1Inst. Population Genetics, University of Veterinary Medicine, Vienna, 2, Austrian Academy of Sciences, 3Dept. Anthropology, University of California, San Diego, 4Dept. Health and Environment, Austrian Institute of Technology
April 16, 2016 , Atrium Ballroom A/B
Lemur catta, the ring-tailed lemur, lives in highly seasonal environments, and, like some other lemurs, adheres to a schedule of strict seasonal reproduction and female dominance. We studied two troops in Tsimanampesotse National Park, southwestern Madagascar, in order to investigate patterns of diet and energetics with respect to lemur traits. We collected food plants and feces for chemical analyses (e.g., soluble carbohydrates, proteins) and urine samples for determining energy balance (assays for C-peptide and urea standardized with creatinine). Our study periods occurred over three seasons that coincided with different reproductive stages: the transition between wet and dry seasons (end lactation), beginning of the dry (end mating), and toward the end of the dry (end gestation).
C-peptide (proxy for glucose) levels were higher for females earlier in the dry season, while the opposite was the case for males. Urea (protein) levels were much higher for both sexes at the beginning of the dry season compared to the end. These results did not immediately correspond to availability of food resources as soluble carbohydrate and protein values in plant foods did not differ between seasons. However, actual intake (plant chemistry values factored by amount ingested) was much higher earlier in the dry season.
Females appear to incur more stress than males energetically throughout the dry season, while males appear to be in negative energy balance earlier, directly following mating efforts. These energetic patterns align with reproductive efforts, which underscore that sex differences in energetics need to be considered in discussions of lemur traits.
Funded by Austrian Academy of Sciences.