Jennifer K. Hellmann

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This study explores how muscle and liver energy stores are linked with social status and the social environment in Neolamprologus pulcher, a cooperatively breeding fish that lives in colonies comprised of up to 200 distinct social groups. Subordinate muscle energy stores were positively correlated with the number of neighbouring social groups in the colony,(More)
In this paper, we argue that, contra Strevens (2013), understanding in the sciences is sometimes partially constituted by the possession of abilities; hence, it is not (in such cases) exhausted by the understander's bearing a particular psychological or epistemic relationship to some set of structured propositions. Specifically, the case will be made that(More)
1 Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH, USA 2 Aquatic Behavioural Ecology Laboratory, Department of Psychology, Neuroscience, and Behaviour, McMaster University, Hamilton, ON, Canada 3 Department of Environmental Science and Policy, Duke University, Durham, NC, USA 4 Department of Mathematics, The(More)
The degree to which group members share reproduction is dictated by both within-group (e.g. group size and composition) and between-group(e.g. density and position of neighbours) characteristics. While many studies have investigated reproductive patterns within social groups, few have simultaneously explored how within-group and between-group social(More)
a Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH, U.S.A. b Aquatic Behavioural Ecology Lab, Department of Psychology, Neuroscience, and Behaviour, McMaster University, Hamilton, ON, Canada c Department of Environmental Science & Policy, Duke University, Durham, NC, U.S.A. d Department of Mathematics, The(More)
In group-living species, the degree of relatedness among group members often governs the extent of reproductive sharing, cooperation and conflict within a group. Kinship among group members can be shaped by the presence and location of neighbouring groups, as these provide dispersal or mating opportunities that can dilute kinship among current group(More)
http://dx.doi.org/10.1016/j.anbehav.2015.06.001 0003-3472/© 2015 The Association for the Study of A Contests over resources are a key facet of social behaviour and have received extensive theoretical attention. However, the assumptions and predictions of the theoretical models have rarely been tested experimentally in wild free-living vertebrates. Here, we(More)
Members of social groups must defend their shared territory against both predators and competitors. However, individuals differ widely in their contributions to territorial defence. Assessing the variation in response to territorial intrusions provides insight into both the benefits and costs of group living for different group members. In this study, we(More)
The social brain hypothesis posits that frequent social interactions, characteristic of group living species, select for greater socio-cognitive abilities and the requisite neural machinery. An extension of the social brains hypothesis, known as the cooperative breeding brain hypothesis, postulates that cooperatively breeding species, which live in stable(More)
In complex animal societies, direct interactions between group members can influence the behavior and glucocorticoid levels of individuals involved. Recently, it has become apparent that third-party group members can influence dyadic interactions, and vice versa. Thus, glucocorticoid levels may vary depending on interactions of other members of the social(More)