[Asooka]

Hm, then shouldn't people who live in tribal societies as hunter gatherers have bigger brains still? Has anyone studied that?

[algebraically]

I don't know. That's a good question but most modern humans are essentially clones so I don't think there is going to be much difference. [1][2]

1: https://www.nationalgeographic.org/media/genetic-bottleneck/

2: https://en.m.wikipedia.org/wiki/Toba_catastrophe_theory

[misja111]

If you read the article you will find that your question is answered in there.