Human Ancestors Suddenly Got Bigger Around 2 Million Years Ago — With Average Body Size Jumping From 88 to 132 Pounds

Human Ancestors Suddenly Got Bigger Around 2 Million Years Ago — With Average Body Size Jumping From 88 to 132 Pounds

Learn how fossils show human ancestors did not grow bigger in a straight line, but split into larger and smaller evolutionary paths.

Bigger Human Bodies Evolved Late, Study of Fossils Finds

New PNAS research on 386 fossils shows human body size jumped later within the genus Homo rather than growing steadily across the whole family tree.

Study Reveals Major Body Size Jump Within the Genus Homo

The biggest jump in body size among our ancestors happened around 2 to 2.5 million years ago, with the appearance of Homo rudolfensis or Homo erectus/ergaster, rather than gradually across the whole human family tree.

Why Human Body Size Leaped 2 Million Years Ago

Human body size evolution was not a linear progression. Instead, a massive body mass explosion occurred 2 to 2.5 million years ago with Homo erectus, while divergent species like Homo floresiensis maintained a smaller, child-sized stature.