Marciel et al. 2020 (Article) Aechmea

Differential geographical and ecological dynamics allow diversification of morphologically convergent giant bromeliads in the Atlantic Forest

Author(s):—J.R. Maciel, G. Zizka & M. Alves

Corresponding email:—jeffersonmaciel@recife.pe.gov.br

Publication:—Journal of Biogeography 1–14. (2020) — DOI

Abstract:—Aim: We investigate the evolutionary mechanisms that allow morphologically convergent lineages to share the same geographical space. We compared the evolutionary events that occurred along the diversification of Karawata and Aechmea subgen. Chevaliera in the Atlantic Forest by (a) verifying whether the climatic niches and habitats of Karawata and Chevaliera are similar; (b) testing whether the two groups had the same pattern of colonization in the Atlantic Forest; and (c) evaluating whether they had the same evolutionary dynamics of environmental space occupation.

Location: Brazilian Atlantic Forest

Taxon: Karawata and Aechmea subgen. Chevaliera (Bromeliaceae: Bromelioideae)

Methods: We explored differences in evolutionary dynamics between Karawata and Chevaliera by (a) analyzing their divergence times using Bayesian inference with a relaxed molecular clock; (b) estimating ancestral ranges and habitats with Dispersion Extinction Cladogenesis Lagrange and Statistical Dispersal Vicariance analyses; (c) testing climatic niche similarity, equivalency and overlap using principal component analysis; and, (d) evaluating shifts in speciation dynamics using Bayesian Analysis of Macroevolutionary Mixtures.

Results: Karawata and Chevaliera most likely originated in the Pliocene and diversified during the Pleistocene. The two clades originated in ombrophilous forests and shared a similar environmental space. However, Karawata and Chevaliera show different dynamics in the occupation of geographical and environmental spaces.

Main Conclusions: Our results suggest that the São Francisco and Jequitinhonha Rivers acted as geographical barriers for Karawata and Chevaliera. Differences in spatial and environmental evolutionary dynamics have allowed the two groups to occupy similar habitats as well as environmental and geographical spaces in the Brazilian Atlantic Forest.

Keywords:—Aechmea, biogeography, Bromeliaceae, Bromelioideae, evolution, neotropics