That is, when we discard our experiences and look at claims as if through new eyes, what do we find when we look at evolution? I Believe we can find a great deal of common ground with this question, because when I discard my experience as an animal breeder, when I discard my knowledge, and what I've been taught, I might look at evolution with the same skepticism as someone who has either never been taught anything about it, or someone who has been taught to distrust it.
Personally my mind goes to the keratinised spines on the tongues of cats. Yes, cats have fingernails growing out of their tongues! Gross, right? Well, these particular fingernails have evolved into perfect little brushes for the animal's fur. But I think of that first animal with a horrid growth of keratin on its poor tongue. The poor thing didn't die immediately, and this fits perfectly with what I said about two steps back paying for one forward. This detrimental mutation didn't hurt the animal enough for the hapless thing to die of it, but surely it caused some suffering. And persevering thing that he was, he reproduced despite his disability (probably in a time of plenty that allowed that). But did he have the growths anywhere else? It isn't beyond reason to think of them protruding from the corners of his eyes or caking up more and more on the palms of his hands. Perhaps he had them where his eyelashes were, and it hurt him to even blink. As disturbing as my mental picture is of this scenario, this sad creature isn't even as bad off as this boar, whose tusks grew up and curled until they punctured his brain.
This is a perfect example of a detrimental trait being preserved because it doesn't hurt the animal enough to kill it before it mates. So we don't have to jump right from benefit to benefit. The road to a new beneficial trait might be long, going backwards most of the way, and filled with a lot of stabbed brains and eyelids.
Walking backwards most of the time, uphill both ways, and across caltrops almost the entire trip?
I have to admit, thinking about walking along such a path sounds like, at very least, a very depressing way to get from A to B. I would hope there would be a better way.
