Bipedalism
Bipedalism is the condition of having or using only two feet for locomotion[1]. This form of movement is found in a few groups of animals on Earth. Throughout the course of evolutionary history, the use of bipedal movement came forward several times as an adaptation to the environment, including a a point in human evolutionary history.
The use of bipedal movement is thought to be a key element in human evolutionary history, as it is part of what separates humans and their ancestors from the other Great Apes.
Species Displaying Bipedal Movement
There are many species on Earth that use bipedal movement as their primary means of terrestrial locomotion, and also some that can use bipedal movement when pressed to escape danger.
Birds
Lizards
Primates
Genus Homo
Anatomical Correlates in Humans and Bipedal Human Ancestors
Through looking at the osteology of humans and their close relatives in the fossil record, a few key anatomical traits for the particular bipedalism associated with humans have come forward. A combination of these traits makes it possible for humans to walk upright and allows scientists to diagnose whether a fossil likely used bipedal movement or not.