Rensch’s Rule Crosses the Line: Convergent Allometry of Sexual Size Dimorphism in Hummingbirds and Flower Mites

  title={Rensch’s Rule Crosses the Line: Convergent Allometry of Sexual Size Dimorphism in Hummingbirds and Flower Mites},
  author={Robert K. Colwell},
  journal={The American Naturalist},
  pages={495 - 510}
Hummingbirds demonstrate the full scope of Rensch’s rule (females larger than males in small species, males larger than females in large species). The phoretic flower mites that hummingbirds compete with for nectar show the same pattern. An analysis of phylogenetically independent contrasts for 154 hummingbird and 37 mite species confirmed that both small (female‐larger) and large (male‐larger) species contribute to this result. I propose a common cause for this convergent pattern of sexual… 
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  • R. Shine
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    The Quarterly Review of Biology
  • 1989
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