This past summer, I spent a morning at the St. Louis Zoo with my daughter. We were having a lovely morning, walking up toward the area of the Zoo set aside for the “Big Cats,” when we came across a peacock in full strut mode, his beautiful plumage on display for all to see. A little later we came across him again, still showing off, wandering down a narrow path where his impressive spread made getting past him a little difficult. It was beautiful to see.
Since that morning, I’ve been thinking a lot about that peacock and Darwin’s theory of the survival of the fittest. I want to share some of those thoughts here, but I figure I should show my hand up front – while I’m definitely in the intelligent design camp, I get frustrated with how a lot of Christians discuss the theory of evolution. Consequently, I’m going to spend some time in a future post explaining my basic thoughts on the matter. For now, though, I want to express in a less systematic way my musings on what a peacock might tell us about the nature of the universe.
OK, so we all know that natural selection is the idea that adaptations which increase the survival value of a species are more likely to be passed along, as the animals that have them are more likely to survive & reproduce, thus tending over time to change the nature of a specific animal species’ population. At face value, that concept is at least logical, whether or not one believes it to be true.
When we think of adaptations that increase survival value, we normally think of changes that might make certain animals stronger or faster or better able to avoid their natural predators and the like. Consequently, when we think of a peacock, it may be hard to imagine in what conceivable situation such an excessively ornate plumage would be helpful.
The answer – I think – from the perspective of a proponent of the notion of natural selection, would be that the plumage has survival value in that it increases the attractiveness of the peacock, thus making those with larger and presumably more appealing displays of color and beauty more likely to find a peacock mate and procreate.
Again, at face value, the idea has some merit & makes a certain amount of sense. To me though, this exposes one of my frustrations with the theory. When something like an excessively ornate plumage is explained as “useful” to the bird in that it makes it more attractive, no one seems to stop and consider how decidedly unhelpful such a thing would be in other situations, or how much of a disadvantage it might be for the bird’s survival when it’s life is at stake.
Here’s what I mean, and I’m going to overstate my case to make sure that my point is clear.
I think I’m supposed to believe that peacocks were once a much more drab and dreary creature, like some kind of pheasant, maybe. Then, when some lucky little guy was born with a pretty feather or two, the ladies flocked to him and eventually there were lots of little guys out there with some pretty feathers. Over more time, peacocks with several feathers outnumbered those with only a few, and so on and so forth, until we reached our current situation where peacocks come equipped with truly magnificent spreads.
But, when I stop and think about this, it really doesn’t make sense. First, the more ornate the birds got, the more attention they’d attract. It is hard to conceive how these increasingly large displays of color don’t also alert predators to the birds presence, thus making them bigger targets. Second, the more weight these guys are carrying, the slower they’d move – presumably, making them less likely to escape the predators they’ve now attracted.
In short, it seems strange that we would consider the development of these feathers and the complications that came with them as an advance for the birds. Not only do they make the peacock more vulnerable, they are actually a form of reproductive regression. The birds used to be able to procreate without fancy plumage, apparently, but now they need all this extra stuff to attract another bird’s interest. That seems like a step back. All those “plainer” animals out there who happily reproduce with other “plain” animals seem to have a leg up on the peacocks who need such a fancy ‘get-up’ to successfully mate.
So here’s the thing. I don’t really buy it. It strikes me that Darwin’s own theory doesn’t really support peacocks developing in this way. The lesser advantage of “beauty” should have taken a back seat to the greater advantage of “speed” or “ability to blend in” so that peacocks were increasingly more durable or better equipped or whatever, rather than less. But it doesn’t seemed to have gone that way.
It seems to me that this and many other examples of variety and striking beauty in nature that doesn’t seem at all to be functionally advantageous is a problem for strict application of the law of natural selection, nor do I see how revised versions of the idea like punctuated equilibrium help. Of course, I could be wrong, but that’s how I see it.
Next time, I’ll spend some time on what bugs me about the manner in which too many Christians attack evolutionary theory and concepts, but this is enough for now.