Evolutionary ecology of Agave: distribution patterns, phylogeny, and coevolution (an homage to Howard S. Gentry)

Abstract

With more than 200 species, the genus Agave is one of the most interesting and complex groups of plants in the world, considering for instance its great diversity and adaptations. The adaptations include the production of a single, massive inflorescence (the largest among plants) where after growing for many years, sometimes more than 30, the rosette dies shortly afterward, and the remarkable coevolution with their main pollinators, nectarivorous bats, in particular of the genus Leptonycteris. The physiological adaptations of Agave species include a photosynthetic metabolism that allows efficient use of water and a large degree of succulence, helping to store water and resources for their massive flowering event. Ecologically, the agaves are keystone species on which numerous animal species depend for their subsistence due to the large amounts of pollen and nectar they produce, that support many pollinators, including bats, perching birds, hummingbirds, moths, and bees. Moreover, in many regions of Mexico and in the southwestern United States, agaves are dominant species. We describe the contributions of H. S. Gentry to the understanding of agaves and review recent advances on the study of the ecology and evolution of the genus. We analyze the present and inferred past distribution patterns of different species in the genus, describing differences in their climatic niche and adaptations to dry conditions. We interpret these patterns using molecular clock data and phylogenetic analyses and information of their coevolving pollinators and from phylogeographic, morphological, and ecological studies and discuss the prospects for their future conservation and management.

Diversidad de plantas vasculares de la Provincia Fisiográfica de la Sierra Madre Oriental, México.

“…Agave (22 especies) es un género considerado joven que se originó hace menos de 7 millones de años (Good-Avila et al 2006, Eguiarte et al 2021) derivado de una diversificación reciente por los cambios climáticos del pa sado y asociado a la alta heterogeneidad ambiental y climática. Su diversidad se ubica principalmente en los bosques templados y en matorrales xerófilos, casi siempre sobre lechos rocosos, cuyas poblaciones a menudo crecen en paredes de 90 ° de inclinación (Salinas-Rodríguez et al 2017).…”

“…Su diversidad se ubica principalmente en los bosques templados y en matorrales xerófilos, casi siempre sobre lechos rocosos, cuyas poblaciones a menudo crecen en paredes de 90 ° de inclinación (Salinas-Rodríguez et al 2017). El hecho de que sea uno de los géneros con más endemismos de la SMOr concuerda con los hallado por Eguiarte et al (2021) quienes reportan que la diversidad de agaves puede ser alta (más de 20 especies coexistiendo) en algunas áreas dentro de la provincia fisiográfica de la SMOr como porciones de San Luis Potosí y la Barranca de Metztitlán, en Hidalgo.…”

Genomic analyses of wild and cultivated bacanora agave (Agave angustifoliavar.pacifica) reveal inbreeding, few signs of cultivation history and shallow population structure

“…In this regard, species of Agave L. (Asparagaceae) may be an excellent model to investigate the relative importance of natural and/or anthropogenetic causes that affect population structure and diversity in plants. Agave is a species rich genus of perennial monocots found primarily in the arid regions of Mexico and the south-western United States [28,29].…”

“…In this regard, species of Agave L. (Asparagaceae) may be an excellent model to investigate the relative importance of natural and/or anthropogenetic causes that affect population structure and diversity in plants. Agave is a species rich genus of perennial monocots found primarily in the arid regions of Mexico and the south-western United States [28,29]. Agaves are keystone species that disproportionately affect their ecological community relative to their abundance by producing a large inflorescence with copious amounts of nectar and pollen [30-32].…”

Editorial: Recent Advances and Future Perspectives for Agavoideae Research: Agave, Yucca and Related Taxa

“…The interaction with other species seems to be very important in the evolutionary ecology of agavoid species, in particular mutualistic pollinator interactions (e.g., the Tegeticula moth in Yucca and the nectar feeding Leptonycteris bats in Agave; Pellmyr and Leebens-Mack, 1999 ; McKain et al, 2016 : Eguiarte et al, 2021 ). But microbes, including both fungi and bacteria, also seem to play very important roles in the biology of the Agavoideae.…”