Bernard,
This NY Times article is terminally polluted with anthropomorphic, wind-god-like descriptions of birds developing brilliant strategies to adapt to climate change.
But its real content can be completely captured in two simple observations:
- Because sexual reproduction randomizes offspring, some progeny will happen to nest earlier than usual, some other progeny will happen to prefer higher altitudes, yet other progeny will happen to behave in some other different way, and so forth.
- Birds that happened to nest later than usual would have tended to lose eggs to overheating and not reproduced effectively. Birds that happened to prefer lower altitudes and warmer temperatures also would have tended not to reproduce effectively. And so forth. Those lineages tend to fall away, get subtracted.
Life on our planet is sun-driven, randomly-varying replicating processes thrown at a usually-slowly-randomly-varying planetary environment.
The basic mechanism of evolution is far simpler than we stuck-in-the-adaptation-and-selection-metaphor humans tend to make it.
Now, here are the same two observations, this time in the context of evolutionary software development with purpose-driven artificial selection:
“Evolutionary computing uses a different approach [from machine-learning neural nets]. It starts with code generated entirely at random. And not just one version of it, but lots of versions, sometimes hundreds of thousands of randomly assembled pieces of code.
“Each of these codes is tested to see whether it achieves the required goal. And of course, all the code is awful because it is randomly generated.
“But just by chance, some pieces of code are a little better than others. These pieces are then reproduced in a new generation of code, which includes more copies of the better codes.
“However, the next generation cannot be an identical copy of the first. Instead, it must change in some way. These changes can involve switching two terms in the code—a kind of point mutation. Or they can involve two codes that are cut in half and the halves exchanged—like sexual recombination.”
Evolution is conceptually simple. Its essence is randomization during reproduction. Period. And specifically not anthropomorphic adaptation and/or natural selection.
You might ask, where then is natural selection? Well, it’s here, always here, but not as a force or an agent. To exist is to persist through time within an external environment. That environment comprises the selective agent. But it exerts no force and does not itself act. So “agent” is the wrong noun, and “select” is the wrong verb. The environment, whatever happens to be in it, is the context within which a living being persists (or not) and reproduces (or not). The environment as a whole is mute, uncaring, passive. For the standpoint of any one living being, the environment might be either thoroughly benign or instantly deadly, either frictionless or terminal.
Wayne