Humans’ ability to walk upright on two legs may have evolved in trees, rather than on the ground, according to scientists studying wild chimpanzees in Tanzania. This contradicts the widely ...

Human bipedalism -- walking upright on two legs -- may have evolved in trees, and not on the ground as previously thought, according to a new study. Human bipedalism -- walking upright on two legs ...

Rhianna Drummond-Clarke When human ancestors evolved to walk upright, they may have done so in trees, suggests new research published Wednesday in the journal Science Advances. The findings ...

The National Christmas Tree in front of the White House is standing upright again after gusty winds toppled it Tuesday. The National Park Service said the tree fell over around 5 p.m. following a ...