Sexual dimorphism and distorted sex ratios in spiders

@article{Vollrath1992SexualDA,
  title={Sexual dimorphism and distorted sex ratios in spiders},
  author={Fritz Vollrath and Geoffrey Alan Parker},
  journal={Nature},
  year={1992},
  volume={360},
  pages={156-159}
}
SEXUAL dimorphism in body size is widespread in the animal kingdom. Whereas male giantism has been studied and explained extensively1,2, male dwarfism has not. Yet it is neither rare3–7 nor without theoretical interest8,9. Here we provide experimental and comparative data on spiders to support the theory that dwarf males are associated with high differential adult mortality, with males at much greater risk. Species with sedentary (low-risk) females have dwarf, roving (high-risk) males. Life… 

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