From an email discussion:

> I was attempting to posit that energy efficiency may be an easier rule to widely apply
> than intelligence.

Efficiency is a good metric, but it encompasses a lot more than just intelligence. Aphids might be extremely efficient in obtaining food, but that doesn't mean they are extremely intelligent.

In fact, intelligence is remarkably inefficient, because it devotes metabolic energy to the ability to solve all sorts of problems, of which the overwhelming majority will never arise. This is the specialist/generalist dichotomy. Specialists do best in times of no change or slow change, where they can be…