Population Structure of mtDNA Variation due to Pleistocene Fluctuations in the South American Maned Wolf (Chrysocyon brachyurus, Illiger, 1815): Management Units for Conservation

Abstract

The maned wolf (Chrysocyon brachyurus) is one of the largest South American canids, and conservation across this charismatic carnivore's large range is presently hampered by a lack of knowledge about possible natural subdivisions which could influence the population's viability. To elucidate the phylogeographic patterns and demographic history of the species, we used 2 mtDNA markers (D-loop and cytochrome b) from 87 individuals collected throughout their range, in Argentina, Bolivia, Brazil, and Uruguay. We found moderate levels of haplotype and nucleotide diversity, and the 14 D-loop haplotypes were closely related. Genetic structure results revealed 4 groups, and when coupled with model inferences from a coalescent analysis, suggested that maned wolves have undergone demographic fluctuations due to changes in climate and habitat during the Pleistocene glaciation period approximately 24000 years before present (YBP). This genetic signature points to an event that occurred within the timing estimated for the start of the contraction of the Cerrado around 50000 YBP. Our results reveal a genetic signature of population size expansion followed by contraction during Pleistocene interglaciations, which had similar impacts on other South American mammals. The 4 groups should for now be considered management units, within which future monitoring efforts should be conducted independently.

Maned wolves retain moderate levels of genetic diversity and gene flow despite drastic habitat fragmentation

“…In the present study, we aimed to evaluate the current patterns of genetic structure in maned wolf wild populations by including samples from wild animals throughout the species range with a suite of 12 polymorphic microsatellite loci. We compared our results with those obtained in a previous study based on mtDNA (González et al 2015a). We also analyzed samples from captive maned wolves to compare them to the wild population.…”

“…Twelve microsatellite loci, originally designed for domestic dog, were selected on the basis of polymorphism level, reliable amplification and easy scorability in several canid species (Franco Berriel 2004, Smith et al 2006, Salim et al 2007, Fontoura-Rodrigues et al 2008, Lion et al 2011, Do Passo Ramalho et al 2014. Based on annealing temperature, fragment size and fluorochrome label, we designed 4 PCR multiplexes.…”

“…A recent study looking at maned wolf phylogeographic patterns based solely on mtDNA (Gonzá -lez et al 2015a) found moderate levels of haplotype and nu cleotide diversity, and genetic structure was partitioned into 4 groups. This suggested that maned wolves underwent demographic fluctuations due to changes in climate and habitat during the Pleistocene glaciation period approximately 24 000 yr before present (BP) (González et al 2015a). However, the authors were unable to make definitive conservation management recommendations because they lacked evidence from nuclear markers, and they recommended that future genetic studies should focus on increasing the number of individuals and populations sampled with additional variable nuclear markers.…”

“…However, the authors were unable to make definitive conservation management recommendations because they lacked evidence from nuclear markers, and they recommended that future genetic studies should focus on increasing the number of individuals and populations sampled with additional variable nuclear markers. Because González et al (2015a) based their study on single-locus evidence from maternally inherited mtDNA, it was not possible to assess whether members of the different mitochondrial genetic lineages interbreed with each other. Microsatellite markers are among the markers of choice to study finescale variation in endangered species populations.…”

A large historical refugium explains spatial patterns of genetic diversity in a Neotropical savanna tree species

“…Collevatti et al, 2003Collevatti et al, , 2013bRamos et al, 2007;Novaes et al, 2010Novaes et al, , 2013, as well as animals (e.g. Prado et al, 2012;Santos et al, 2014;Gonzalez et al, 2015). The few studies on phylogeography and demographic history performed with Cerrado plant species have shown some congruencies.…”