June 2022, plants — In this article, they examine the phylogenetic limits of Agave in the broad sense and present analyses elucidating the origin and rate of speciation in the group. These analyses lead to some new insights into the phylogenetic limits of Agave, indicate an estimated age of the family between 20 and 26 million years and an age of the Agave of ≤10 million years. Furthermore, they estimate a high mean per-lineage rate of diversification for the genus and find that rates of speciation were significantly elevated between 8 and 6 million years ago and then again between 3 and 2.5 million years ago. They then discuss the potential for both monocarpy and the evolution of a generalist pollination system, largely dependent on nectarivorous bat species, as possible driving factors in the radiation of the group.

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