Unpredictable Evolution in a 30-Year Study of Darwin's Finches

@article{Grant2002UnpredictableEI,
  title={Unpredictable Evolution in a 30-Year Study of Darwin's Finches},
  author={P. Grant and B. R. Grant},
  journal={Science},
  year={2002},
  volume={296},
  pages={707 - 711}
}
Evolution can be predicted in the short term from a knowledge of selection and inheritance. However, in the long term evolution is unpredictable because environments, which determine the directions and magnitudes of selection coefficients, fluctuate unpredictably. These two features of evolution, the predictable and unpredictable, are demonstrated in a study of two populations of Darwin's finches on the Galápagos island of Daphne Major. From 1972 to 2001,Geospiza fortis (medium ground finch… Expand
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  • Biology, Medicine
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  • 2008
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TLDR
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Reproductive isolation of sympatric morphs in a population of Darwin's finches
TLDR
It is demonstrated that the two morphs show strong positive assortative pairing, a pattern that holds over three breeding seasons and during both dry and wet conditions, and provides strong support for the central role of ecology during the early stages of adaptive radiation. Expand
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