Humanity's Ancestors Took to Two Feet For an Entirely Different Reason Than We've All Been Told: A Study

Hominins, the early forebears of humanity, may have started walking upright in order to better navigate the rugged landscape of East and South Africa, according to a controversial new study published in the journal Antiquity.

Up until now, scientists have largely agreed that bipedalism grew out of a response to climatically-driven changes in vegetation – mainly that of fewer trees and more grasslands that required height to see across.

But researchers at the University of York and the Instiut de Physique de Globe go against the accepted theory, claiming instead that rough terrain created by volcanoes and shifting tectonic plates would have made it highly inconvenient for the human ancestors to remain on all fours.

“The broken, disrupted terrain offered benefits for hominins in terms of security and food, but it also proved a motivation to improve their locomotor skills by climbing, balancing, scrambling and moving swiftly over broke ground – types of movement encouraging a more upright gait,” Isabelle Winder, an archaeologist and one of the paper’s authors, said in a press release.

Furthermore, the researchers found in their investigation, those who began to move in a more upright fashion had the added benefit of two available limbs, which then served to increase manual dexterity and tool use, both of which served as a key stage in the story of evolution.

Nor does it stop there.

“The varied terrain may have also contributed to improved cognitive skills such as navigation and communication abilities, accounting for the continued evolution of our brains and social functions such as cooperation and team work,” Winder said.

As far as the development of running adaptations to the skeleton and foot, the scientists hypothesize that these developments came from later excursions into the surrounding flat plains in search of prey and new home ranges.

In the end, Winder said, the theory “offers a new, viable alternative to traditional vegetation or climate change hypotheses. It explains all the key process in hominin evolution and offers a more convincing scenario than traditional hypotheses.”