2005-09-23

Evolution at Home

Much to my chagrin, my snail tank appears to have become a prolific fruit fly breeding ground. Now, there's no way for me to permanently solve this problem, that I can think of. I can clean the tank, but as soon as I do, some of the many flies that have escaped will get back in and start breeding again. And I can't effectively get rid of the population outside the tank with newly hatched flies coming out of the tank at a steady pace. My only hope is to do my best to encourage any fruit flies in the tank to leave, and then try to reduce the population outside the tank to manageable levels. I would try putting the tank outside for a couple days but it's supposed to be in the teens and low twenties and I'm afraid that would kill the snails (10tacle, care to weigh in on this?).

So. To get rid of insects inside the apartment the safest, cleanest, cheapest, and most effective way to do this is with diatomaceous earth. It's best suited for walking insects, but it also works with flying ones, just more slowly. The primary disadvantage to this method is that it makes your apartment look like a five-year-old has been scribbling on bits of it with chalk. Much as this may fit in with my decor theme (mess, mess, and more mess), I'd rather avoid it, so I decided to start with some very clever fruit fly traps a friend told me about.

You take some small, shallow bowls, fill them most of the way with a liquid the fruit flies will like (I used hot chocolate - dairy free so it wouldn't stink), and cover them with saran wrap. Then cut a slit in the saran wrap, so the flies can get in but, because they're flies and therefore stupid, can't get out again.

Well I tried it, and the damn things work like a charm. The two in the living room and one in the bathroom are filling up with flies (don't ask me what the flies are doing in the bathroom, where there's never any food. Flies are stupid). The one in the kitchen is still pretty empty but the kitchen is actually where the problem is least serious, so that's okay.

In observing my little fly traps, though, I noticed something. I appear to have two kinds of fruit fly. Anyone with high-school level biology (and probably most people without) will be able to guess what the two kinds are. Yup, red-eyed fruit flies and black-eyed fruit flies. BUT, I noticed something else. Now, I don't know if these traits are generally linked, or if it's just a coincidence of my populations, but the red-eyed fruit flies are tending to be less than half the size of the black-eyed ones. What this means is that the little buggers can make their way out of the traps. So while the traps are filling up quite nicely with large (relatively speaking), black-eyed fruit flies, they're just providing most of the little rede-eyed ones with a nice snack. Sure, a few of the stupider, less lucky red-eyed ones die, and a few of the smaller, luckier, black-eyed ones escape, the overwhelming majority of dead flies are the black-eyed ones. I predict that, although I started off with a large majority of black-eyed flies, in a couple days I will end up with a population that is overwhelmingly red-eyed and small flies. So what, you may ask, it shouldn't make a difference what color/size the flies are. But you'd be wrong! What, I ask you, is the defining characteristic of these red-eyed flies? It's not their eye colour, or even really their size (although that's relevant). It's their ability to survive my traps. In laying out these traps I am, pretty much by definition, creating an environment that selects for flies that can survive those traps, thereby making the resulting population harder to kill. To put it in more familiar (though less accurate) terms, I've created trap-resistant flies. Well damn.


And this evolution, yes evolution, of the fruit flies in my apartment is a fact. Not a theory, but a directly observable FACT. And anyone who can observe this phenomenon and not realise that the same forces driving it exist in nature, not realise that when you come down to it, the world we have (maybe not the exact world we have, but a world that shares the key property of being teeming with hugely varied life) is the highly likely, possibly INEVITABLE, result of the advent of a molecule that just happens to replicate itself (which in and of itself isn't a particularly surprising occurrence when you think of the sheer size of the universe) is a COMPLETE and UTTER MORON!!


(Sorry, I try not to get that heated on my blog generally. I guess I've been reading way too much Creationist nonsense lately.


Frakking dumsnuts.)

UPDATE:
In response to Q. Pheevr's response in the comments: It's true that this specific example is one of not-so-natural selection, rather than speciation, but speciation is the obvious and inevitable result of this process being repeated over and over, with multiple simultaneous selection forces, over a long period of time. There's no logical way around that, and it's the people who can't see that who are morons.

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