Re: IS A NEW THEORY OF EVOLUTION NEEDED?

On 28/03/2024 03:28, John Harshman wrote:

Going back to the real issue though, I'm not sure it's quite what they mean
with niche construction - at least the way I understand them - because there is no feedback loop from the effect that the bear has on its environment and subsequent selection pressures. IIRC the example we got in school were beavers: they are adapted for semi-aquatic life, AND create more
semi-aquatic environments through their building activity which then again acts
on the beaver and increases the pressure on those less well adapted etc. Or humans. -NS is different in an environment with hospitals than one without
>

I had viewed the term as less restrictive, such that any alteration of behavior in turn altering the selective environment experienced by the organism would count. Darwin leaves open the question of whether change in phenotype or of behavior comes first, but he also suggests mutual feedback between the two. My notion was that it's not the physical environment that counts but the environment as experienced by the organism. Thus a change of food source could count. That would certainly increase the impact of niche construction on evolution and greatly increase the number of examples, which would otherwise be fairly few.

Evolution has a number of feedback loops - between species (arms races), between the two sexes of a species (sexual selection), between organisms and the environment (niche construction), ... It'd be nice to operationalise our understanding of these processes, but I doubt that rises to a new theory of evolution.
25 years ago chaos was a hot topic, and Kauffman's research program had hopes of bringing self-organisation into the centre of evolutionary theory. That, if successful, would have, I think, been a bigger change.
--
alias Ernest Major