Androgen in free-living arctic ground squirrels: seasonal changes and influence of staged male-male aggressive encounters

@article{Buck2003AndrogenIF,
  title={Androgen in free-living arctic ground squirrels: seasonal changes and influence of staged male-male aggressive encounters},
  author={Charles Loren Buck and Brian M. Barnes},
  journal={Hormones and Behavior},
  year={2003},
  volume={43},
  pages={318-326}
}
  • C. Buck, B. Barnes
  • Published 1 February 2003
  • Environmental Science
  • Hormones and Behavior

Changing seasonality and phenological responses of free-living male arctic ground squirrels: the importance of sex

TLDR
The long-term phenology of hibernating male arctic ground squirrels living at two nearby sites in northern Alaska is investigated and it is suggested that the end of heterothermy in males is influenced by soil temperature and an endogenous circannual clock, but timing of male emergence from hibernation is affected by the timing of female emergence.

Plasma steroid hormones in two Arctic-breeding shorebirds: monogamy versus polygyny.

Testosterone predicts future dominance rank and mating activity among male chacma baboons

TLDR
The results support the challenge hypothesis with males exhibiting elevated testosterone in association with the acquisition of high rank (ensuring access to mates), rather than with mating itself, and testosterone levels predicted future, rather than current, mating activity.
...

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Seasonal changes in plasma glucocorticosteroids of free-living female yellow-pine chipmunks: effects of reproduction and capture and handling.

TLDR
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TLDR
The evidence suggests that the functions associated with the hypothalamic-pituitary-adrenal axis are compromised in breeding male Arctic ground squirrels, but not in red Squirrels, and it is proposed that in male red squirrels this axis has evolved in the context of a stable social system based on long-lived animals with individual territories which are needed to deal with unpredictable winter food supplies.