Worldwide decline of specialist species: toward a global functional homogenization?

  title={Worldwide decline of specialist species: toward a global functional homogenization?},
  author={J. Clavel and Romain Julliard and Vincent Devictor},
  journal={Frontiers in Ecology and the Environment},
Specialization is a concept based on a broad theoretical framework developed by evolutionary biologists and ecologists. In the past 10 years, numerous studies have reported that – in many contexts – generalist species are “replacing” specialist species. We review recent research on the concept of the ecological niche and species specialization, and conclude that (1) the observed worldwide decline in specialist species is predicted by niche theory, (2) specialist declines cause “functional… 

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