In the previous entry, we looked into the question of what is evolution, from the standpoint of The Origin of Species, by Charles Darwin. We saw that several components needed to come together in order for Darwin to formulate a naturalist account, for the diversity we see in the biosphere.
In the first treatment, we covered the role of human breeders acting to select and breed certain animals, to amplify traits that were most beneficial for humans. We learned that the practice of domesticating animals and plants for human purposes, was something of a testbed and a living laboratory for Darwin. He used them to observe the power of human selection, to influence traits through successive generations of animals and plants.
We saw that once Darwin recognized the power of human selection to change animals such as dogs, into all manner of distinct forms, he had to deal with the issue of variation, and from where it springs. Even though it was held by many contemporaries of Darwin, that variation was somehow specific to animals bred by humans, Darwin saw past this. He realized that humans only had the most blunt and imprecise control over selecting traits through breeding. The variation that created certain traits, in the first place, was never something being controlled directly by humans. The takeaway is that variation among successive generations, was always an uncontrollably wild aspect of nature, and thus Darwin knew it would also occur well beyond the confines of human intervention.
In this entry, we will examine these twin pillars, of selection and variation. Human directed selection that could dramatically influence traits over time, and the wild nature of variation between generations. These concepts set the foundation for Darwin to make the final leap needed, for a naturalist account of the origin of species. This most crucial jump, was the idea that plants and animals could evolve into different species, without the intelligent design of a god, or the profit minded selection of human breeders. Darwin’s insight was that nature could create the diversity of the biosphere, through a process of natural selection alone.
Evolution by Natural Selection
It is a peculiar curse of knowledge, that once something becomes known, it is quite nearly impossible to imagine the prior state of ignorance. This is something that those of us who look into the development of human understanding, constantly have to wrestle with.
The problem with any account of Darwin’s theory of evolution by natural selection, is that we generally encounter it from a position of long-established fact, rather than from one of curiosity and wonder. In order to break out of that stale trap, there is an attempt in these entries on Darwin’s theory, to actually do a little bit of work, not frequently seen in modern accounts of evolution. The aim is to follow some of the questions and conclusions, that lead to the theory, rather than to just deliver it all at once, and to rob it of some gravity and proper impact in so doing.
With that in mind, we now turn to the crux of the matter, and investigate the issue of selection.
With the combination of human selection, and natural variation, Darwin had a model that he could apply to the greater biosphere. Now he only had to replace the breeders acting for their own gain, with natural processes in the wild.
From Human Selectors to Nature Itself
By the year 1859, Darwin was confident that he had indeed hit upon the true secret of nature’s workmanship, regarding the origin of species. It was in this year that he published his storied manuscript, that essentially created the field of evolutionary biology.
He knew that if humans could take any number of animals and plants from the wild, and find uses for specific traits, then so could nature. He thought that if humans could figure out how to amplify those most useful traits through selective breeding, that nature should effectively be able to do the same.
Let it also be borne in mind how infinitely complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life; and consequently what infinitely varied diversities of structure might be of use to each being under changing conditions of life. Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should occur in the course of many successive generations? ― Charles Darwin, The Origin of Species
There were several issues that made this conceptual leap from human directed selection to natural selection, more difficult to conceive of. For one, you had to get past the singular act of a human deciding to breed certain animals to preserve and amplify beneficial traits. Instead, you had to imagine that the “selection” could effectively be accomplished through an aggregate of small interactions and processes, that were almost all undirected, in the sense of lacking any top down “selector”1.
Objections to the Phrase “Natural Selection”
One of the problems Darwin faced, was the objection to his use of the phrase “Natural Selection”. It appears that many people did not know how literally to take his words, and I actually suspect there are still remnants of this issue to this day.
Several writers have misapprehended or objected to the term Natural Selection. Some have even imagined that natural selection induces variability, whereas it implies only the preservation of such variations as arise and are beneficial to the being under its conditions of life. ― Charles Darwin, The Origin of Species
It is important to understand that the term “Natural Selection” is not to be taken as a total description of the process of evolution. That is not to imply that it is not relevant or meaningful, but just that I think we make more of the term than Darwin did himself. The key that I think we miss, particularly until we immerse ourselves in the context of Darwin’s intellectual journey, is that aspect where the first step is to understand “Human Selection” among domesticated animals.
Darwin was essentially nailing down the first version of his model, as “Human Selection + Natural Variation”. So, the next step was to take “Natural Variation” but to replace “Human Selection” with “Natural Selection” in the wild.
When viewed from this historical perspective that takes the development of Darwin’s own thinking into account, the term “Natural Selection” has a bit of a different flavor to it, than seeing it out of context. It becomes less about nature doing something with human like aims and intelligence, and more about replacing human direction, with natural mechanisms.
The Slippery Slope from “Selection” to “Intention”
Another problem that Darwin had to surmount, was the misunderstanding, caused by the slippery nature of the word “selection” specifically. This word alone, I think, has caused much more confusion and controversy about Darwin’s work, and perhaps the whole field of evolutionary biology, than perhaps anything else besides blatant religiosity. I am sure there were a fair share of bad actors in the past, as well as those in the present, who deliberately misrepresent Darwin’s work. That said, I also recognize, that even for myself, the word “selection” is a bit problematic when taken at face value.
Here, in Darwin’s own words, he describes his acknowledgment of the issue with the word “selection”.
Others have objected that the term selection implies conscious choice in the animals which become modified; and it has even been urged that, as plants have no volition, natural selection is not applicable to them! ― Charles Darwin, The Origin of Species
The problem I believe Darwin ran into, with the word “selection” is that it is very hard for many people to imagine a “selection”, without an intentional, and perhaps even intelligent “selector”.
The philosopher, Danial Dennett, has a concept he describes as “Competence without Comprehension”, that is important for understanding the essence of Darwin’s theory. Dennett uses this concept to describe the mindless processes in computers, and the blind mechanisms and instincts of the natural world. The takeaway, is that both in computers and in nature, we observe outputs that appear to be signs of high competence, and yet we have no locus of comprehension to explain such competence. I think this concept is very much at the heart of what made Darwin’s theory of evolution, by natural selection, so difficult for many to accept. At first glance, it just doesn’t seem that a high degree of competence, without comprehension, should be possible. This is largely because of a human perspective wherein, high degrees of competence are often correlated with high measures of comprehension for the relevant area of activity. For example, we do not become competent at riding a bike, until we have the experience and comprehension, of how forward motion allows us to balance on two wheels. On the flip side, organs such as the liver in our bodies, are constantly performing all manner of insanely complex chemical processes, and yet we have no anthropomorphic locus of comprehension, from where such fantastic competence could be generated.
There is much more that will be said regarding this kind of seemingly mysterious paradox, in other entries in this series and beyond. This issue of “Competence without Comprehension” and the notion of procedural/computational thinking, are far more foundational than you might think. They are essential to understanding the universe and the human experience, beyond evolution in the biosphere alone.
For now, I would like to suggest a way to think about natural “selection”, that may remedy this difficulty to at least some degree, for conceiving of how nature can demonstrate competence without comprehension. The basic idea is to invert the concept of selection, from being an intentional decision, to being more like a fire. By this, I mean to think of it as “Natural Elimination” or “Natural Reduction” instead of “Natural Selection”. The point being, that although we can have difficulty imagining “selection” without an intelligent “selector”, we can much more readily accept the concept of nature eliminating animals and forms from the world. It is common to see systems of all kinds, wearing down and breaking. We see animals and people dying all the time. We do not find it at all mysterious that forest fires can burn through miles of trees, even though the emergence of trees from the ground, can seem almost magical in comparison.
So, the fact that nature can eliminate forms from the world, may seem much more “natural” than the idea that nature can “select” forms unknowingly, in a way that, nevertheless, appears intelligent. I don’t want to go deeper into this topic here, as there will be an appropriate time for the richer conversation later on. I just wanted to briefly make this inverted view available, in case it helps you to better understand what is really meant by “Natural Selection” in evolution, as it applies to nature overall.
In this entry, we looked at the concept of “Natural Selection”, and some of the problems Darwin’s theory had to face. Difficulties of how to conceive of a selection process, with no intelligent or intentional selector.
Many of these difficulties, which existed at the inception of Darwin’s theory, remain thorns in our side, even up to the present day. That said, the basic genius and rigor of the theory, shines through the clouds of confusion and rejection, like a lighthouse on a foggy night. Even if you cannot resolve each detail of the bricks and windows of the lighthouse, the beacon will guide you in the right direction, if you follow it. This is how the legacy of Darwin’s “The Origin of Species” should be judged and remembered. Not for the perfect placement of every little brick in its edifice, but for the brilliance of the beam. A light that continues to lead us onward, to understand nature’s wonder’s on her terms, and not to burden them with the baggage of human narratives.
Looking forward, in future entries of the series “Survival, Success, and Significance”, we will move on from “The Origin of Species”, and get a sense for its pivotal role, in shaping the “modern synthesis” of evolutionary biology. A view that will take us from the largest scales of evolution, to the smallest scales of genes and cells. All of which, ultimately, helps us to better understand the origin and trajectory of our own human experience.
- The “almost” is used here, as a qualifier to acknowledge that the actual animals themselves, must have some degree of agency in for example, selecting mates etc. That said, when one looks to the world of plants, where the concept of agency seems difficult if not impossible to discern, you recover an even cleaner sense of an utterly undirected process of natural selection. ↩︎