miércoles, 30 de marzo de 2016

First phylogenetic analysis of Mesoamerican brocket deer Mazama pandora and Mazama temama (Cetartiodactyla: Cervidae) based on mitochondrial sequences: Implications for Neotropical deer evolution



Mammalian Biology 81 (2016) 303–313
First phylogenetic analysis of Mesoamerican brocket deer Mazama pandora and Mazama temama (Cetartiodactyla: Cervidae) based on mitochondrial sequences: Implications for Neotropical deer evolution
Luis A. Escobedo-Morales • Salvador Mandujano
Luis E. Eguiarte • Marco A. Rodríguez-Rodríguez
Jesús E. Maldonado

Abstract

Several recent studies have tried to unravel the complex evolutionary history of Neotropical cervids. However, the two Mesoamerican brocket deer Mazama pandora and M. temama have not been included in these studies and their relationship to other Neotropical cervids remains unclear. Here, we present analyses that included concatenated sequences from the mitochondrial genes ND2, Cytb, and tRNA-Pro-Control region.

Our results suggest that both Mesoamerican brocket deer fall within the “red” clade, more closely related to genus Odocoileus and red brocket deer species, such as South American Mazama americana, M. bororo, M. nana, and M. rufina.

We estimated that M. temama diverged from other red brocket deer ca. two MYA. Two hypothesis emerge regarding the relationship of the Yucatan brocket deer M. pandora with respect to the other Neotropical deer.
  • The first one, based on analyses of concatenated sequences from all three genes, implies an early split from a larger clade that includes Odocoileus and other red Mazama species, with an estimated divergence time dating back to 2.7 MYA. This would suggest isolation on the Yucatan peninsula, limiting the crossing of this species into South America.
  • The second one, based only on Cytb, places M. pandora more closely related to Odocoileus and with an estimated divergence time of ca. 1.9 MYA. This would suggest that the humid tropical forests of Mexico and Central America could have been the most likely place of origin of members of the red brocket deer clade.
Deer colonization into South America occurred after the complete formation of the Panamanian land bridge in the late Pliocene, more than one ancestor of the gray brocket deer clade crossed into South America, as well as a red brocket deer ancestor and Odocoileus dispersed southward. A posterior event probably occurred when divergent ancestors of M. temama and M. pandora respectively moved northward after the split with South American red brocket deer.

Our results add to the growing body of evidence calling for an extensive taxonomic revision of this group, and we concur with previous recommendations that the generic taxonomic designation of Mazama should be applied not only to the red brocket deer but also to all of the species currently recognized under the genus Odocoileus.

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