Evolution: how do characters evolve?

Andy Purvis

doi:10.1038/nature03092

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Evolution: how do characters evolve?

Andy Purvis

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Abstract

Ricklefs claims to show that morphological evolution in birds is associated with speciation events--that is, it is punctuational--by inference from data on only species number, clade age and character variance from a range of passerine clades. He suggests that variance increases in proportion with clade age under gradual change, but in proportion to the logarithm of species number if change is punctuational. Here I show that both clade age and the logarithm of species number independently predict variance under both gradual and punctuational change, rendering Ricklefs' results uninformative about his central hypothesis.

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Aging Animals Biodiversity Biological Evolution Genetic Variation Longevity Models, Biological Phylogeny Reproducibility of Results Research Design Songbirds Species Specificity Time Factors Comment Journal Article

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Andy Purvis. 2004-11-11. Evolution: how do characters evolve?. https://doi.org/10.1038/nature03092

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