So I’ve been reading Richard Dawkin’s “The Greatest Show on Earth”, interestingly for a guy who is constantly described as condescending and downright mean his book thus far has been really well thought out and pleasant. He’s barely mentioned faith at all and seemed to make an effort to separate faithful from “those people” (Creationists/Young Earthers). He seems genuinely concerned with people trying to discount Physics and about a half dozen other sciences as being “other forms of faith”. But I digress, that is not what this post is about :).
In the book Dawkin’s mentions something about rats, how through selective breeding in a matter of 30 or so generations (or even quite a bit less) you can generate rats who have far better dental than those not selected specifically to enhance those traits. Likewise you can make rats who get really crappy teeth fairly quickly. He mentions in this chapter, “Why if man can make a rat with awesome teeth can nature not? One would assume that long surviving healthy teeth would do nothing but enhance the survival rates of the hose animal.” Which was interestingly timed because I was thinking the same thing.
I had been wondering about all the monsters that folks create for movies, these apex predators with amazing senses, huge muscular structures, good bones, and many cases wings because obviously flying is badass. One would assume that these creatures should be inevitable in life, likewise the question arises even on a smaller scale, why if Human’s have gotten these fairly awesome brains have other animals not jumped on the bandwagon? They are sexy organic computers that have helped us to create super cool things. One would think that any animal would benefit, much like the rats from the fancy teeth.
To this question, that he assumed (rightly) would form from the discussion of that rat experiment, he responded with an Economics quote that I’ll paraphrase “There is no such thing as a free lunch.” The Calcium necessary for those teeth must come from somewhere, in lab rats it is simply supplemented with a seemingly endless supply of nutrient rich food. But in the wild the Rat would have to get that calcium from somewhere. It would be taking it away from the rest of it’s bone structure, or in females from the milk production, or any other process in the body that needs that Calcium. In the end, having slightly worse teeth for the wild rats might be beneficial because the calcium they’d have used in those teeth can then be used for other operations in the body that may actually extend their life even further.
Which brings me back to the human brain thing. I’ve read, long before this book, about the reason why humans are so gung-ho on fat and high calorie diets. Obviously being warm blooded is a big part of it, but beyond being walking waste machines (we do burn through energy really fast), we also have incredibly nutrient hungry brains. These big grey batches of yogurt are very big on the high fat high calorie diets that we take in, it makes them happier than a clam (both of which I don’t think actually feel happy, but you get my point). At a point in the history of our particular branch of the animal Kingdom there was a period of very high fertility in the land where our ancestors lived. This provided them with the resources they needed for a mutation of the brain to actually work, before that point HAD the event occurred the animal carrying that new brain would have not had the food supply to support the new infrastructure and would have likely died off.
It’s hardly a give-in, by stuffing animals full of vitamins and minerals for centuries we have no certainty that they’d suddenly get awesome brains and be able to help us fight the inevitable ape uprising. However it makes me wonder how many times in the past a really neat strain of an animal has arisen and died off because it couldn’t support the new workings of its body. Requiring perhaps more vitamin C than was available, or Vitamin D, or Calcium, or Iron. The only thing killing off it’s otherwise (subjectively) superior body was the environment not supplying it with the funds (so to speak) it needed to succeed.
We, long ago, hit a point where we begin a cyclical system of altering our environment to meet the ever (however slowly) changing needs of our bodies. We’ve reached the point now that any mutation we have can likely be met with environmental changes to help support it, providing us with an infinitely many versions of humans that can survive…at least hypothetically.
It’s an amazing moment personally, wondering just what has been lost or what could be gained in the animal kingdom given a sustained period of fruitfulness, however I find that the odds of this happening with humans around is quite a bit lower than it once was (we’ll utterly consume any place that begins to thrive). At any rate, it’s a neat bit of info. If anyone was ever wondering why animals don’t get X, the above is the basic reasoning. Every mutation requires resources and if those resources are taken away from even (for the moment) more important bodily functions that mutation will fail. It is only the mutations that result in a slightly longer lifespan (and thusly more chances to breed) that lead onto new strains of the animal, and those strains will only survive for as long as their needs are met by the environment. They could still vanish if the environment suddenly changes and their “inferior” cousins could end up returning to power.
Bah…I’ll end up bantering on about how neat this is to me. So I’ll just leave it at that. More to come I’m sure.