GARTNER, G.E.A.*; GREENE, H.W.; University of Miami, FL; Cornell University, Ithaca NY: Functional morphology and feeding ecology in the African snake genus, Dasypeltis

Distinctive morphological traits in organisms are often presumed to be adaptive. The six species of snake in the African genus, Dasypeltis, are all obligate egg eaters with a suite of morphological characters unique among snakes. These features include an enlarged harderian gland, multiple modifications of the skull, and enlarged, anteroventrally pointing vertebral hypapophyses. The morphology of Dasypeltis is presumed to be adaptive to the consumption and processing of eggs. A lack of empirical data, however, has failed to either refute or support this hypothesis. We measured the size of eggs ingested in both Dasypeltis and a facultative, generalist feeding snake, L. getula to get a qualitative assessment of any performance advantage in Dasypeltis. In addition, we explored the distribution of egg sizes in two regions to see if factors exist that could favor the selection of unique traits in Dasypeltis. Using laboratory-feeding trials, we studied the feeding ecology of Dasypeltis based upon the average mass of a meal and a qualitative measure of meals per year required for an individual snake. Mass ratios (.54) were significantly higher and meals per year were, on average, 60 percent less for Dasypeltis than for 18 other species of snake examined. The feeding performance and ecology of Dasypeltis is consistent with its unique morphology relative to the generalist feeding snake, L. getula.