Transcript detail
Loading...
Public transcript context with linked callsigns, related nets, and analysis metadata.
Transcript
Public transcript text
And the policy is the present age. It runs from 11,000,000 years ago to the present. I hope you will see in the modern humans. They emerged about 200,000 years ago. So this shrinkage happened relatively recently. There could be a caveat to this research and that the brain size tends to be over representative of European ancestry, which make global assessments difficult. In some countries, brain size over the last 150 years in industrialized countries has gotten bigger, but this is just from limited data. So it doesn't give a full prediction. In every brain since the shrunk, the question is why? Well, it could be a number of factors. Introduction to agriculture and animal husbandry allowed humans to live in large communities. Physical strength needed for hunting, big game, and protecting families from predators became less of a necessary. Smaller body size needed.
Explore