Evolution as Fact

(Picture from here.)

Mostly I think evolution speaks for itself.

But I’d be remiss if I didn’t talk at least a little about people’s difficulty with it. Consequently, this is mostly an opinion piece rather than a discussion of science.

Personally, I think evolution has sufficiently proved itself to move from the scientific concept of theory to the scientific concept of fact. No scientist of any integrity disputes the fact that we got here by a natural mechanism that we call evolution. The component parts of the mechanism are in dispute, argument and enthusiastic debate. But no one disputes that evolution happened.

It’s the same way the no one disputes the facts explained by Maxwell’s Equations or Newton’s Laws of Motion. Maxwell’s equations explain the phenomenon he observed regarding electricity and Newton’s equations explain the operation of the phenomenon of motion. That neither model is complete does not refute the fact that there is electricity or the fact there is motion.

Natural selection is the model. Evolution is the fact.

But unlike electricity and motion, evolution strikes at the heart of human exceptionalism. Human exceptionalism is the belief that we are special beyond our natural endowments. It usually takes the form that humans are endowed of their abilities by God.

This should not be surprising.

A species by its definition must distinguish between like and not like, otherwise propagation is impossible. Arising from that, reproductive groups distinguish between mine and not mine– horses, cows, lions and gorillas all make that distinction. Chimpanzees make war against other bands, showing that they have made the leap from reproductive group to societal abstraction. From mine to my people.

One of the human abilities we so prize is the ability to abstract– the ability to simplify and categorize like things together. The ironclad concept of species itself is a human invention. Reproductive isolation in the wild is much more complex and interesting. (What’s the nature of the species boundary between dog and wolf, for example?)

Abstraction is an enormously powerful tool. From it we have deduced cosmology, Euclidean geometry and evolution.

We apply this ability to ourselves and derive nations, states, political ideology and religion which, I submit, are all examples of human exceptionalism. Democrats are better than Republicans. Americans are better than Canadians. Southerners are better than Yankees. Christians are better than Moslems. On and on and on.

I wonder sometimes if we would benefit as a species if we would just stop thinking about ourselves all the time. We’re a tiny piece of life on the world that through bizarre happenstance developed abilities that give us inordinate power.

We’ve been to the moon, cracked the atom and moved machinery with only the circuits of our brain. We’ve also not managed to make it back in thirty years, burn the atom like it was coal and are figuring out how to better manipulate our brain to make us buy more things from China.

Our view of our exceptional selves was advantageous for the last several thousand years. (For a fun view of this, see Milo Manara’s Man. NSFW.) But at some point in the recent past we reached a tipping point, a point beyond which considering ourselves as the sole important group on the planet, made things worse instead of better. I’m not sure when it began but it is unmistakably true now.

The philosophical worth of human beings has been paramount throughout our history. The corollary of that is the worth of human effort has been valued over the natural world. James Watt said in an interview I heard years ago that it wasn’t that he didn’t value wildlife; it was that he valued human beings more. By extension, he valued human property as symbolic of human worth since he had no trouble developing public land for private interest. Humans, as exceptional creatures, have decided they have the moral right to exploit the living world as they see fit.

I think it’s time to change that outlook. And I think it begins by not thinking of ourselves as a special creation outside the operations of nature but as something that evolved directly by the operations of nature.

I don’t mean that we are part of everything in the world in some subjective spiritual way. I mean it in an objective mechanism. As Tom Lehrer sang in Pollution:

The breakfast garbage that you throw in to the bay,
They drink at lunch in san jose.

Or perhaps we should quote Benjamin Franklin:

We must all hang together, or assuredly we shall all hang separately.




Evolution as Fact — 8 Comments

  1. Interesting that those who deny evolution accept quite readily the forced evolution of selective breeding of livestock to produce a sheep with more meat, a cow with more milk, a chicken that lays eggs every day but won’t brood, heartier wheat, disease resistant tomatoes etc.

    Evolution is a fact of life in the farm yard.

  2. Ah, but Phyllis, artificial selection is different, because it’s an expression of human dominance. Plenty of people have believed, for example, in eugenic policies but denied evolution–notably Hitler.

  3. I enjoyed your post on Heroism and Miles (linked from Lois’s blog), so I wandered around and saw this post.

    I’ve been curious for a while about this. Although we can look around and pretty easily see (through both nature and man-guided breeding over generations of dogs or horses or whatnot) that creatures can be bred for specific traits…. What do you feel are the solid foundations of evolution as the origin of the species?

    Although I haven’t been a particularly avid researcher of either side of the issue, I’ve NOT been impressed with the evidence I’ve seen related to an explanation for how “everything” “got here” in the first place, and specifically how complex organisms — especially intelligent, self-aware organisms — could possibly happen “by accident”.

    It bugs me whenever evolution-as-origin is presented as “fact” because even scientifically speaking I have not seen any significant evidence to that end.

    Enlighten me, please? Specific books or papers would be helpful…

  4. A “species” has at its heart effective reproductive isolation such that selection can act upon a group without being compromised by outside genetic input. There was a frog I learned about in college (whose species name I do not recall) that lived in two locations, at the canyon rim of the site and in the canyon valley. The two animals appeared to be physically identical. However, upon close examination the they did not appear to interbreed. Even in the laboratory. Investigation revealed that one of the groups (I forget which) was making its call at twice the rate of the other. This effectively reproductively isolated it. Subsequent investigation showed that the “quick” frog group had undergone chromosome doubling– rare in vertebrates but it does happen. Consequently, it was now reproductively isolated from the parent group. The discussion at that time was whether this was a new species or a sub-species, since it appeared to be physically identical. I would argue that the intransigent nature of the reproductive isolation (it’s pretty unheard of to un-double a chromosome) made it a species. Regardless, now the new group could be selected against without the effect being diluted by influence from the parent group.

    There’s an interesting faq about speciation here:

    The NSF also has a good evolution section and here are some articles about it:

  5. Addendum:

    Just some small additional points: evolution is the model for how organisms changed over time from the point at which natural selection could occur– once life began, for example. No one has a good model of how life began and until that occurs no one can say what role natural selection played. The natural selection model applies extremely well– to the point of “scientific theory”– once life occurred.

    Second, no reputable scientist will ever say that a given organism got here “by accident”. Evolution is not an accident. Evolution results from circumstances presenting an opportunity for the natural variability of organisms to make a difference in reproduction. If there is an advantage to being fast in the animal’s circumstances that animal is going to breed more effectively and pass on that trait to its offspring. There is *nothing* accidental about that.

    There is chance and circumstance at two ends of the selection process. The variability present in animal populations is one arena where changes that have a random character to them occur. Even this over time can have less randomness than one might first think. Cuttlefish, for example, have a variability within their reproductive strategy. One subgroup has a battle for dominance approach to win over a female. Another sneaks in and makes itself look like a female until it can present itself for mating. *Both* strategies occur in the same population. That sort of variability has been preserved.

    The other area that is more truly random is the nature of the surrounding circumstances– the ecology and physical surroundings of the organism. But here, too, animals can adapt to each other as well as to the physical environment, thereby altering odds in their favor.

    But the randomness of the physical geography over time also has an influence. One of my professors said that you only really know an organism if you can observe it over a few tens of thousands of years. Because the organism that is presented to you isn’t just the organism that succeeded in the environment you’re observing it in, it’s the organism that survived all of the droughts, rains, ice ages and meteor strikes prior to the environment you’re observing it in.

    Finally, I think the crux of the problem isn’t other animals; it’s our own evolution that matters to us. The descent of man is pretty well worked out now in that the basic sequence of species is known. What we don’t know (at least I don’t think we know. Others probably know more) are the selective pressures that caused the changes.

    And then *Something Happened* about fifty-to-eighty thousand years ago that put us on the trail to where we are now. We don’t know what that was. Whatever it was it hasn’t seemed fossilize.

    But that species fifty thousand years ago did become us. Not through any set of random events but by winnowing out those who *weren’t* us and mating with those who became us. Again, the selective pressures are obscure though there is some interesting work coming out of South Africa suggesting we started eating fish.

    For reasons that are difficult for me to understand it is hard for a lot of people to accept “Man still bears in his bodily frame the indelible stamp of his lowly origin.” We are tremendous beings. And that magnificent heritage is the result of thousands of decisions of people over thousands of years. How could we possibly expect those decisions not to help form who we are? And if those decisions are pushed back far enough how could we not expect those that made them would not be human?

    Personally, I find this a wonderful idea. It says, concretely, we came from somewhere through the actions of those much like ourselves. It says we’re going somewhere; that our actions and decisions bear long term consequences not in some hereafter but here, now, and in the future. It gives heft and meaning to what we do right now in the physical world around us. We are responsible for what we do and what we do matters. As did the actions of Ogg, fifty thousand years ago, sitting out in front of a cave in South Africa, watching the fish jump and wondering if they were good to eat.

  6. Evolution is a fact. You can see it happening every day in biology labs, farms and hospitals (heard of antibiotic-resistant bacteria)? I find it astonishing — and terribly discouraging — that in this century, in this country, it’s still even remotely a subject of contention.

    A good starting point: Jerry Coyne’s Why Evolution is True.

  7. Steve–thank you, not only for the initial post, but for your thoughtful follow-ups. I’m not sure I’ve ever heard my own feelings on evolution put so clearly or elegantly. I too find this a “wonderful idea” and one with an inherent moral energy: We are responsible for what we do, and what we do matters.