I’d say that intelligence variations are more visible in (modern) humans, not that they’re necessarily larger.
Let’s go back to the tribal environment. In that situation, humans want to mate, to dominate/be admired, to have food and shelter, and so on. Apart from a few people with mental defects, the variability in outcome is actually quite small—most humans won’t get ostracised, many will have children, only very few will rise to the top of the hierarchy (and even there, tribal environments are more egalitarian that most, so the leader is not that much different from the others). So we might say that the variation in human intelligence (or social intelligence) is low.
Fast forward to an agricultural empire, or to the modern world. Now the top minds can become god emperor, invading and sacking other civilizations, or can be part of projects that produce atom bombs and lunar rockets. The variability of outcomes is huge, and so the variability in intelligence appears to be much higher.
I’d say that intelligence variations are more visible in (modern) humans, not that they’re necessarily larger.
Let’s go back to the tribal environment. In that situation, humans want to mate, to dominate/be admired, to have food and shelter, and so on. Apart from a few people with mental defects, the variability in outcome is actually quite small—most humans won’t get ostracised, many will have children, only very few will rise to the top of the hierarchy (and even there, tribal environments are more egalitarian that most, so the leader is not that much different from the others). So we might say that the variation in human intelligence (or social intelligence) is low.
Fast forward to an agricultural empire, or to the modern world. Now the top minds can become god emperor, invading and sacking other civilizations, or can be part of projects that produce atom bombs and lunar rockets. The variability of outcomes is huge, and so the variability in intelligence appears to be much higher.