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Moving in complex environments: a biomechanical analysis of locomotion on inclined and narrow substrates
Author(s) -
Christofer J. Clemente,
Taylor J. M. Dick,
Rebecca Wheatley,
Joshua Gaschk,
Ami Fadhillah Amir Abdul Nasir,
Skye F. Cameron,
Robbie S. Wilson
Publication year - 2019
Publication title -
journal of experimental biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.367
H-Index - 185
eISSN - 1477-9145
pISSN - 0022-0949
DOI - 10.1242/jeb.189654
Subject(s) - arboreal locomotion , marsupial , ecology , habitat , woodland , biology , riparian zone , population , demography , sociology
Characterisation of an organism's performance in different habitats provides insight into the conditions that allow it to survive and reproduce. In recent years, Northern quolls (Dasyurus hallucatus)—a medium-sized semi-arboreal marsupial native to northern Australia—have undergone significant population declines within open forest, woodland and riparian habitats, but less so in rocky areas. To help understand this decline, we quantified the biomechanical performance of wild Northern quolls as they ran up inclined narrow (13 mm pole) and inclined wide (90 mm platform) substrates. We predicted that quolls may possess biomechanical adaptations to increase stability on narrow surfaces, which are more common in rocky habitats. Our results display that quolls have some biomechanical characteristics consistent with a stability advantage on narrow surfaces. This includes the coupled use of limb pairs, as indicated via a decrease in footfall time, and an ability to produce corrective torques to counteract the toppling moments commonly encountered during gait on narrow surfaces. However, speed was constrained on narrow surfaces, and quolls did not adopt diagonal sequence gaits unlike true arboreal specialists such as primates. In comparison with key predators, such as cats and dogs, Northern quolls appear inferior in terrestrial environments but have a stability advantage at higher speeds on narrow supports. This may partially explain the heterogenous declines in Northern quoll populations among various habitats on mainland Australia.