How to Live in the Harshest Place on Earth

TL;DR

The Turkana people survive extreme desert conditions through a gene variant (STC1) that evolved 350 generations ago to handle high-protein diets and chronic dehydration.

Key Points

• 1.The Turkana of northwest Kenya live under extreme conditions few humans match. Their diet is 70–80% animal products — meat, milk, and blood — delivering 300% more protein than WHO recommendations, while nearly 90% test positive for chronic dehydration.
• 2.A specific genetic adaptation called STC1 appears to make this lifestyle viable. An enhancer region in Turkana DNA boosts STC1, a gene that helps process purine waste from meat and concentrates urine to conserve water — precisely what's needed in their environment.
• 3.This adaptation traces back ~350 generations to Africa's aridification. Researcher Julien Ayroles found the timing of STC1 selection coincides with the Turkana's ancestors migrating southward as northern Africa became the Sahara desert around 5,000 years ago.
• 4.Urban Turkana show gene expression changes that raise chronic disease risk. The evolutionary mismatch hypothesis predicts — and the data supports — that Turkana moving to cities experience metabolic shifts linked to heart disease and diabetes, conditions previously rare in their community.
• 5.The study is a rare clean test of evolutionary mismatch because all subjects share the same ancestry. Unlike comparisons between Europeans and hunter-gatherers, researchers can compare pastoral vs. urban Turkana within one genetic background, with ~5,000 participants across 80 communities enrolled.