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Genetic imprints of Brosimum alicastrum Sw. in Mexico
Author(s) -
LópezBarrera Gabriela,
OchoaZavala Maried,
Quesada Mauricio,
Harvey Nick,
NúñezFarfán Juan,
GonzálezRodríguez Antonio,
RochaRamírez Víctor,
Oyama Ken
Publication year - 2021
Publication title -
american journal of botany
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.218
H-Index - 151
eISSN - 1537-2197
pISSN - 0002-9122
DOI - 10.1002/ajb2.1725
Subject(s) - biology , biological dispersal , genetic diversity , gene flow , geographical distance , genetic structure , isolation by distance , population , evolutionary biology , genetic variation , ecology , gene , genetics , demography , sociology
Abstract Premise The mechanisms generating the geographical distributions of genetic diversity are a central theme in evolutionary biology. The amount of genetic diversity and its distribution are controlled by several factors, including dispersal abilities, physical barriers, and environmental and climatic changes. We investigated the patterns of genetic diversity and differentiation among populations of the widespread species Brosimum alicastrum in Mexico. Methods Using nuclear DNA microsatellite data, we tested whether the genetic structure of B. alicastrum was associated with the roles of the Trans‐Mexican Volcanic Belt and the Isthmus of Tehuantepec as geographical barriers to gene flow and to infer the role of past events in the genetic diversity patterns. We further used a maximum‐likelihood population‐effects mixed model (MLPE) to identify the main factor affecting population differentiation in B. alicastrum . Results Our results suggested that Mexican B. alicastrum is well differentiated into three main lineages. Patterns of the genetic structure at a finer scale did not fully correspond to the current geographical barriers to gene flow. According to the MLPE mixed model, isolation by distance is the best model for explaining the genetic differentiation of B. alicastrum in Mexico. Conclusions We propose that the differentiation patterns might reflect (1) an ancient differentiation that occurred in Central and South America, (2) the effects of past climatic changes, and (3) the functions of some physical barriers to gene flow. This study provides insights into the possible mechanisms underlying the geographic genetic variation of B. alicastrum along a moisture gradient in tropical lowland forests.