DWARFISM IN INSULAR SLOTHS: BIOGEOGRAPHY, SELECTION, AND EVOLUTIONARY RATE

@article{Anderson2002DWARFISMII,
  title={DWARFISM IN INSULAR SLOTHS: BIOGEOGRAPHY, SELECTION, AND EVOLUTIONARY RATE},
  author={Robert P. Anderson and Charles O. Handley},
  journal={Evolution},
  year={2002},
  volume={56}
}
Abstract The islands of Bocas del Toro, Panama, were sequentially separated from the adjacent mainland by rising sea levels during the past 10,000 years. Three‐toed sloths (Bradypus) from five islands are smaller than their mainland counterparts, and the insular populations themselves vary in mean body size. We first examine relationships between body size and physical characteristics of the islands, testing hypotheses regarding optimal body size, evolutionary equilibria, and the presence of… 
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The results indicate that morphological divergence occurs along with high levels of environmental overlap; perhaps historical biogeographic factors along with sexual selection may have promoted its diversification.
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