Trabecular structure of the elbow reveals divergence in knuckle-walking biomechanical strategies of African apes
African apes engage in a distinct form of locomotion called knuckle-walking, but there is much ambiguity as to when and how this locomotor behaviour evolved. This study aims to elucidate potential differences in knuckle-walking elbow posture and loading in African apes through the study of trabecula...
| Autores: | , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2021 |
| País: | España |
| Institución: | Universitat Autònoma de Barcelona |
| Repositorio: | Dipòsit Digital de Documents de la UAB |
| Idioma: | inglés |
| OAI Identifier: | oai:ddd.uab.cat:249696 |
| Acceso en línea: | https://ddd.uab.cat/record/249696 https://dx.doi.org/urn:doi:10.1111/evo.14354 |
| Access Level: | acceso abierto |
| Palabra clave: | Bone functional adaptation Joint posture Hominoid Locomotion Chimpanzee Gorilla |
| Sumario: | African apes engage in a distinct form of locomotion called knuckle-walking, but there is much ambiguity as to when and how this locomotor behaviour evolved. This study aims to elucidate potential differences in knuckle-walking elbow posture and loading in African apes through the study of trabecular bone. Using a whole-epiphysis approach, we quantified variation in trabecular structure of the distal humerus of chimpanzees, western lowland gorillas, and mountain gorillas in comparison to orang-utans, siamangs and a sample of Old and New World monkeys. Results demonstrate differences in the distribution of trabecular bone within the distal humerus that are consistent across taxa that habitually use a flexed-elbow posture in comparison to those that use an extended-elbow during locomotion. Western lowland gorillas show an extended-elbow pattern consistent with the straight forelimb position during knuckle-walking, whereas chimpanzees show a flexed-elbow pattern. Unexpectedly, mountain gorillas show an intermediate pattern between their western counterparts and chimpanzees. The differences found in elbow joint posture between chimpanzees and gorillas, and between gorilla species, point to diversification in the knuckle-walking biomechanical strategies among African apes, which has implications in the debate regarding the locomotor behaviour from which human bipedalism arose. |
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