Niche conservatism promotes speciation in cycads: the case of Dioon merolae (Zamiaceae) in Mexico.
New Phytol
; 227(6): 1872-1884, 2020 09.
Article
em En
| MEDLINE
| ID: mdl-32392621
ABSTRACT
Niche conservatism is the tendency of lineages to retain the same niche as their ancestors. It constrains biological groups and prevents ecological divergence. However, theory predicts that niche conservatism can hinder gene flow, strengthen drift and increase local adaptation does it mean that it also can facilitate speciation? Why does this happen? We aim to answer these questions. We examined the variation of chloroplast DNA, genome-wide single nucleotide polymorphisms, morphological traits and environmental variables across the Dioon merolae cycad populations. We tested geographical structure, scenarios of demographic history, and niche conservatism between population groups. Lineage divergence is associated with the presence of a geographical barrier consisting of unsuitable habitats for cycads. There is a clear genetic and morphological distinction between the geographical groups, suggesting allopatric divergence. However, even in contrasting available environmental conditions, groups retain their ancestral niche, supporting niche conservatism. Niche conservatism is a process that can promote speciation. In D. merolae, lineage divergence occurred because unsuitable habitats represented a barrier against gene flow, incurring populations to experience isolated demographic histories and disparate environmental conditions. This study explains why cycads, despite their ancient lineage origin and biological stasis, have been able to diversify into modern ecosystems worldwide.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Zamiaceae
Tipo de estudo:
Prognostic_studies
País/Região como assunto:
Mexico
Idioma:
En
Revista:
New Phytol
Assunto da revista:
BOTANICA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Japão