The influence of kinship on animal cooperation is often unclear. Cooperating Asiatic lion coalitions are linearly hierarchical; male partners appropriate resources disproportionately. To investigate how kinship affect coalitionary dynamics, we combined microsatellite based genetic inferences with long-term genealogical records to measure relatedness between coalition partners of free-ranging lions in Gir, India. Large coalitions had higher likelihood of having sibling partners, while pairs were primarily unrelated. Fitness computations incorporating genetic relatedness revealed that low-ranking males in large coalitions were typically related to the dominant males and had fitness indices higher than single males, contrary to the previous understanding of this system based on indices derived from behavioural metrics alone. This demonstrates the indirect benefits to (related) males in large coalitions. Dominant males were found to ‘lose less’ if they lost mating opportunities to related partners versus unrelated males. From observations on territorial conflicts we show that while unrelated males cooperate, kin-selected benefits are ultimately essential for the maintenance of large coalitions. Although large coalitions maximised fitness as a group, demographic parameters limited their prevalence by restricting kin availability. Such demographic and behavioural constraints condition two-male coalitions to be the most attainable compromise for Gir lions.
Bibliographical noteFunding Information:
We thank the Ministry of Environment Forests & Climate Change, India, Chief Wildlife Warden, Gujarat State and Chief Conservator of Forests, Junagadh for granting permissions and facilitation of the study. We thank the Director, Dean and Research Coordinator, Wildlife Institute of India for their support and encouragement. Sand-eep Kumar, Anshuman Sharma, Ram Ratan Nala, Dheeraj Mittal and Mohan Ram, Deputy Conservators of Forests, Gir are deeply acknowledged for facilitating field-work and data collection. We thank Bhawna Pant for her help with lab-work. We thank Mayank Kohli for his help with probability calculations in the supplementary note. We also thank Kausik Banerjee for sharing information on coalitions, and Keshab Gogoi for his help during fieldwork. We are indebted to our field assistants: Late Taj Mhd. Bloch, Osman Ali Mhd., Ismail Umar Siraj, Hamal Heptan, Hanif Pir Mhd., Mhd. Sameer and Iqbal Hamal Bloch for their hard-work and skill in working with lions. Without them this study would not have been possible. We also thank the wildlife guards and trackers of Gir Management Unit for their dedicated lion searches and information sharing. The work was supported by the Department of Science and Technology, India (Grant number: SERB/F/0601/2013-2016) and interim funds provided by the Wildlife Institute of India to the long-term project.
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't