, if you will.
The Way of G>O>D> also points out that most human beings very much appreciate the beauty of the natural world – galaxies, crystals, flowers, birds, and bird songs are prime examples. We also see and hear beauty in culture and technology. In fact, we pursue beauty in culture and technology. Since we are creatures of evolution, and also agents of evolution, does this not indicate a tendency toward beauty in Evolution itself?
In human hands, Evolution becomes Guided Evolution. With human agency at the helm, Evolution can speed up; it can have higher information content; and lower energy and material content. Guided Evolution can also be aimed at achieving goals that are important for humans, important for other living things, and important for Mother Earth. One of these goals appears to be the creation of beauty.
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