form of terrestrial locomotion where an organism moves by means of its two limbs or legs From Wikipedia, the free encyclopedia
Bipedalism is a form of movement on the ground. Some tetrapods have evolved the ability to move on two limbs. Those that do, use their rear limbs. Some animals move on two limbs all the time, they are called habitual bipeds. Optional bipeds can move on two or four legs.
Early quadruped animals used all four limbs for locomotion but many later ones are bipedal. The earliest dinosaurs were bipedal but millions of years later some reverted and became quadrupeds. Birds are descendants of bipedal dinosaurs, and are bipeds themselves. Their forelimbs have become wings.
Some optional bipeds stand on two legs to drive away competitors and predators, to see farther, or as body language. Their locomotion is on four limbs.
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.