Patterns of morphological and ecological similarities of small-eared shrews (Soricidae, Cryptotis) in tropical montane cloud forests from Mesoamerica
Por:
Guevara, Lazaro, Sanchez-Cordero, Victor
Publicada:
1 ene 2018
Resumen:
It has been proposed that high morphological similarity between closely
related species of small-eared shrews resulted from a recent divergence
and intermittent population connectivity, presumably due to Pleistocene
climatic fluctuations and associated changes in forest habitat
distribution. Here we examined the morphological variation of two sister
species of small-eared shrews inhabiting cloud forests from Mexico,
Cryptotis obscurus and C. mexicanus. We then used ecological niche
modelling to provide compelling evidence for current environmental
barriers for population connectivity, and for detecting divergent
ecological niches between candidate species. Our results indicated that
the species boundaries in this clade should be subject to change. High
morphological similarity suggested that populations of C. obscurus and
C. mexicanus located west of the Isthmus of Tehuantepec, a major
geographic barrier for montane species, are conspecific. Niche
divergence between these two putative species was not supported
indicating niche conservatism across the evolutionary history of these
small-eared shrews. In addition, several barriers seem to play a main
role for current lineage divergence between populations within this
clade. The population located east of the Isthmus, previously referred
to C. mexicanus, might prove to represent a new species based on
morphological distinction and current geographic isolation. We have
highlighted that estimating species' potential distributions provides
insights to evaluating the effect of geographic barriers on lineage
divergence and making stronger inferences when delimiting species.
Filiaciones:
Guevara, Lazaro:
Univ Nacl Autonoma Mexico, Inst Biol, Dept Zool, Apartado Postal 70-153, Ciudad De Mexico 04510, Mexico
Univ Nacl Autonoma Mexico, Fac Ciencias, Dept Biol Evolut, Ciudad De Mexico 04510, Mexico
Sanchez-Cordero, Victor:
Univ Nacl Autonoma Mexico, Inst Biol, Dept Zool, Apartado Postal 70-153, Ciudad De Mexico 04510, Mexico
|