Comparison of cranial performance between mainland and two island subspecies of the Arctic fox Vulpes lagopus (Carnivora: Canidae) during simulated biting

TY - JOUR

T1 - Comparison of cranial performance between mainland and two island subspecies of the Arctic fox Vulpes lagopus (Carnivora: Canidae) during simulated biting

AU - O'Higgins, Paul

AU - Fitton, Laura Catherine

AU - Proa, Antonio Miguel Guarita Pires Rosa

AU - Evteev, Andrej

AU - Nanova, Olga

N1 - © 2017 The Linnean Society of London, Biological Journal of the Linnean Society. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details.

PY - 2017/4/8

Y1 - 2017/4/8

N2 - Island subspecies of the Arctic fox Vulpes lagopus differ morphologically from the mainland subspecies. In particular, differences in cranial form may reflect varied biomechanical adaptations associated with hunting and feeding behaviours. We tested the hypothesis that the observed cranial differences between two island foxes (living on two North Pacific islands) and those living on the mainland have no impact on biomechanical performance during simulated biting. 3D cranial models of three Arctic fox subspecies were compared based on biomechanical parameters (e.g. local strain and large-scale deformation). Finite elements (FE) analyses were used to simulate equivalent biting loads, and geometric morphometrics was used to compare the modes of deformation among the models. The results showed differences in local strains and modes of global deformation among the three subspecies; the mainland subspecies was particularly distinct from the island subspecies. The representative cranium of the mainland subspecies experienced higher strain than that of both island subspecies during all bites. However, the findings highlight issues that arise when relating biomechanical performance, measured via FE analyses, to the foods consumed rather than to the mechanical properties of the individual’s diet. Additional physical properties data for each prey type are necessary to determine the extent to which the present findings reflect biomechanical adaptations to diet and prey acquisition.

AB - Island subspecies of the Arctic fox Vulpes lagopus differ morphologically from the mainland subspecies. In particular, differences in cranial form may reflect varied biomechanical adaptations associated with hunting and feeding behaviours. We tested the hypothesis that the observed cranial differences between two island foxes (living on two North Pacific islands) and those living on the mainland have no impact on biomechanical performance during simulated biting. 3D cranial models of three Arctic fox subspecies were compared based on biomechanical parameters (e.g. local strain and large-scale deformation). Finite elements (FE) analyses were used to simulate equivalent biting loads, and geometric morphometrics was used to compare the modes of deformation among the models. The results showed differences in local strains and modes of global deformation among the three subspecies; the mainland subspecies was particularly distinct from the island subspecies. The representative cranium of the mainland subspecies experienced higher strain than that of both island subspecies during all bites. However, the findings highlight issues that arise when relating biomechanical performance, measured via FE analyses, to the foods consumed rather than to the mechanical properties of the individual’s diet. Additional physical properties data for each prey type are necessary to determine the extent to which the present findings reflect biomechanical adaptations to diet and prey acquisition.

U2 - 10.1093/biolinnean/blx029

DO - 10.1093/biolinnean/blx029

M3 - Article

SN - 0024-4066

SP - 1

EP - 13

JO - Biological Journal of the Linnean Society

JF - Biological Journal of the Linnean Society

ER -