Prehensile Tail Use in Mantled Howler Monkeys (Alouatta palliata) and White-Faced Capuchin Monkeys (Cebus capucinus)

The prehensile tail, present in five platyrrhine genera, has evolved in parallel in Ateles, Lagothrix, Brachyteles, and Alouatta, comprising the atelines, and Cebus. While previous studies have examined the anatomical, morphological, and positional differences of prehensile tails, very few have examined how these tails are used, especially in a comparative study. How are prehensile tails used in both Cebus capucinus (White-Faced Capuchin Monkeys) and Alouatta palliata (Mantled Howler Monkeys), and do they serve similar ecological roles? Both species were studied at La Suerte Biological Field Station in Costa Rica utilizing the “one-zero” sampling technique according to a behavioral ethogram from July 2-July 11, 2015, collecting a total of 24.96 hours of data. A. palliata monkeys were found to utilize their prehensile tails more than C. capucinus during resting behaviors and C. capucinus monkeys utilized their prehensile tails more than A. palliata during traveling, which supports my predictions. C. capucinus utilized prehensile tails more during both foraging and feeding behaviors than A. palliata, which also supports my predictions. Although prior studies show varying results, based on my study, it seems that the prehensile tail serves as a mechanism for balance and maintaining stability during locomotion in larger-bodied A. palliata. The prehensile tail of C. capucinus also serves as a mechanism for maintaining balance during locomotion in an unstable canopy structure, especially during foraging and feeding in terminal branches.No embargoAcademic Major: Zoolog