Drilling in an African Lake to Find Out Whether Climate Change Drove Human Evolution

Abstract

Why does drilling into a dried-out lake in eastern Africa get scientists excited? Simple answer: the lake’s sediments store valuable information about how past climate change shaped the environment where our earliest ancestors lived. Those sediments serve as a natural record of Earth’s ancient climate. While much is known about human evolution from fossil discoveries in eastern Africa, the role that climate change might have played for human biological and cultural evolution remained unclear for a long time. But now we have drilled 278 m into the ground at the bottom of the old Chew Bahir Lake in southern Ethiopia, which has given us some detailed answers. This natural record covers the last 620,000 years of climate history from one of the proven habitats of ancient Homo sapiens, and it can help us to unravel connections between climate and human evolution.