IDEAS home Printed from
   My bibliography  Save this article

Load lightening and negotiation over offspring care in cooperative breeders


  • Rufus A. Johnstone


In cooperative breeders, parents that receive help with offspring care may either maintain their own effort or reduce it in compensation so that offspring gain little. Here, I build on an approach developed by McNamara et al. (McNamara, Gasson, and Houston 1999. Incorporating rules for responding into evolutionary games. Nature. 401: 368--371 and McNamara, Szekely, Webb, and Houston 2003. Should young ever be better off with one parent than with two? Behav Ecol. 14: 301--310.) to model behavioral negotiation over care in a cooperatively breeding species. I show that parental responsiveness to helper effort should vary with the shape of the parental cost function and that sex differences in the costs of care can give rise to sex differences in response to helpers. Such differences in responsiveness have major implications for the evolution of helping effort. When load lightening occurs, help may benefit mothers or fathers as much as offspring and to different degrees depending on the behavior of the 2. Consequently, when considering the influence of relatedness on helping effort, it is not only the relatedness of helpers to the young they assist that matters. Whether maternal or paternal kin help more, for instance, should reflect the relative degree of compensation by female and male parents. To understand helping, one must consider the whole pattern of relatedness among family members, as well as the ways in which they respond to one another. Copyright 2011, Oxford University Press.

Suggested Citation

  • Rufus A. Johnstone, 2011. "Load lightening and negotiation over offspring care in cooperative breeders," Behavioral Ecology, International Society for Behavioral Ecology, vol. 22(2), pages 436-444.
  • Handle: RePEc:oup:beheco:v:22:y:2011:i:2:p:436-444

    Download full text from publisher

    File URL:
    Download Restriction: Access to full text is restricted to subscribers.

    As the access to this document is restricted, you may want to search for a different version of it.


    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.

    Cited by:

    1. James L. Savage & Andrew F. Russell & Rufus A. Johnstone, 2013. "Maternal costs in offspring production affect investment rules in joint rearing," Behavioral Ecology, International Society for Behavioral Ecology, vol. 24(3), pages 750-758.
    2. Rufus A. Johnstone & Andrea Manica & Annette L. Fayet & Mary Caswell Stoddard & Miguel A. Rodriguez-Gironés & Camilla A. Hinde, 2014. "Reciprocity and conditional cooperation between great tit parents," Behavioral Ecology, International Society for Behavioral Ecology, vol. 25(1), pages 216-222.

    More about this item


    Access and download statistics


    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:oup:beheco:v:22:y:2011:i:2:p:436-444. See general information about how to correct material in RePEc.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Oxford University Press) or (Christopher F. Baum). General contact details of provider: .

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.