Social resilience and stress reactivity in chacma baboons

  • Zina Morbach

Student thesis: Doctoral Thesis

Abstract

Resilience describes an individual’s ability to “rebound” after experiencing adversity and can be studied using the ‘three-hit concept’, where genetic factors (hit-1) interact with the early-life environment (hit-2), with the resulting phenotype’s resilience depending on later-in-life environment (hit-3). I investigated resilience and stress reactivity in a group of wild chacma baboons in South Africa, by exploring the different steps involved in the process of resilience: (i) describing physiological stress response measures and their link to life-history stage, climate, and predation; (ii) investigating coping behaviours and sociability and their link to physiological stress response measures; and (iii) developing non-invasive measures of resilience (based on the difference between individuals’ observed and predicted coat condition given their stress reactivity) and exploring links between resilience and coping behaviours and sociability.


Mean faecal glucocorticoid metabolite (fGCM) levels differed between lifehistory stages, and females, but not males, showed increased fGCM levels in response to predation. Furthermore, baboons of both sexes used displacement behaviours as coping behaviour in response to adversity, and rates of giving grooming in males, and rates of being aggressive in females, were linked to physiological stress response measures in the longer term. Females appeared to benefit from having strong social bonds as these were linked to lower mean fGCM levels, reflecting social buffering, while social integration was linked to lower stress reactivity in both sexes. Finally, resilience differed with life-history stages in females, but not males, and was linked to reproductive success in females. In both sexes, resilience might be behaviourally mediated, as high rates of displacement behaviours were associated with higher resilience, and in females, social integration was also linked to higher resilience. This study contributes conceptually and methodologically by developing non-invasive measures of resilience, thus enabling further investigation of resilience in the context of inter-individual differences in fitness in wild animals.
Date of Award9 Jul 2020
Original languageEnglish
Awarding Institution
  • University of Roehampton
Sponsors Roehampton VC Scholarship & Gesellschaft für Primatologie e.V
SupervisorStuart Semple (Director of Studies) & Ann MacLarnon (Co-Supervisor)

Keywords

  • Chacma baboons
  • Resilience
  • Stress reactivity
  • Social behaviour
  • Social buffering
  • Coping behaviour
  • Social network analysis
  • Stress

Cite this

Social resilience and stress reactivity in chacma baboons
Morbach, Z. (Author). 9 Jul 2020

Student thesis: Doctoral Thesis