Assessing spatial patterns of phylogenetic diversity of Mexican mammals for biodiversity conservation

Abstract

Phylogenetic diversity is a biodiversity measurement that describes the amount of evolutionary history contained by the taxonomic units in a region. It has proven to be an important metric for determining conservation priorities. Mammalian phylogenetic diversity patterns have been suggested as potential surrogates of biodiversity for establishing priority areas for conservation. This study aims to identify areas of high mammalian phylogenetic diversity in Mexico, a megadiverse country with high mammalian richness, and to assess how well protected areas encompass the phylogenetic diversity. IUCN distribution data for 479 Mexican mammals were used to estimate species richness. Data for the molecular markers cytB, 12S and COI, was gathered from GenBank and from laboratory extractions for reconstructing a maximum-likelihood phylogenetic tree. Spatial patterns in phylogenetic diversity were estimated by summing the branch lengths of the phylogenetic tree representing species presence across grid cells. The results were compared with the distribution of protected areas in Mexico in order to assess if phylogenetic diversity is effectively conserved. The southeastern part of Mexico was found to be the most diverse. The breadth of the phylogenetic tree was well represented within the protected areas. Beta-diversity analyses showed that the species composition between protected and unprotected areas is very similar. Protected areas group based on the phylogenetic composition of mammal species into three clusters corresponding to the Nearctic, Neotropical, and Mexican Transition Zone biogeographical regions, which suggests that protected areas could be managed based on these clusters.