Term among zoologists for an upright posture in locomotion whereby an animal walks or runs on its two hind feet. Quite a few vertebrates beside man share this upright locomotor posture—for example, many reptiles that lived in the Mesozoic, some living reptiles, birds, and kangaroos.
^Terres, John K. (1980). The Audubon Society Encyclopedia of North American Birds. Alfred A. Knopf, Inc. ISBN0394466519.
This article is part of Project Glossary, a All Birds project that aims to write comprehensive articles on each term related to animals.