Kessous et al. 2024b (Article) evolution

New insights into the classification, diversification, and evolutionary dynamics of bromeliads

Author(s):—I.M. Kessous, H. Farooq, W. Testo, M.F.T. Jiménez, B. Neves, A.R. Pinto, F. Salgueiro, A.F. Costa & C.D. Bacon

Publication:—Botanical Journal of the Linnean Society online: boae074. (2024) — DOI

Abstract:—The Neotropics have been host to a myriad of geological and climatic events that have shaped the biodiversity present in the region. Bromeliaceae forms one of the most prominent components of the Neotropical flora, being considered the largest group nearly exclusive to the Americas, with almost 4000 species divided into eight subfamilies. Here, we utilize a new time-calibrated molecular phylogeny including 1268 bromeliad taxa and integrate habitat and morphological data to answer the following questions: (i) Are bromeliad subfamilies monophyletic, and did Neogene and Quaternary events in South America coincide with their divergence? (ii) Did naked seeds of berry-fruited species, epiphytic growth, and climatic factors increase bromeliad diversification? Our analysis reconstructed a new topology concerning some recently diverged lineages, with the genus Bromelia emerging as the sister group of a clade including all remaining Bromelioideae lineages + Puyoideae. Miocene events possibly triggered the diversification of bromeliads after a long period of stasis during the Palaeogene. We hypothesize that the morphological shift between Bromelia and Bromelioideae (except Bromelia) is related to the colonization of a new high-elevation environment by Puyoideae in the Andes. Additionally, our results show that naked seeds and the epiphytic growth form positively influence diversification rate, while precipitation, temperature, and elevation have a negative influence. We emphasize the importance of considering a variety of morphological and ecological features to enhance our understanding of bromeliad evolution.

Keywords:—epiphytes; evolution; monocots; Neotropics; pineapple