Having two feet, not four

Usage examples of bipedal.

Most anthropologists say Australopithecus was a human ancestor with an apelike head, a humanlike body, and a humanlike bipedal stance and gait.

Ramapithecus fashioned tools, were bipedal with erect posture, and probably utilized the implements for hunting.

The earliest prosauropods were bipedal, but later forms appear to have walked either occasionally or habitually on all four legs.

Coelurosaurs were small, bipedal meat eaters with narrow skulls and large eyes, long arms with grasping hands, and slender hind legs.

Associated with this size increase is the tendency to be bipedal rather than quadrupedal.

These bipedal dinosaurs had very short forelimbs, but their unique feature was the unusual thickness of their skull roofs, which in several Late Cretaceous forms are fused into a single massive element forming a high dome.

All other saurischian dinosaurs make up the bipedal carnivorous theropods.

The employment of the forelimbs, especially in bipedal forms, for manipulative functions constitutes a further anatomical change favoring their success.

Dinosaurs living in the oases now preserved in the Navajo Sandstone were generally small, bipedal desert specialists.

However, in the Peace River Canyon, one layer of rock showed a large group of bipedal herbivores moving together in one direction, and changing the trend of direction as they went along.

By that trick, we ceased being two bipedal strangers and became a single honorary hadrosaur.

Recently, Kevin Padian has noted a similarity between the hind limbs and feet of pterosaurs and dinosaurs, suggesting that they may have been bipedal, walking only on their hind legs.

Second, modern experiments have shown that bipedalism does not increase energy efficiency, and as more fossils have been found we now recognise that early bipedal apes lived in environments where trees were plentiful.

In these circumstances, Nina Jablonski and George Chaplin, of the California Academy of Sciences, have suggested that the real reason humans became bipedal was as a way to appear bigger and more threatening in contests with other animals, and in so doing avoid punishing conflicts and gain access to food.

Running a hand under my shirt, the ridges and depressions I encountered along my ribs felt like some kind of bipedal armadillo.