title: Moa diet fits the bill: virtual reconstruction incorporating mummified remains and prediction of biomechanical performance in avian giants.
abstract: The moa (Dinornithiformes) are large to gigantic extinct terrestrial birds of New Zealand. Knowledge about niche partitioning, feeding mode and preference among moa species is limited, hampering palaeoecological reconstruction and evaluation of the impacts of their extinction on remnant native biota, or the viability of exotic species as proposed ecological 'surrogates'. Here we apply three-dimensional finite-element analysis to compare the biomechanical performance of skulls from five of the six moa genera, and two extant ratites, to predict the range of moa feeding behaviours relative to each other and to living relatives. Mechanical performance during biting was compared using simulations of the birds clipping twigs based on muscle reconstruction of mummified moa remains. Other simulated food acquisition strategies included lateral shaking, pullback and dorsoventral movement of the skull. We found evidence for limited overlap in biomechanical performance between the extant emu (Dromaius novaehollandiae) and extinct upland moa (Megalapteryx didinus) based on similarities in mandibular stress distribution in two loading cases, but overall our findings suggest that moa species exploited their habitats in different ways, relative to both each other and extant ratites. The broad range of feeding strategies used by moa, as inferred from interspecific differences in biomechanical performance of the skull, provides insight into mechanisms that facilitated high diversities of these avian herbivores in prehistoric New Zealand.
authors.affiliation: School of Environmental and Rural Science, Function, Evolution and Anatomy Research Laboratory, University of New England, Armidale, New South Wales 2351, Australia School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia mattard3@une.edu.au.
authors.forename: Marie R G
authors.initials: MR
authors.lastname: Attard
authors.affiliation: School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia.
authors.forename: Laura A B
authors.initials: LA
authors.lastname: Wilson
authors.affiliation: School of Biological Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia.
authors.forename: Trevor H
authors.initials: TH
authors.lastname: Worthy
authors.affiliation: Canterbury Museum, Rolleston Avenue, Christchurch 8013, New Zealand.
authors.forename: Paul
authors.initials: P
authors.lastname: Scofield
authors.affiliation: Department of Anatomy, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
authors.forename: Peter
authors.initials: P
authors.lastname: Johnston
authors.affiliation: Surgical and Orthopaedic Research Laboratories, Prince of Wales Clinical School, University of New South Wales, Randwick, New South Wales 2031, Australia.
authors.forename: William C H
authors.initials: WC
authors.lastname: Parr
authors.affiliation: School of Environmental and Rural Science, Function, Evolution and Anatomy Research Laboratory, University of New England, Armidale, New South Wales 2351, Australia.
authors.forename: Stephen
authors.initials: S
authors.lastname: Wroe
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D001717:Birds / Q000502:physiology*; D053476:Extinction, Biological; D005580:Fossils; D060434:Herbivory; D021621:Imaging, Three-Dimensional; D009520:New Zealand; D012886:Skull / Q000033:anatomy & histology / Q000502:physiology*; D013045:Species Specificity
keywords: biomechanics; dinornithiformes; finite-element analysis; moa; ratite