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Body size and digestive system shape resource selection by ungulates: A cross-taxa test of the forage maturation hypothesis

July 26, 2021

The forage maturation hypothesis (FMH) states that energy intake for ungulates is maximised when forage biomass is at intermediate levels. Nevertheless, metabolic allometry and different digestive systems suggest that resource selection should vary across ungulate species. By combining GPS relocations with remotely sensed data on forage characteristics and surface water, we quantified the effect of body size and digestive system in determining movements of 30 populations of hindgut fermenters (equids) and ruminants across biomes. Selection for intermediate forage biomass was negatively related to body size, regardless of digestive system. Selection for proximity to surface water was stronger for equids relative to ruminants, regardless of body size. To be more generalisable, we suggest that the FMH explicitly incorporate contingencies in body size and digestive system, with small-bodied ruminants selecting more strongly for potential energy intake, and hindgut fermenters selecting more strongly for surface water.

Citation Information

Publication Year 2021
Title Body size and digestive system shape resource selection by ungulates: A cross-taxa test of the forage maturation hypothesis
DOI 10.1111/ele.13848
Authors Saeideh Esmaeili, Brett R. Jesmer, Shannon E. Albeke, Ellen O. Aikens, Kathryn A. Schoenecker, Sarah R.B. King, Briana Abrahms, Bayarbaatar Buuveibaatar, Jeffrey L. Beck, Randall Boone, Francesca Cagnacci, Simon Chamaillé-Jammes, Buyanaa Chimeddorj, Paul Cross, Nandintsetseg Dejid, Jagdag Enkhbyar, Ilya Fischhoff, Adam T. Ford, Kate Jenks, Mahmoud-Reza Hemami, Jacob D. Hennig, Takehiko Y. Ito, Petra Kaczensky, Matthew Kauffman, John D. C. Linnell, Badamjav Lkhagvasuren, John F. McEvoy, Joerg Melzheimer, Jerod A. Merkle, Thomas Mueller, Jeff Muntifering, Atle Mysterud, Kirk A. Olson, Manuela Panzacchi, John Payne, Luca Pedrotti, Geir R. Rauset, Daniel I. Rubenstein, Hall Sawyer, John D. Scasta, Johannes Signer, Melissa Songer, Jared A. Stabach, Seth Stapleton, Olav Strand, Siva R. Sundaresan, Dorj Usukhjargal, Ganbold Uuganbayar, John Fryxell, Jacob R. Goheen
Publication Type Article
Publication Subtype Journal Article
Series Title Ecology Letters
Series Number
Index ID 70229346
Record Source USGS Publications Warehouse
USGS Organization Fort Collins Science Center