I think human intelligence owes a lot to environment. Necessity is the mother of invention. Pre homo sapien populations which existed in harsh environments had to be smart to survive. They used their brains to survive and over time general intelligence increased. It's from these beings we are descended. The great migration out of Africa was likely born of attempting to find a more amenable, safe and abundant place to live. This is ongoing. An existential threat makes people think hard. Of necessity we invent ways to overcome/ extricate ourselves from danger. Curiosity, abstract thought has it's basis in a desire to gain the most from our environment in order to live better and longer.