Estimating times of extinction in the fossil record

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Estimating times of extinction in the fossil record.

Because the fossil record is incomplete, the last fossil of a taxon is a biased estimate of its true time of extinction. Numerous methods have been developed in the palaeontology literature for estimating the true time of extinction using ages of fossil specimens. These methods, which typically give a confidence interval for estimating the true time of extinction, differ in the assumptions they...

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Many ecological and palaeontological studies focus on extinction. The fossil record is particularly important for studying long-term patterns in extinction: although analyses of extant phylogenies can estimate extinction rates (e.g. Alfaro et al. 2009) and even suggest mass extinctions (e.g. Crisp & Cook 2009), they cannot imply trilobites ever existed or that sphenodonts (now represented only ...

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Using data drawn from large-scale databases, a number of interesting trends in the fossil record have been observed in recent years. These include the average decline in extinction rates throughout the Phanerozoic, the average increase in standing diversity, correlations between rates of origination and extinction, and simple laws governing the form of survivorship curves and the distribution o...

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The discipline-wide effort to database the fossil record at the occurrence level has made it possible to estimate marine invertebrate extinction and origination rates with much greater accuracy. The new data show that two biotic mechanisms have hastened recoveries from mass extinctions and confined diversity to a relatively narrow range over the past 500 million years (Myr). First, a drop in di...

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ژورنال

عنوان ژورنال: Biology Letters

سال: 2016

ISSN: 1744-9561,1744-957X

DOI: 10.1098/rsbl.2015.0989