title: Locomotor economy and the origin of bipedality: reply to Steudel-Numbers.
authors.affiliation: Department of Anthropology, Northwestern University, Evanston, Illinois 60208, USA. w-leonard1@northwestern.edu
authors.forename: W R
authors.initials: WR
authors.lastname: Leonard
authors.forename: M L
authors.initials: ML
authors.lastname: Robertson
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D000885:Anthropology, Physical; D005075:Biological Evolution; D004734:Energy Metabolism; D005260:Female; D015186:Hominidae; D006801:Humans; D008124:Locomotion; D008297:Male; D011187:Posture; D012737:Sex Factors; D016138:Walking