delinquent noun [C]. âº a âperson, usually âyoung, who âbehaves in a way that is âillegal or not âacceptable to most âpeople: âjuvenile delinquents.
Sahelanthropus may have walked on two legs. The oldest evidence for walking on two legs comes from one of the earliest humans known, Sahelanthropus. Walking upright may have helped this species survive in the diverse habitats near where it livedâincluding forests and grasslands.
Answer Wiki. Because two legs take less energy to walk and run than using four legs. Another theory considers the efficiency of upright walking. In the 1980s, Peter Rodman and Henry McHenry, both at the University of California, Davis, suggested that hominids evolved to walk upright in response to climate change.