So, I was happily reading along in a book I was REALLY enjoying. Like, couldn't put down. It is a great fantasy, and I was happily devouring it. And then, duhn, duhn, duhhhhnnnnn, the author decided that her fantasy creatures needed a scientific base. And royally messed it up. Like, made me want to throw the novel across the room messed it up. (Yeah, I get a little emotional over science stuff, I mean, I *am* a science professor...okay, yeah, I know, I need help....)
Anyhow, yeah, it was the whole "mutations can be induced where and when we want them because we *need* them to be here or we'll go extinct." Um. No. Just, no. Anyhow, I figured I'd re-run this post for funsies and maybe you all will get a little out of it, or just remember that I'm always here for random genetics-related questions for your WIPs (not that I'm like all-knowing or anything, but I do know lots of scientists!).
Okay, so for today's Science Sunday post I thought I'd hit on a topic that seems to be regularly misrepresented in general science stuff on TV and in books. Just this week I saw it messed up in a book I was reading (I won't get into which one, but I've already reviewed it here<--see, long history of this bugging me, lol!) and in an episode of the X Files (yeah, I love that show and watch reruns all the time, but sometimes Mulder gets a little jacked up when it comes to basic evolutionary theory).
So, here's the low-down: mutations are random. This means new adaptations that are based on the changes that these mutations create are random. And just because we NEED something to happen in order to survive, well, we can't make that happen just because we want it to. Confused? Let me give an example:
|Le sigh, this is just dumb....|
In reality, the only way humans would survive this kind of situation would be if someone, somewhere had already had this random mutation (or was born with it in time to make use of it) and this random event allowed them to survive, have offspring, and pass along that mutation for gills (something that was probably pretty hard, seeing as how A. they're probably the only one on earth with gills, and B. human "gills" aren't really gills in the sense that work that way, but whatever, it's just an example).
Hopefully that makes sense :)
Just because we need, want, or would find a particular ability totally useful doesn't mean we're going to get it. We are constrained by the random nature of whatever mutations occur in our DNA that produce a different phenotype (or outward expression of the genes or genotype) and the right kind of situation that will allow for selection of that phenotype, so that it becomes more common in the population through natural selection.
There has been some recent research into this using bacteria and mutations that allow them to process types of food that were usually harmful or poisonous to them, and finding ways to survive, but the underlying principle is the same: the mutation that allows for the bacteria to feed off something new is still random and not "induced" by the environment.
Next time maybe I'll go into the awesome world of Punctuated Equilibrium, another topic that Mulder clearly needs some schooling on... :)