The 84th Annual Meeting of the American Association of Physical Anthropologists (2015)

A comprehensive phylogenetic study of cranial morphology in Southeast Asian mammals


1Committee on Evolutionary Biology, University of Chicago, 2Department of Anthropology, The Field Museum, 3Department of Anthropology, University of Illinois at Urbana-Champaign

March 28, 2015 , Gateway Ballroom 2/3/4/5 Add to calendar

According to the island rule, there is a general evolutionary trend for large-bodied mammals to undergo reduction in body size on islands (especially small ones) because food resources are severely limited. Here, we present data for both volumetric measurements and 3D morphometric cranial landmark dimensions related to body size to document the evolution of mammalian cranial morphology on islands. Taking a dataset for three large-bodied taxa from Southeast Asia, including 125 individuals from 11 gibbon species (family Hylobatidae), 64 individual longtailed macaques (Macaca fascicularis), and 32 individuals from six pig species (family Suidae), we found that a large percentage of total variance in all three taxa is explained by size. This indicates that larger individuals have relatively more robust mandibles and cranial area for muscle attachments. However, it is important to take intraspecific phylogenetics into account when analyzing such geometric morphometric data because there are apparent differences in within-species variation on different islands. We have successfully sequenced mitogenomes from 50-150 year old museum specimens using the Illumina platform to build intraspecific phylogenies for a comprehensive phylogenetic study of cranial morphometric data in the taxa investigated.