The 89th Annual Meeting of the American Association of Physical Anthropologists (2020)

Bites and chews in two sympatric lemur species in southwestern Madagascar


1Institute of Population Genetics, University of Veterinary Medicine, Vienna, 2Austrian Academy of Sciences

April 18, 2020 , Platinum Ballroom Add to calendar

Jaw form has been related to loads incurred during feeding, which are determined by oral processing behaviors. In this study, we examine how foods that differ in geometry and mechanical properties affect biting and chewing in two lemur species that are sympatric in the dry forest site of Beza Mahafaly special reserve in southwestern Madagascar.

We conducted all-day focal animal follows of Lemur catta (Lc) and Propithecus verreauxi (Pv) in the dry season months of May-July. During observations, we took detailed data on feeding behaviors including pre-oral processing, ingestion location, and food intake. Foods were later collected and tested for toughness and elastic modulus in a field laboratory. Bites and chews were quantified from videos shot concurrently with observations. For this analysis, we focused on two foods that were eaten by both species, tamarind (kily) fruit and mamyaho leaves.

Lc and Pv spends 33% and 0.88% of total feeding time, respectively, on old kily fruit and 19% and 2% on mamyaholeaves. Preliminary analysis shows differences in ingestive behaviors for both species. Lc, on average, has higher chew numbers than Pv when consuming leaves, but the opposite pattern occurs for kily fruit. While bite numbers and chewing rates are similar across all categories, biting rates differ by food. Pv takes longer to feed on kily based on average sequence time. Our results show that bites and chews vary by lemur species and by food type, suggesting differences in processing related to overall food properties.

Funded by the Austrian Science Fund (FWF)

Slides/Poster (pdf)