Karyotypic diversity: a neglected trait to explain angiosperm diversification?

Evolutionary changes in karyotype provide genetic support to organisms' differentiation and adaptation; however, the association between karyotype diversity and species diversification in flowering plants (angiosperms) remains to be fully elucidated. We sought evidence for this association within a phylogenetic framework using a dataset comprising > 413,000 worldwide chromosome counts of 66,000 angiosperms species. Karyotypic diversity (e.g., number of distinct chromosome numbers) explains species richness and diversification rates at both family and genus levels highlighting that chromosome evolution has probably played, at least, an important role in reinforcing speciation that was already initiated or completed by other geographical or ecological drivers. Thus, research programs investigating chromosome variation as a direct or indirect driver of diversification should be encouraged.

Automated summary

This study used a global dataset of over 413,000 measured chromosome counts in plants to investigate the association between karyotypic diversity and species diversification in angiosperms. The results showed that karyotypic diversity explained species richness and diversification rates, suggesting that chromosome evolution plays an important role in speciation.