I don't know which article thetli8 is referring to, but this might be a good place to start an investigation: https://en.wikipedia.org/wiki/Chronotype https://

I don't know which article thetli8 is referring to, but this might be a good place to start an investigation: https://en.wikipedia.org/wiki/Chronotype https://en.wikipedia.org/wiki/Chronotype > I'm quite skeptical of the concept of humans "evolving" different time-preferences As described in the wiki link above, the differences in "time-preference" are basically down to natural variance - I don't believe there's any evidence of a bi-modal distribution. Nature does seem to select for anti-fragile populations (because by definition they are robust) and one way of achieving this is to have a certain amount of variability in phenotypes.