Advertisement
Research Article

Winning the Genetic Lottery: Biasing Birth Sex Ratio Results in More Grandchildren

  • Collette M. Thogerson,

    Affiliation: Ecological Services, U.S. Fish & Wildlife Service, Arlington, Virginia, United States of America

    X
  • Colleen M. Brady,

    Affiliation: Department of Animal Sciences, Purdue University, West Lafayette, Indiana, United States of America

    X
  • Richard D. Howard,

    Affiliation: Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America

    X
  • Georgia J. Mason,

    Affiliation: Department of Animal and Poultry Science, University of Guelph, Ontario, Canada

    X
  • Edmond A. Pajor,

    Affiliation: Veterinary Medicine, University of Calgary, Alberta, Canada

    X
  • Greg A. Vicino,

    Affiliation: Collections Husbandry Science, San Diego Zoo Global, San Diego, California, United States of America

    X
  • Joseph P. Garner mail

    jgarner@stanford.edu

    Affiliation: Department of Comparative Medicine, and by Courtesy, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California, United States of America

    X
  • Published: July 10, 2013
  • DOI: 10.1371/journal.pone.0067867

Reader Comments (5)

Post a new comment on this article

Management effect sizes

Posted by clhowerton on 17 Jul 2013 at 21:29 GMT

I was curious what the effect sizes were for the various management techniques? Is it possible to parse out highly managed species (which I assume would be primates and endangered species)? If your claims are correct about false negatives (which I agree with by the way), understanding two issues: 1) do management techniques wash out the biological ability to adjust sex-ratios and 2) if different schemes (i.e. zoo consortiums, genetic testing, etc.) that affect the SR disproportionately, would go a long way to understand the underlying competition between human management and endogenous biological mechanisms.

No competing interests declared.

RE: Management effect sizes

jpgarner replied to clhowerton on 24 Jul 2013 at 01:10 GMT

These are all great comments. It's actually more the case that different groups of mammals have a tradition of being managed more or less intensively - which is why we used Order (and it's interactions) as one of our proxies for management. We also looked directly at the consequences of management (e.g. whether individuals got the opportunity to breed), as a controlling variables. The more of these controls we included the stronger the models became, but the basic effects are there even without these controls (which provides some indirect evidence that management may be adding noise to the data). With regards to your first and last questions - in upcoming papers we look at some of these individual life-history strategy aspects in much finer detail.

No competing interests declared.