Searching for Dental Signals of Exudativory in Galagos

  • Anne M. Burrows
  • Leanne T. Nash
Part of the Developments in Primatology: Progress and Prospects book series (DIPR)


Consumption of exudates requires acquiring exudates. Exudate-feeding marmosets possess a distinct dental signal consisting of the “short-tusked” anterior dentition, which they use to gouge tree bark and elicit exudate flow. Observations of exudate-feeding galagos have indicated that these animals use the toothcomb in some fashion to acquire exudates, but behavioral observations of galago exudate acquisition are incomplete. The present study was designed to assess dental morphometrics of galagos in an effort to search for a more complete dental signal of exudate-feeding in this group. Cleaned and dried skulls from 137 galago specimens were selected representing seven species with varying proportions of exudates in their diets. Two-dimensional measurements were taken from the toothcomb, maxillary canine, mandibular and maxillary first premolars, and the last mandibular molar. Surface areas of these teeth were calculated except for the molar and a biomechanical shape variable to estimate the resistance ability of the toothcomb to bending loads was created. Analyses of variance on residuals of the plots of dental dimensions against a measure of body size indicated that relative toothcomb height and the ability to resist bending loads were significantly greater in exudate-feeding galagos relative to galagos that do not consume exudates. Additionally, the other teeth emerged as being significantly different among galagos, depending on the amount of exudates consumed. While the toothcomb may be used in some exudate acquisition fashion in galagos, it is clear that other teeth, especially in combination, may provide a dental signal to exudate feeding in galagos.


Great Surface Area Maxillary Canine Wide Tooth Dietary Niche Dietary Category 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors would like to express their deep gratitude to Gary Schwartz for handling the review process of this chapter and his generous advice on statistical methodology. We thank Valerie DeLeon, Betsy Dumont, Bob Martin, and Tim Smith, for comments on various drafts of this chapter, and we especially thank Chris Vinyard for his assistance with creating the shape variable formula for the toothcomb. We also thank John Wible and Sue McLaren (Carnegie Museum of Natural History), Lyman Jellema (Cleveland Museum of Natural History), Bill Stanley (Field Museum of Natural History), and Chris Conroy (Museum of Vertebrate Zoology) for access to specimens.


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© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Department of Physical TherapyDuquesne UniversityPittsburghUSA
  2. 2.Department of AnthropologyUniversity of PittsburghPittsburghUSA

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