Assessing sociality: catarrhine microsatellites and the dynamics of glucocorticoids with social relationships in wild male Assamese macaques (Macaca assamensis)
Dissertation
Datum der mündl. Prüfung:2024-01-30
Erschienen:2024-02-22
Betreuer:Prof. Dr. Julia Ostner
Gutachter:Prof. Dr. Julia Ostner
Gutachter:PD Dr. Christian Roos
Gutachter:Prof. Dr. Julia Fischer
Gutachter:Prof. Dr. Nivedita Mani
Gutachter:Dr. Dietmar Zinner
Gutachter:Dr. Verena Behringer
Dateien
Name:Thesis_JS_no_CV.pdf
Size:7.32Mb
Format:PDF
Zusammenfassung
Englisch
In order to navigate within-group competition and maximise fitness, strategies have evolved in group-living animals, including social dominance ranks and affiliative relationships. Both of these play a crucial role in shaping an individual’s long-term fitness. The association between dominance rank and fitness benefits has been long established in males, with higher ranked individuals showing improved fitness outcomes compared to their subordinates, such as through improved access to mating opportunities. Similarly, recent work has highlighted that strong, equitable, and stable affiliative relationships or social bonds can confer fitness benefits, including increased longevity or a pathway to improved rank position. To assess the long-term fitness consequences of sociality, the genetic variation of a population needs to be accurately quantified. Microsatellites, short repetitive DNA sequences found in non-coding regions of the genome, are a common marker for doing so in wild species due to their cross-species amplifiability, high heterozygosity, and compatibility with low-quality, non-invasive DNA samples. However, issues such as undetected allele variation, null alleles, or allelic dropout remain. Microsatellite data is also often not comparable between labs due to the use different loci or genotyping methods, hindering cross-species comparisons and collaborative work. I addressed these methodological issues and describe a refined panel of 42 microsatellites for catarrhine primates; developed from an extensive literature review of published catarrhine microsatellites, in combination with a genotype-by-sequencing (GBS) pipeline. The extent to which the fitness outcomes of dominance ranks and affiliative relationships are also associated with more immediate costs can be investigated by quantifying the underlying hormonal responses. Dynamics in sociality can induce costs through affecting glucocorticoids (GCs), a key mediator of homeostasis, and an indicator of the physiological response to challenges and within-group competition. I studied the correlated glucocorticoid responses to dynamics in dominance rank and affiliation in wild male Assamese macaques, using over 4,100 faecal samples from 62 adult males, spanning 15 years at Phu Khieo Wildlife Sanctuary, Thailand.
Keywords: sociality; macaque; primate; social relationships; glucocorticoids; microsatellites; genetic methods