Sex and seasonal differences in aggression and steroid secretion in Lemur catta: Are socially dominant females hormonally ‘masculinized’?

@article{Drea2007SexAS,
  title={Sex and seasonal differences in aggression and steroid secretion in Lemur catta: Are socially dominant females hormonally ‘masculinized’?},
  author={Christine M. Drea},
  journal={Hormones and Behavior},
  year={2007},
  volume={51},
  pages={555-567}
}
  • C. Drea
  • Published 2007
  • Biology, Medicine
  • Hormones and Behavior
Female social dominance characterizes many strepsirrhine primates endemic to Madagascar, but currently there is no comprehensive explanation for how or why female lemurs routinely dominate males. Reconstructing the evolutionary pressures that may have shaped female dominance depends on better understanding the mechanism of inheritance, variation in trait expression, and correlating variables. Indeed, relative to males, many female lemurs also display delayed puberty, size monomorphism, and… Expand
Female rule in lemurs is ancestral and hormonally mediated
TLDR
It is suggested that relaxation of hormonally mediated FSD emerged only recently and that female masculinization may be the ancestral lemur condition, an idea that could revolutionize the understanding of the ancient socioecology and evolution of primate social systems. Expand
Endocrine correlates of pregnancy in the ring-tailed lemur (Lemur catta): Implications for the masculinization of daughters
  • C. Drea
  • Medicine, Biology
  • Hormones and Behavior
  • 2011
TLDR
Hormonal correlates of prenatal development were assessed to explore the possibility that maternal androgens may shape the masculine morphological and behavioral features of developing female lemurs and confirm that these steroids would reach the developing female and contribute to her masculinization. Expand
Endocrine Mediators of Masculinization in Female Mammals
Most mammal species show traditional patterns of sexual dimorphism (e.g., greater male size and aggression), the proximal mechanism of which involves the male's greater pre- and postnatal exposure toExpand
Endocrine Mediators of Masculinization in Female
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This review addresses the understanding of the mediating mechanisms of morpho logical and behavioral development in both traditional and exceptional mammal species, and the role for sex steroids in female development remains unclear. Expand
Relationships between steroid hormones in hair and social behaviour in ring-tailed lemurs (Lemur catta)
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It is concluded that being the recipient of aggression might be more stressful than being aggressive in ring-tailed lemurs, and that testosterone potentially mediates female dominance in this species. Expand
Exceptional endocrine profiles characterise the meerkat: sex, status, and reproductive patterns
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Female meerkats are strongly hormonally masculinised, possibly via A4’s bioavailability for conversion to T, and raised androgen concentrations may explain female aggressiveness in this species and give dominant breeders a heritable mechanism for their daughters’ competitive edge. Expand
Organizational and activational androgens, lemur social play, and the ontogeny of female dominance
TLDR
The importance of considering (1) missing data in behavioral endocrinology research, and (2) organizational androgens other than testosterone in studies of female dominance are discussed. Expand
Androgen and glucocorticoid levels reflect seasonally occurring social challenges in male redfronted lemurs (Eulemur fulvus rufus)
TLDR
No general rank-related pattern of testosterone or glucocorticoid excretion is found in male redfronted lemurs, and both hormones were excreted at significantly higher levels during the mating and the birth season, despite social stability during both periods. Expand
Seasonality, sociality, and reproduction: Long-term stressors of ring-tailed lemurs (Lemur catta)
TLDR
In the absence of nutritional stressors, social dominance was a relatively poor predictor of fGC in this female-dominant species, and the animals were maximally challenged by their social circumstances and reproductive events-males by competition for mating opportunities and females by late-term gestation and lactation. Expand
High maternal androstenedione levels during pregnancy in a small precocial mammal with female genital masculinisation
TLDR
It is proposed that female genital masculinisation might be a side effect of early exposure to elevated levels of maternal androgens that might be selected for to speed up precocial development. Expand
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