Age-Related Changes in Dehydroepiandrosterone-Sulfate (DHEAS) in a Population of Wild Woolly Monkeys (Lagothrix lagothricha poeppigii)
Slideshow
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Participants
- Michael Bliss; Master’s Student, Kent State University, USA
- Noah Scruggs; Undergraduate Student, Miami University, USA
- Billy Browning; Undergraduate Student, Miami University, USA
- Nicholas Guetersloh; Undergraduate Student, Miami University, USA
- Kelsey Ellis; Assistant Professor, Miami University, USA
- Anthony Di Fiore; Professor, University of Texas, Austin, USA
- Andres Link; Professor, Universidad de los Andes, Bogotá, CO
- Emilee Hart; PhD Candidate, Kent State University, USA
- Evelyn Pain; Postdoctoral Associate, Boston University, USA
- Rafaela Takeshita; Associate Professor, Kent State University, USA
Summary
Dehydroepiandrosterone-sulfate (DHEAS) plays critical roles in physiological processes such as glucocorticoid antagonism and neurogenesis. It is the main product of adrenarche, a developmental stage linked to adrenal maturation. While hominids show a gradual increase in circulating DHEAS from childhood through early adulthood, most Cercopithecoidea primates display a brief early-life peak followed by decline. Our study investigated age-related DHEAS patterns in a wild population of woolly monkeys (Lagothrix lagothricha poeppigii) at Tiputini Biodiversity Station in Ecuador, a species with slow life-history traits similar to hominids, to explore whether adrenarche underlies convergent developmental and cognitive traits in Atelidae primates. Using noninvasive methods, this research provides insights into developmental endocrinology and establishes a framework for ethical monitoring of endangered populations.
Techniques
Fecal sample collection immediately post-defecation, hormone stabilization with ethanol and Sep-Pak C18 extraction, noninvasive behavioral monitoring to account for stress events, age and sex categorization via field observation and long-term monitoring records, enzyme-linked immunoassay (ELISA) for DHEAS quantification, RNAlater preservation for DNA analysis, fecal genotyping using microsatellite markers for individual identification, bioinformatics validation of genotypes.
Future Directions
Future work will collect longitudinal data with precise age measurements rather than categorical age classes to refine DHEAS trajectories. Additional analyses will integrate behavioral data to assess relationships between stress events and hormonal fluctuations. Expanding noninvasive genotyping and hormone monitoring across multiple Atelidae populations will deepen understanding of life-history evolution and inform conservation strategies.
Why This Matters
Noninvasive monitoring allows researchers to track stress, development, and overall health of endangered woolly monkeys without capturing or disturbing individuals. Understanding Atelidae evolution and potential convergence with human life-history traits not only provides insight into our own evolution but also strengthens conservation efforts. By highlighting behavioral and developmental similarities to humans, this research can shift public perception and promote protections for these endangered primates, emphasizing their unique biological and cognitive significance.
Figure 1. With age along the x-axis and DHEAS levels along the y-axis, this scheme (modified from Takeshita, unpublished) illustrates the age-related pattern of DHEAS secretion in the following primate groups: Cercopithecoids (marked with a grey dotted and dashed line), great apes (marked with a blue dashed line), and humans (marked with a solid orange line). The scheme demonstrates that Cercopithecoids do not undergo adrenarche, as their elevated DHEAS levels at birth (due to the fetal zone and rapid maturation of the ZR) decline steadily throughout life. In contrast, hominids experience a post-natal surge of DHEAS around 6-8 years of age, marking the onset of adrenarche. This gradually rise peaks at about 20-24 years of age and slowly declines thereafter.
