The Endocrine System of the Squirrel Monkey

  • Christopher L. Coe
  • Erla R. Smith
  • Seymour Levine


In 1968, when the first treatise on the squirrel monkey appeared, it was already apparent that the physiology of New World monkeys differed from that of Old World primates, but few investigators were aware of the extensive differences in hormone metabolism and secretion (Rosenblum and Cooper, 1968). Since that time, it has become increasingly evident that the endocrine system of New World monkeys is extremely divergent from the general primate pattern in terms of both absolute hormone levels and the synthetic pathways utilized. We now know that most of the Callithricidae and smaller Cebidae have unusually high levels of adrenal and gonadal hormones, although typical values are difficult to describe because of the remarkable diversity in their reproductive physiology [for a species comparison, see Hearn (1983)]. In this chapter we will review a series of recent studies on the endocrine system of the squirrel monkey, which has some of the highest hormone levels observed so far. The level and magnitude of the hormone responses in the squirrel monkey have also provided a unique opportunity for assessing the influence of psychological and environmental variables, which may exert less overt effects in species with lower hormone levels. We will discuss the influence of seasonal and diurnal rhythms and the effect of genetic and maturational variables, and finally consider several of the important psychological processes that affect endocrine function.


Testosterone Level Squirrel Monkey World Monkey Mating Season Dominance Rank 
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Copyright information

© Springer Science+Business Media New York 1985

Authors and Affiliations

  • Christopher L. Coe
    • 1
  • Erla R. Smith
    • 2
  • Seymour Levine
    • 1
  1. 1.Department of Psychiatry and Behavioral SciencesStanford University School of MedicineStanfordUSA
  2. 2.Department of PhysiologyStanford University School of MedicineStanfordUSA

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