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Abstract ObjectivesCortical bone geometry is commonly used to investigate biomechanical properties of primate mandibles. However, the ontogeny of these properties is less understood. Here we investigate changes in cortical bone cross‐sectional properties throughout capuchin ontogeny and compare captive versus wild, semi‐provisioned groups. Tufted capuchins (Sapajusspp.) are known to consume relatively hard/tough foods, while untufted capuchins (Cebusspp.) exploit less mechanically challenging foods. Previous research indicates dietary differences are present early in development and adultSapajusmandibles can resist higher bending/shear/torsional loads. Materials and methodsThis study utilized microCT scans of 22Cebusand 45Sapajusfrom early infancy to adulthood from three sample populations: one captiveCebus, one captiveSapajus, and one semi‐provisioned, free‐rangingSapajus. Mandibular cross‐sectional properties were calculated at the symphysis, P3, and M1. If the tooth had not erupted, its position within the crypt was used. A series of one‐way ANOVAs were performed to assess differences between and within the sample populations. ResultsMandible robusticity increases across ontogeny for all three sample populations.Sapajuswere better able to withstand bending and torsional loading even early in ontogeny, but no difference in shear resistance was found. Semi‐provisioned, free‐rangingSapajustend to show increased abilities to resist bending and torsional loading but not shear loading compared to captiveSapajus. DiscussionThis study helps advance our understanding of the primate masticatory system development and opens the door for further studies into adaptive plasticity in shaping the masticatory apparatus of capuchins and differences in captive versus free‐ranging sample populations.
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Seasonal drivers of faecal glucocorticoid metabolite concentrations in an African strepsirrhine primate, the thick-tailed greater galago ( Otolemur crassicaudatus )
Abstract As global non-human primate populations show dramatic declines due to climate change, land transformation and other anthropogenic stressors, it has become imperative to study physiological responses to environmental change in order to understand primate adaptability and enhance species conservation strategies. We examined the effects of seasonality on faecal glucocorticoid metabolite (fGCM) concentrations of free-ranging male and female thick-tailed greater galagos (Otolemur crassicaudatus) in an Afromontane habitat. To do so, we established an enzyme immunoassay (EIA) for monitoring fGCM concentrations in the species using a biological validation. Following this, faecal samples were collected each month over the course of a year from free-ranging males and females situated in the Soutpansberg Mountains, Limpopo, South Africa. Multivariate analyses revealed lactation period was a driver of fGCM levels, whereas sex and food availability mostly influenced seasonal fGCM concentrations in the total population. Thus far, the results of this study show that drivers of fGCM levels, an indication of increased adrenocortical activity, in O. crassicaudatus are numerous and complex within the natural environment. The species may be adapted to such conditions and an extreme change to any one component may result in elevated fGCM levels. This increases our understanding of strepsirrhine primate physiology and offers initial insights into species adaptability to a challenging environment.
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- Award ID(s):
- 1638833
- PAR ID:
- 10495526
- Editor(s):
- Cooke, Steven
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Conservation Physiology
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2051-1434
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/conphys/coab081
