More about how evolution works (Evolution)

by dhw, Tuesday, October 13, 2015, 12:42 (3327 days ago)

My thanks yet again to David, who has posted two items on fruit flies and guppies which once more raise the question of how evolution works.-Re fruit flies: QUOTE: “.....this finding opens up a whole new set of questions about how animals behave and react to their environments."-David's comment: This looks like a learned behaviour that became an instinct. Family planning with food source.-I would put this on a par with other “nature's wonders” which in the past you have attributed to divine planning. Like the parasitic wasp, the weaverbird's nest, the monarch's lifestyle etc., it must have started somewhere. Perhaps this “learned behaviour” stems from experiments which worked, and so the successful “wonder” is passed on and becomes the way things are done (a bit like our traditions and conventions). The premise would be that fruit flies are not machines but thinking beings, and they use whatever materials are at their disposal to investigate ways in which they can best cope with the environment. Whatever works stays (natural selection).-Re guppies: QUOTE : "Our research shows that these fish adapted to their new habitats in less than one year, or three to four generations, which is even faster than we previously thought,” said Gordon...-QUOTE: “'People think of evolution as historical. They don't think of it as something that's happening under our nose. It is a contemporary process. People are skeptical; they don't believe in evolution because they can't see it. Here, we see it. We can see if something makes you better able to make babies and live longer,” Reznick said.-David's comment: No question that random chance mutation/natural selection occurs, as above, but it is not present enough to drive evolution in the time scales we know.-I agree with you, but would stress that the two quotes above only concern adaptation and not innovation, which is why people think of evolution as historical: nobody has observed or can explain innovation, whereas the guppies are still guppies. However, adaptation may hold the key to innovation. If we are sceptical of the notion that God preplanned the guppy's every possible response to every possible environmental change, or personally intervened to enable it to adapt, we are left with the hypothesis that the cell communities within the guppy make all the necessary adjustments. They are confronted with a new problem, they process the information that comes to them from outside, and they communicate and cooperate with one another in working out how to deal with it. These are manifestations of intelligence. And once you attribute intelligence to organisms, you open up the possibility that as well as adapting, they may also be capable of innovating.