[HarHarVeryFunny]

> Evolution happens at the individual level

I don't think that's the right way to think about it. Genetic variation originates at an individual level, but "evolution" (differentiated survival of genetic variants) mostly happens at population level after genetic changes have spread among the population. In particular this is the case with "punctuated equilibrium" that has been observed in the fossil record (long periods of stability, interspersed with short periods of rapid change).

What happens is that many genetic variations are subtle and don't have an immediate survival benefit to the individual, so will just accumulate in the population as a whole as they are spread by breeding. Once in a while some environmental change occurs (famine, drought, disease, new predator, etc/etc) that may make a set of accumulated genetic changes, previously benign, now become more important to survival. With multiple sub-populations of the same species that have genetically drifted apart over multiple generations, some will now become more successful than others in this new (changed environment) evolutionary landscape.

Ultimately this sub-population genetic drift may lead to inability of these sub-populations (e.g. plains elephants vs forest elephants) to interbreed, and then no-going-back speciation has occurred, and further drift is guaranteed (due to no interbreeding to merge genetic changes).

[tsimionescu]

I think this is a fair criticism, and excellent explanation of evolution.

I should have expressed myself more carefully. What I am thinking of is that each individual is essentially one training step, where the current model is confronted with the training data (in this case, the entire environment, including other members of the population). Or even multiple moments over the life of the individual might be considered distinct training steps, where the model is adjusted in minute ways (epigenetics) based on certain events.

Of course, this makes less sense for species that are highly communal, such as bees, ants, or termites, where the fitness of an entire population is highly interconnected, and even severe maladaptations in an individual can nevertheless be an improvement to the fitness of the overall population (e.g. sterility in the vast majority of individual bees and ants is not a detriment, when it is a fatal flaw in almost all other animals).