Question Process of Evolution

First, let me say I'm not a scientist, which will probably become abundantly clear through the progress of this post. However, I've been curious about the process of adaption to a changing environment and was wondering if anyone could straighten me out on it. It seems that when an environmental change occurs - such as whatever event brought about the demise of the dinos - opportunistic species begin to evolve to adapt to the changed/changing environment. What triggers that change? How does the body 'know' what changes (i.e., longer legs, plate armor, shorter muzzle, larger brain capacity) to make for that particular environment? I'm thinking of a correlation between this and the body's reaction to disease. For instance, I'm infected with chicken pox. My body launches an immune response against chicken pox, specifically - is that correct? The antibodies against chicken pox are not the same as those against polio or some other virus, right? (Here's the part where you really discover I'm not a scientist!) How does the body know to make antibodies specific for the invading virus? I'm wondering if there is some sort of biochemical trigger, some kind of 'body knowledge' contained in our cells that would make a species mutate to adapt to a specific environment - almost an immune response to the 'disease' of an environmental change. Just as our body wouldn't start producing polio antibodies to fight chicken pox, neither would our bodies (or rat bodies or whale bodies, or whatever) produce heavy fur coats in response to a hotter environment, for instance. I understand the theory - that multiple mutations occur randomly, and those that work ,survive, and those that don't (such as a heavy coat in heat), aren't successful. But it seems to be that some evolution happens quickly and does not seem to be quite so haphazard as all that (aren't plants and animals mutating to adapt to the environment around Chernobyl - believe I read that somewhere). Time alone might not allow for lengthy natural 'experimentation'. That's why I'm curious if there has been any thought about an 'evolution gene' triggered by environmental stress, or some sort of body 'knowledge' similar to that possessed by the immune system? Sorry for the long post, hope I haven't made an idiot of myself with my probably very ignorant question.

'First, let me say I'm not a scientist, which will probably become 'abundantly clear through the progress of this post. However, I've been 'curious about the process of adaption to a changing environment and 'was wondering if anyone could straighten me out on it. 'It seems that when an environmental change occurs - such as whatever 'event brought about the demise of the dinos - opportunistic species 'begin to evolve to adapt to the changed/changing environment. What 'triggers that change?

The absense of preexisting better adapted organisms which would otherwise outcompete them into starvation. For further detailed info, try the talk.origins evolution faqs. You can think of all organisms as constantly pushing at the edge of their niches, and as soon as a neighbouring organism ceases pushing back, bloop, they expand to take advantage of the new space.

No, there isn't any 'mutator gene' that responds to the environment. {except something in bacteria, see below}. Not enough time for natural experimentation? That must be why 99% of all species that ever were are extinct. Adaptation around Chernobyl? Be cautious about you believe... but evolution can be faster than perhaps you think. Your question about antibodies is complicated, and not part of evolution in the ordinary sense. Try an encyclopeadia to get a start on it. Bacteria, under some conditions, may switch to a method of cell division that requires less energy because it skips some of the error checking on DNA that normally happens. To pursue this subject, try the news group sci.bio.evolution.

Talk.origins Archive http://www.talkorigins.org/

Regards David Ramalho

Well, i understand evolution not as the adaptation of the organism to a new enviroment. The best idea is a change in both (enviroment and organisms) at same time, and the change of the organism can be of diferent ways, but the ways of change that are better to the enviroment (that is changing too) are the ones who will survive. This is the way that allow the diversification of species.

That's all i have to say, and if my english is not too good, i' sorry it will be better.

Alejandro Sanchez