Evidence that humans evolved from a knuckle-walking ancestor

  title={Evidence that humans evolved from a knuckle-walking ancestor},
  author={Brian G. Richmond and David S. Strait},
Bipedalism has traditionally been regarded as the fundamental adaptation that sets hominids apart from other primates. Fossil evidence demonstrates that by 4.1 million years ago, and perhaps earlier, hominids exhibited adaptations to bipedal walking. At present, however, the fossil record offers little information about the origin of bipedalism, and despite nearly a century of research on existing fossils and comparative anatomy, there is still no consensus concerning the mode of locomotion… 

Independent evolution of knuckle-walking in African apes shows that humans did not evolve from a knuckle-walking ancestor

The presence of purported knuckle-walking features in the hominin wrist can be viewed as evidence of arboreality, not terrestriality, and provide evidence that human bipedalism evolved from a more arboreal ancestor occupying the ecological niche common to all living apes.

Are Humans Descended from a Knuckle-Walking Ancestor?

The evidence for and against the hypothesis that humans have descended from a KW ancestor are evaluated, with some evidence suggests that the ancestor of the earliest hominins was a knuckle-walker and other evidence appears to contradict this possibility.

Knuckle-Walking and the Origin of Human Bipedalism

Functional anatomy and phylogeny together continue to suggest that humans are most likely to have evolved from a knuckle-walker, but a functionally plausible, though less parsimonious facultative bipedality hypothesis is also possible.

5 The Origins of Bipedal Locomotion

The final part of this chapter reviews why bipedalism was selected for and suggests an environmental shift would have involved strong selection for new behavioral strategies most likely linked to the efficient procurement of food.

Origin of human bipedalism: The knuckle-walking hypothesis revisited.

The functional significance of characteristics of the shoulder and arm, elbow, wrist, and hand shared by African apes and humans, including their fossil relatives, most strongly supports theknuckle-walking hypothesis, which reconstructs the ancestor as being adapted to knuckle- walking and arboreal climbing.

The arboreal origins of human bipedalism

The evidence is set out for the existence of a much earlier origin for bipedalism in a Miocene primate ancestor that was still predominantly tree-dwelling, and the notion that the common ancestor of great apes and humans was a knuckle-walking terrestrial species, as are gorillas and chimpanzees today is rejected.

Fossils, feet and the evolution of human bipedal locomotion

The varying interpretations based on this material are discussed and assessed in the context of new three‐dimensional morphometric analyses of australopithecine and Homo foot bones, suggesting that there may have been greater diversity in human bipedalism in the earlier phases of the authors' evolutionary history than previously suspected.

Origin of Bipedal Locomotion

Bipedalism is a highly specialized and unusual form of primate locomotion that is found today only in modern humans. The majority of extinct taxa within the Hominini were bipedal, but the degree to

The African ape-like foot of Ardipithecus ramidus and its implications for the origin of bipedalism

The ancestral condition from which humans evolved is critical for understanding the adaptive origin of bipedal locomotion. The 4.4 million-year-old hominin partial skeleton attributed to Ardipithecus

Why Do Knuckle‐Walking African Apes Knuckle‐Walk?

It is argued that knuckle‐walking was adopted by African apes as a means of ameliorating the consequences of repetitive impact loadings on the soft and hard tissues of the forelimb by employing isometric and/or eccentric contraction of antebrachial musculature during terrestrial locomotion.



Climbing, brachiation, and terrestrial quadrupedalism: historical precursors of hominid bipedalism.

  • D. Gebo
  • Biology
    American journal of physical anthropology
  • 1996
The vertical-climbing account of the evolution of locomotor behavior and morphology in hominid ancestry is reexamined in light of recent behavioral, anatomical, and paleontological findings and a

Knuckle‐walking and the evolution of hominoid hands

The knuckle-walking hands and plantigrade feet of African apes are both morphologically and adaptively distinct from those of Pongo, their nearest relative among extant apes, and these features are associated with a common adaptive shift to terrestrial locomotion and support placing chimpanzees and gorillas in the same genus Pan.

Forelimb mechanics as a function of substrate type during quadrupedalism in two anthropoid primates

The quantitative data presented here support previous models for the evolution of primate locomotion that were based on theoretical biomechanics and qualitative or anecdotal evidence and reveal several previously undocumented accommodations to "arboreal" quadrupedal locomotion in these two primates.

Quantitative and functional studies on the hands of the anthropoidea. I. The Hominoidea

The hands of the Hominoidea evidence four adaptive modes which distinguish the lesse apes (Hylobatidae), the orangutan (Pongo), the African apes (Pan), and man (Homo) from one another. The hands of

The locomotor anatomy of Australopithecus afarensis.

It is demonstrated that A. afarensis possessed anatomic characteristics that indicate a significant adaptation for movement in the trees, and it is speculated that earlier representatives of the A.Afarensis lineage will present not a combination of arboreal and bipedal traits, but rather the anatomy of a generalized ape.

Cladistic relationships of extant and fossil hominoids

Did knuckle walking evolve twice?

It is parsimonious to suggest that knuckle walking has evolved in parallel in the two lineages of chimpanzees and gorillas, according to morphological, behavioural and ecological data currently available.

Darwin's Apes, Dental Apes, and the Descent of Man: Normal Science in Evolutionary Anthropology

The 19th-century ape model and the burgeoning research provoked by it during the past century seem to satisfy Kuhn's criteria for the establishment of a normal science of evolutionary anthropology.

Origin of the human hand.

  • M. Marzke
  • Psychology, Biology
    American journal of physical anthropology
  • 1971
The presence of traits that are present in the apes and probably related to functions of the hand in suspension of the body, fist-walking, and knuckle-walking in man implies that human ancestors similarly used the hand to suspend the body in the trees and to support it on the back of the flexed fingers.

Hominid radius from the middle Pliocene of Lake Turkana, Kenya.

A nearly complete left radius, KNM-ER 20419, was recovered from middle Pliocene sediments east of Lake Turkana, Kenya in 1988 and is argued to be plesiomorphic for hominoids, supporting the argument that vertical climbing was an important locomotor behavior among both early hominoid and more immediate prebipedal ancestors.