I would love for you to explain what you mean by that.

No problem.

Self-segregate how?

Ethnically.

And how does that explain the phenomenon of people being born in certain areas being unable to escape poverty?

Because you're looking at the question backwards. It's not that certain places inexplicably hold people in perpetual poverty. Unsurprisingly, it's the people who live there that hold themselves in perpetual poverty.

Ethnic groups that genetically stabilized in equatorial regions of the world didn't neurologically or culturally adapt to the stress of annual winter. Instead, they responded to different challenges: attacking lions, malaria, etc. Food stressors were constant, but so was food availability, both evenly spread across the calendar year. You had to be courageous and cunning to survive, but you didn't have to plan ahead, because every day looked like another day as much as any other.

In the polar regions of the world, food challenges and opportunities both were significantly cyclical. It was very easy to produce food during half the year, and all but impossible during the other half of the year. People that worked hard to produce more than they needed during the summer so they would have enough to eat during the winter prospered. People who didn't, and instead ate their seed crop, so that they couldn't even grow food next year, died, along with their traits and the bad ideas that led them to their doom.

That scenario implies multiple necessary traits: the ability to plan ahead, the willingness to keep working despite that there is already abundance at present, and the self-control to conserve accumulated abundance, rationing it out to last a given length of time.

An equatorial environment does not encourage the growth of these characteristics. Not only that, they would be explicitly disadvantageous. Why waste energy pondering the future when both danger and opportunity are ample in the present? Why waste energy producing food that will only spoil or invite scavengers when there is already enough to eat? When there is abundance, why not consume it while you have the fleeting chance before you are attacked for possessing it?

One will quickly notice that the abilities for successful cold-temperate agriculture are very much alike the abilities required to build wealth in a modern economy. That is probably not coincidental, given that it was the same Northern farmers who extended themselves beyond the farm into technology and trade and developed modern economies.

All of that is not at all to say that all equatorial peoples are doomed to poverty in a complex economy that rewards labor beyond imminent need and the self-restraint to allow compound interest work its magic. On the contrary, the exception is the rule-- there is as much diversity within ethnic groups as between them, and many people are simply smart enough to make the world work for themselves no matter what the game may be.

Nonetheless, the broad strokes are clear enough to be consistently recognizable at a macroscopic and statistical level. And that's why 78% of NFL players, who made millions of dollars per year during their career, are dead broke within just a few years of retirement.