Temperature-related birth sex ratio bias in historical Sami: warm years bring more sons

@article{Helle2007TemperaturerelatedBS,
  title={Temperature-related birth sex ratio bias in historical Sami: warm years bring more sons},
  author={Samuli Helle and Samuli Helama and Jukka Jokela},
  journal={Biology Letters},
  year={2007},
  volume={4},
  pages={60 - 62}
}
The birth sex ratio of vertebrates with chromosomal sex determination has been shown to respond to environmental variability, such as temperature. However, in humans the few previous studies on environmental temperature and birth sex ratios have produced mixed results. We examined whether reconstructed annual mean temperatures were associated with annual offspring sex ratio at birth in the eighteenth to nineteenth century Sami from northern Finland. We found that warm years correlated with a… Expand
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