Ancient human body size linked to climate change

Temperature may have driven fluctuating body sizes across human history.

Three Homo skulls and two thigh bones.
Human fossils from the Pleistocene, illustrating the variation in brain and body size. Skulls – Neanderthal [left], Homo sapiens [middle], Middle Pleistocene Homo [right] and body size. Thigh bones – Middle Pleistocene Homo [top] and Neanderthal [bottom]. Credit: Dr Manuel Will.