Disentangling the mechanisms of mate choice in a captive koala population

School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
San Diego Zoo Global, San Diego, California, United States
DOI
10.7287/peerj.preprints.3487v1
Subject Areas
Animal Behavior, Conservation Biology
Keywords
Mate choice, captive breeding, genetic compatibility, Major Histocompatibility Complex (MHC), male heterozygosity, microsatellites
Copyright
© 2017 Brandies et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Brandies PA, Grueber CE, Ivy JA, Hogg CJ, Belov PK. 2017. Disentangling the mechanisms of mate choice in a captive koala population. PeerJ Preprints 5:e3487v1

Abstract

Successful captive breeding programs are crucial to the long-term survival of threatened species. However, pair incompatibility limits sustainability of many captive populations. Understanding whether the drivers of this incompatibility are behavioural or genetic, or a combination of both, is crucial to improving breeding programs. We used twenty-eight years of pairing data from the San Diego Zoo koala colony, plus genetic analyses using both MHC-linked and non-MHC-linked microsatellite markers, to show that both behavioural and genetic determinants can influence mating success. Male age was reconfirmed to be a contributing factor to the likelihood of a pair copulating. Familiarity was also reconfirmed to increase the probability of a successful copulation. Our data provided evidence that females select mates based on MHC and genome-wide similarity. Male heterozygosity at class II MHC loci influenced both pre- and post-copulatory female choice. Genome-wide similarity and similarity at the MHCII DAB locus were also found to influence female choice at the post-copulatory level. Finally, certain MHC-linked alleles were associated with increased or decreased mating success. We predict that utilising a variety of behavioural and MHC-dependent mate choice mechanisms improves female fitness through increased reproductive success. This study highlights the complexity of mate choice mechanisms within a species and the importance of ascertaining mate choice mechanisms to improve the success of captive breeding programs.

Author Comment

This is a submission to PeerJ for review.