Journal Article

Recently Formed Polyploid Plants Diversify at Lower Rates

Zhan, Shing H., Mayrose, Itay, Otto, Sarah P., Magnuson-Ford, Karen, Rieseberg, Loren H., Barker, Michael S., Rothfels, Carl J.

2011

Overview

The doubling of genomes does not cause increased plant speciation unless the progenitor lineages are highly fit. Polyploidy, the doubling of genomic content, is a widespread feature, especially among plants, yet its macroevolutionary impacts are contentious. Traditionally, polyploidy has been considered an evolutionary dead end, whereas recent genomic studies suggest that polyploidy has been a key driver of macroevolutionary success. We examined the consequences of polyploidy on the time scale of genera across a diverse set of vascular plants, encompassing hundreds of inferred polyploidization events. Likelihood-based analyses indicate that polyploids generally exhibit lower speciation rates and higher extinction rates than diploids, providing the first quantitative corroboration of the dead-end hypothesis. The increased speciation rates of diploids can, in part, be ascribed to their capacity to speciate via polyploidy. Only particularly fit lineages of polyploids may persist to enjoy longer-term evolutionary success.

• Publisher: American Association for the Advancement of Science,The American Association for the Advancement of Science
• Subject: Angiosperms / Biodiversity / Biological and medical sciences / Biological Evolution / BREVIA / Cytogenetics / Diploidy / Evolution / extinction / Extinction, Biological / Ferns - genetics / Flowers & plants / Fundamental and applied biological sciences. Psychology / Genetic Speciation / Genetics of eukaryotes. Biological and molecular evolution / Genome, Plant / genomics / Magnoliopsida - genetics / Ploidies / Polyploidy / Pteridophyta, spermatophyta / Speciation / vascular plants / Vegetals and fungi