Origin of Human Bipedalism As an Adaptation for Locomotion on Flexible Branches

2007/05/31 by Susannah K. S. Thorpe, R Holder, Robin H. Crompton · 11 citations
Psychology · Earth and Planetary Sciences · Environmental Science · #Primate Behavior and Ecology #Evolution and Paleontology Studies #Amphibian and Reptile Biology

paper · doi:10.1126/science.1140799

openalex publication_date 2007/05/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29

Abstract

Human bipedalism is commonly thought to have evolved from a quadrupedal terrestrial precursor, yet some recent paleontological evidence suggests that adaptations for bipedalism arose in an arboreal context. However, the adaptive benefit of arboreal bipedalism has been unknown. Here we show that it allows the most arboreal great ape, the orangutan, to access supports too flexible to be negotiated otherwise. Orangutans react to branch flexibility like humans running on springy tracks, by increasing knee and hip extension, whereas all other primatesdothe reverse. Human bipedalism is thus less an innovation than an exploitation of a locomotor behavior retained from the common great ape ancestor.

Citations

• Asa Issie, Aramis and the origin of Australopithecus

Cited by

• Independent evolution of knuckle-walking in African apes shows that humans did not evolve from a knuckle-walking ancestor
• Bipedal and quadrupedal locomotion in chimpanzees
• Bipedality and hair loss in human evolution revisited: The impact of altitude and activity scheduling
• The evolution of the upright posture and gait—a review and a new synthesis
• Origins of Bipedalism
• Spinopelvic pathways to bipedality: why no hominids ever relied on a bent-hip–bent-knee gait
• Orrorin tugenensis Femoral Morphology and the Evolution of Hominin Bipedalism
• Human-like hip joint loading in Australopithecus africanus and Paranthropus robustus
• Calcar femorale variation in extant and fossil hominids: Implications for identifying bipedal locomotion in fossil hominins
• Australopithecus [wikipedia]
• Bipedalism [wikipedia]