Dataset Information

The relationship between cranial structure, biomechanical performance and ecological diversity in varanoid lizards.

ABSTRACT: Skull structure is intimately associated with feeding ability in vertebrates, both in terms of specific performance measures and general ecological characteristics. This study quantitatively assessed variation in the shape of the cranium and mandible in varanoid lizards, and its relationship to structural performance (von Mises strain) and interspecific differences in feeding ecology. Geometric morphometric and linear morphometric analyses were used to evaluate morphological differences, and finite element analysis was used to quantify variation in structural performance (strain during simulated biting, shaking and pulling). This data was then integrated with ecological classes compiled from relevant scientific literature on each species in order to establish structure-function relationships. Finite element modelling results showed that variation in cranial morphology resulted in large differences in the magnitudes and locations of strain in biting, shaking and pulling load cases. Gracile species such as Varanus salvadorii displayed high strain levels during shaking, especially in the areas between the orbits. All models exhibit less strain during pull back loading compared to shake loading, even though a larger force was applied (pull =30N, shake = 20N). Relationships were identified between the morphology, performance, and ecology. Species that did not feed on hard prey clustered in the gracile region of cranial morphospace and exhibited significantly higher levels of strain during biting (P = 0.0106). Species that fed on large prey clustered in the elongate area of mandible morphospace. This relationship differs from those that have been identified in other taxonomic groups such as crocodiles and mammals. This difference may be due to a combination of the open 'space-frame' structure of the varanoid lizard skull, and the 'pull back' behaviour that some species use for processing large prey.

SUBMITTER: McCurry MR

PROVIDER: S-EPMC4479569 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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The relationship between cranial structure, biomechanical performance and ecological diversity in varanoid lizards.

McCurry Matthew R MR Mahony Michael M Clausen Phillip D PD Quayle Michelle R MR Walmsley Christopher W CW Jessop Tim S TS Wroe Stephen S Richards Heather H McHenry Colin R CR

PloS one 20150624 6

Skull structure is intimately associated with feeding ability in vertebrates, both in terms of specific performance measures and general ecological characteristics. This study quantitatively assessed variation in the shape of the cranium and mandible in varanoid lizards, and its relationship to structural performance (von Mises strain) and interspecific differences in feeding ecology. Geometric morphometric and linear morphometric analyses were used to evaluate morphological differences, and fin ...[more]

PMID: 26106889

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Dataset Information

The relationship between cranial structure, biomechanical performance and ecological diversity in varanoid lizards.

Publications

The relationship between cranial structure, biomechanical performance and ecological diversity in varanoid lizards.

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