Jul 23 2009
Progress by Loss and Myths of Evolution
Evolution has been, and still sometimes mistakenly is, portrayed as a grand parade to the new, the better, the more complex. But two things, at least, make this flatly untrue.
First, the failures are an undeniable yet indispensable part of the parade. Sure, they tend to be fleeting and thus partly invisible — joining the parade for a mere half block before veering off to nowhere — but to overlook them is sheer folly. The numbers, were we to count them, are staggering.
Second, there is no force pushing evolution inextricably toward the bigger and the better. None that seems more than a human projection, in my opinion. Consider this recent science news headline:
Male Sex Chromosome Losing Genes By Rapid Evolution, Study Reveals.
That’s right, the male “Y” has been losing size (and hence complexity) over time. It’s shrinking. And not due to immersion in cold water.
With evolution, whatever works in one form or another, persists. Whatever doesn’t, disappears. Sometimes. If we are talking organisms, that is absolutely true. But non-working (non-functional) characteristics of organisms can persist if there is no cost the selective pressures can subtract. Sometimes.
I’m not an evolutionary biologist, so don’t take my word for it. I also wouldn’t advise taking any single thinkers word for anything. I suggest aiming for a deeper education.
