[Right Wing Professor]

But the tribe consisting of any strain of bacteria learns through evolution, in a way that is functionally equivalent to the trial and error learning observed in organisms having nervous systems.

I think that's a unwarranted broadening of the word 'learning', which ususally means the long-lasting change of behavior of an individual in reponse to stimuli. In evolution; some die and some don't, and the population changes, but no individual changes.

[js1138]

Your caution is warranted, but then I consider learning to be a change in the probability of behavior. I think this kind of change can be mapped to the change in allele frequency characteristic of evolution.

This is just a conjecture, but there are lots of folks in experimental psychology who support it.