EVOLUTION OF HINDLIMB POSTURE IN ARCHOSAURS: LIMB STRESSES IN EXTINCT VERTEBRATES

@article{Kubo2007EVOLUTIONOH,
  title={EVOLUTION OF HINDLIMB POSTURE IN ARCHOSAURS: LIMB STRESSES IN EXTINCT VERTEBRATES},
  author={Tai Kubo and Michael J. Benton},
  journal={Palaeontology},
  year={2007},
  volume={50}
}
  • T. Kubo, M. Benton
  • Published 1 November 2007
  • Geography, Biology, Environmental Science
  • Palaeontology
Abstract:  During the Triassic, some 250–200 million years ago, the basal archosaurs showed a transition from sprawling to erect posture. Past studies focused on changes in bone morphology, especially on the joints, as they reorientated from a sprawling to an erect posture. Here we introduce a biomechanical model to estimate the magnitude of femur stress in different postures, in order to determine the most reasonable postures for five basal archosaurs along the line to crocodiliforms (the… 
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References

SHOWING 1-10 OF 42 REFERENCES
Evolution of hindlimb posture in nonmammalian therapsids: biomechanical tests of paleontological hypotheses
  • R. Blob
  • Biology, Geography
    Paleobiology
  • 2001
TLDR
A biomechanical model is derived to test the hypothesis that the use of multiple postures was ancestral to the more upright posture typical of most mammals, and indicates that the axial rotation of the femur typical in sprawling locomotion can reduce peak bending stresses.
In vivo locomotor strain in the hindlimb bones of alligator mississippiensis and iguana iguana: implications for the evolution of limb bone safety factor and non-sprawling limb posture
  • Blob, Biewener
  • Biology
    The Journal of experimental biology
  • 1999
TLDR
Measurements of in vivo locomotor strain from the limb bones of lizard and crocodilian species, animals from previously unsampled phylogenetic lineages with non-parasagittal limb posture and kinematics suggest that, in some lineages, strain magnitudes may not have been maintained at constant levels through the evolution of a non-sprawling posture.
The hind limb step cycle of Caiman sclerops and the mechanics of the crocodile tarsus and metatarsus
Crocodiles use two distinct hind limb step cycles: an erect pattern seen in the high walk and a more sprawling lizard-like pattern. These differ in the amount of abduction of the femur and rotation
Basal Archosaurs: Phylogenetic Relationships and Functional Implications
TLDR
Erect posture has been identified as the key adaptation (possibly associated with locomotor stamina) that resulted in the archosaurian radiation.
HINDLIMB KINEMATICS DURING TERRESTRIAL LOCOMOTION IN A SALAMANDER (DICAMPTODON TENEBROSUS)
  • Ashley-Ross
  • Biology
    The Journal of experimental biology
  • 1994
A quantitative study of hindlimb kinematics during terrestrial locomotion in a non-specialized salamander was undertaken to allow comparisons with limb movements in other groups of tetrapods. Five
Interspecific scaling of the hindlimb skeleton in lizards, crocodilians, felids and canids: does limb bone shape correlate with limb posture?
  • R. Blob
  • Biology, Environmental Science
  • 2000
During locomotion, lizards and crocodilians generally use a more sprawling limb posture than most mammals and experience substantial axial rotation of the femur. Consequently, the limb bones of most
Limb posture and locomotion in the Virginia opossum (Didelphis marsupialis) and in other non‐cursorial mammals
TLDR
Walking movements in eight mammalian species were studied cineradiographically with particular attention given to limb posture and excursion relative to the parasagittal and horizontal planes.
Locomotion in rauisuchid thecodonts
ABSTRACT The systematic approach to the Rauisuchidae suggests that the lowest level of locomotor organization of the Thecodontia is represented by the Proterosuchidae, which can be regarded as
Biomechanics and kinematics of limb-based locomotion in lizards: review, synthesis and prospectus.
  • A. Russell, V. Bels
  • Biology, Engineering
    Comparative biochemistry and physiology. Part A, Molecular & integrative physiology
  • 2001
Wing bone stresses in free flying bats and the evolution of skeletal design for flight
TLDR
The data demonstrate that torsion and shear are unique and crucial features of skeletal biomechanics during flight, and suggest that the evolution of skeletal design in bats and other flying vertebrates may be driven by the need to resist these loads.
...
...