Autor(es)

Griffin, Benjamin W. ; Martin-Silverstone, Elizabeth ; Pegas, Rodrigo V. ; Meilak, Erik Anthony ; Costa, Fabiana R. ; Palmer, Colin ; Rayfield, Emily J.

• Tipo de documento: Artigo Científico
• Fonte: PeerJ; v. 12, p. 25-pg., 2024-08-05.

Resumo

Take-off is a vital part of powered flight which likely constrains the size of birds, yet extinct pterosaurs are known to have reached far larger sizes. Three different hypothesised take-off motions (bipedal burst launching, bipedal countermotion launching, and quadrupedal launching) have been proposed as explanations for how pterosaurs became airborne and circumvented this proposed morphological limit. We have constructed a computational musculoskeletal model of a 5 m wingspan ornithocheiraean pterosaur, reconstructing thirty-four key muscles to estimate the muscle moment arms throughout the three hypothesised take-off motions. Range of motion constrained hypothetical kinematic sequences for bipedal and quadrupedal take-off motions were modelled after extant flying vertebrates. Across our simulations we did not find higher hindlimb moment arms for bipedal take-off motions or noticeably higher forelimb moment arms in the forelimb for quadrupedal take-off motions. Despite this, in all our models we found the muscles utilised in the quadrupedal take-off have the largest total launch applicable moment arms throughout the entire take-off sequences and for the take-off pose. This indicates the potential availability of higher leverage for a quadrupedal take-off than hypothesised bipedal motions in pterosaurs pending further examination of muscle forces. (AU)

• Processo FAPESP: 19/10231-6 - Biomecânica da postura da asa em voo de Anhanguera piscator e Tupuxuara leonardii (Pterosauria: Pterodactyloidea) e considerações acerca da evolução do voo no grupo
• Beneficiário: Rodrigo Vargas Pêgas
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 22/03099-7 - Modelagem tridimensional e biomecânica do movimento em vertebrados extintos
• Beneficiário: Fabiana Rodrigues Costa Nunes
• Modalidade de apoio: Auxílio à Pesquisa - Projeto Inicial
• Processo FAPESP: 23/11296-0 - Biomecânica da musculatura mandibular e hábitos alimentares em Pterosauria
• Beneficiário: Rodrigo Vargas Pêgas
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado