A more precise speciation and extinction rate estimator

  title={A more precise speciation and extinction rate estimator},
  author={John Alroy},
  • J. Alroy
  • Published in Paleobiology 1 September 2015
  • Environmental Science
Abstract A new turnover rate metric is introduced that combines simplicity and precision. Like the related three-timer and gap-filler equations, it involves first identifying a cohort of taxa sampled in the time interval preceding the one of interest (call the intervals i0 and i1). Taxa sampled in i0 and i1 are two-timers (t2); those sampled in i0 and i2 but not i1 are part-timers (p); and taxa sampled only in either i1, i2, or i3 are newly notated here as either s1, s2, or s3. The gap-filler… 

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    Proceedings of the National Academy of Sciences
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