How humans became upright: key changes to our pelvis found
Genetic and anatomical data reveal how the human pelvis acquired its unique shape, enabling our ancestors to walk on two legs. Originally published by Katie Kavanagh , on 27 August 2025 All vertebrate species have a pelvis, but only humans use it for upright, two-legged walking . The evolution of the human pelvis, and our two-legged gait, dates back five million years , but the precise evolutionary process that allowed this to happen has remained a mystery. Now, researchers have mapped key structural changes in the pelvis that first enabled early humans to walk on two legs, and to give birth to babies with large brains and broad shoulders . The study , published in Nature on 27 August 1 , compared the embryonic development of the pelvis between humans and other mammals . They found two crucial evolutionary steps — related to the growth of cartilage and bone in the pelvis — that put humans on a separate evolutionary path to that of other apes. “Everything from the ba...