Siblings or Strangers? A Cranial and Dental Comparison between Alouatta seniculus and Ateles geoffroyi
Poster Number
26
Format
Poster Presentation
Faculty Mentor Name
Dorothy Dechant
Faculty Mentor Department
Dentistry
Abstract/Artist Statement
In this study, two closely related genera of New World monkeys, Alouatta seniculus (the Red Howler Monkey) and Ateles geoffroyi (the Black-Handed Spider Monkey) are analyzed. Literature searches were conducted to gather information on the diet, anatomy, habitat, behavior and locomotion of the two species. Two skulls, one of each species, were observed and measured for cranial and dental traits in order to address the possibility that features of the teeth and crania (form) reflect the contrasting dietary preferences and possible behavioral differences (function) in these two monkeys. In terms of diet, A. seniculus eats fruits and leaves in equal proportions while A. geoffroyi eats more fruits than any other foodstuffs. Measurement indices and photographs comparing the anatomical traits of the skull indicate conformity between the diet and the molar shape, cusp pattern and chewing muscle (masseter and temporalis) mass. The molars of A. seniculus show adaptations to a leaf-based diet, while those of A. geoffroyi show adaptations to a fruit-based diet, and the chewing muscles (masseter and temporalis) of A. seniculus are proportionately massive as compared to those of A. geoffroyi. Other unusual cranial features found in A. seniculus, such as foramen magnum posterior placement and small cranial capacity, are most likely consequences of locomotion style and behavioral adaptations to a unique howling style, respectively.
Location
DeRosa University Center, Ballroom
Start Date
20-4-2013 1:00 PM
End Date
20-4-2013 3:00 PM
Siblings or Strangers? A Cranial and Dental Comparison between Alouatta seniculus and Ateles geoffroyi
DeRosa University Center, Ballroom
In this study, two closely related genera of New World monkeys, Alouatta seniculus (the Red Howler Monkey) and Ateles geoffroyi (the Black-Handed Spider Monkey) are analyzed. Literature searches were conducted to gather information on the diet, anatomy, habitat, behavior and locomotion of the two species. Two skulls, one of each species, were observed and measured for cranial and dental traits in order to address the possibility that features of the teeth and crania (form) reflect the contrasting dietary preferences and possible behavioral differences (function) in these two monkeys. In terms of diet, A. seniculus eats fruits and leaves in equal proportions while A. geoffroyi eats more fruits than any other foodstuffs. Measurement indices and photographs comparing the anatomical traits of the skull indicate conformity between the diet and the molar shape, cusp pattern and chewing muscle (masseter and temporalis) mass. The molars of A. seniculus show adaptations to a leaf-based diet, while those of A. geoffroyi show adaptations to a fruit-based diet, and the chewing muscles (masseter and temporalis) of A. seniculus are proportionately massive as compared to those of A. geoffroyi. Other unusual cranial features found in A. seniculus, such as foramen magnum posterior placement and small cranial capacity, are most likely consequences of locomotion style and behavioral adaptations to a unique howling style, respectively.