¹Department of Biology, The Pennsylvania State University Altoona, PA, ²Department of Anatomy, Midwestern University Downers Grove, IL

Friday All day, Plaza Level

In summer 2006, we examined Maximum Ingested Bite Size (Vb), i.e., the largest piece of food that an animal will ingest whole without biting first, for three foods (carrot, melon and sweet potato) and seventeen species of strepsirrhines at the Duke Lemur Center. We found that frugivores consistently eat larger pieces of food than do folivores. This signal correlates with that seen in masticatory fiber architecture. Thus Vb appears to be an important link between behavior and anatomy – assuming that it remains consistent over time. To confirm the temporal stability of Vb, we repeated our experiments on a subset of the original individuals in summer 2011. Due to deaths and transfers, our repeated sample is small (six individuals, four species), but across all foods and animals, the average absolute difference is 10.16%. Given that the Vb values in this sample average <15mm on a side, this average percent difference is only slightly more than the precision of our cutting tools. The repeated samples are statistically indistinguishable (using a Related Samples Wilcoxon Sign Rank Test) for both carrot and sweet potato. However, the animals consumed slightly (though significantly) smaller pieces of melon in 2011. It is possible that the fruit used in 2011 were less ripe (more obdurate) than those of 2005, resulting in smaller bites. Thus we believe it is important to express Vb in terms of food mechanical properties measured during the study – a hypothesis tested in one of our other abstracts in this volume.