Evolutionary versatility of the avian neck

Marek, Ryan D, Falkingham, Peter L ORCID: 0000-0003-1856-8377, Benson, Roger BJ, Gardiner, James D ORCID: 0000-0003-1902-3416, Maddox, Thomas W and Bates, Karl T ORCID: 0000-0002-0048-141X (2021) Evolutionary versatility of the avian neck. PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES, 288 (1946). 20203150-.

This is the latest version of this item.

	Text MarekEtAl2021.pdf - Author Accepted Manuscript Download (1MB) \| Preview
	Text rspb.2020.3150.pdf - Published version Download (852kB) \| Preview

Official URL: http://dx.doi.org/10.1098/rspb.2020.3150

Abstract

Bird necks display unparalleled levels of morphological diversity compared to other vertebrates, yet it is unclear what factors have structured this variation. Using three-dimensional geometric morphometrics and multivariate statistics, we show that the avian cervical column is a hierarchical morpho-functional appendage, with varying magnitudes of ecologically driven osteological variation at different scales of organization. Contrary to expectations given the widely varying ecological functions of necks in different species, we find that regional modularity of the avian neck is highly conserved, with an overall structural blueprint that is significantly altered only by the most mechanically demanding ecological functions. Nevertheless, the morphologies of vertebrae within subregions of the neck show more prominent signals of adaptation to ecological pressures. We also find that both neck length allometry and the nature of neck elongation in birds are different from other vertebrates. In contrast with mammals, neck length scales isometrically with head mass and, contrary to previous work, we show that neck elongation in birds is achieved predominantly by increasing vertebral lengths rather than counts. Birds therefore possess a cervical spine that may be unique in its versatility among extant vertebrates, one that, since the origin of flight, has adapted to function as a surrogate forelimb in varied ecological niches.

Item Type:	Article
Uncontrolled Keywords:	axial skeleton, cervical column, evolution, Aves, ecological variation
Depositing User:	Symplectic Admin
Date Deposited:	03 Mar 2021 08:59
Last Modified:	18 Jan 2023 22:57
DOI:	10.1098/rspb.2020.3150
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3116437