[metalman]

the problem is that humans are modifying the environment, orders of magnitude faster than evolution can keep up with, and many of the "features" of our modern technological cities are prouncedly geared towards our worst/best (non) survival instincts, as from an evolutionary perspective we are all living in the valley of infinite plentitude, and survival of the fittest has taken on an entirely other definition.

[inigyou]

Evolution doesn't find a solution to a problem. Instead, it finds all possible solutions. Ones which don't fit through the problem are culled.

During happy times, mutation creates a variety of individuals. During stressful times, individuals who happen to have traits that help them weather the stress are the ones who survive more. Sometimes much more. That's when the evolution happens.

Both parts can happen concurrently and gradually, like those butterflies who turned black to hide in coal smoke.

[lotsofpulp]

>Both parts can happen concurrently and gradually, like those butterflies who turned black to hide in coal smoke.

Do you mean the black ones survived and procreated?

[inigyou]

Yes, but gradually. The blacker ones reproduced more. There weren't any black ones at the beginning

The opposite is the Black Death. Some people had more aggressive immune systems that were able to destroy the bacteria before it destroyed them. This is thought to have caused a jump increase in the "immune aggressivity" of European populations, causing more autoimmune diseases in subsequent generations.