The unified neutral theory of biodiversity: do the numbers add up?

  title={The unified neutral theory of biodiversity: do the numbers add up?},
  author={Robert E. Ricklefs},
  volume={87 6},
  • R. Ricklefs
  • Published 1 June 2006
  • Environmental Science
  • Ecology
Hubbell's unified neutral theory is a zero-sum ecological drift model in which population sizes change at random in a process resembling genetic drift, eventually leading to extinction. Diversity is maintained within the community by speciation. Hubbell's model makes predictions about the distribution of species abundances within communities and the turnover of species from place to place (beta diversity). However, ecological drift cannot be tested adequately against these predictions without… 

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