Abstract
The vicuña (Vicugna vicugna) is the most representative wild ungulate of the high Andes of South America with two recognized morphological subspecies, V. v. mensalis in the north and V. v. vicugna in the south of its distribution. Current vicuña population size (460,000–520,000 animals) is the result of population recovery programs established in response to 500 years of overexploitation. Despite the vicuña’s ecosystemic, economic and social importance, studies about their genetic variation and history are limited and geographically restricted. Here, we present a comprehensive assessment of the genetic diversity of vicuña based on samples collected throughout its distribution range corresponding to eleven localities in Peru and five in Chile representing V. v. mensalis, plus four localities each in Argentina and Chile representing V. v. vicugna. Analysis of mitochondrial DNA and microsatellite markers show contrasting results regarding differentiation between the two vicuña types with mitochondrial haplotypes supporting subspecies differentiation, albeit with only a few mutational steps separating the two subspecies. In contrast, microsatellite markers show that vicuña genetic variation is best explained as an isolation by distance pattern where populations on opposite ends of the distribution present different allelic compositions, but the intermediate populations present a variety of alleles shared by both extreme forms. Demographic characterization of the species evidenced a simultaneous and strong reduction in the effective population size in all localities supporting the existence of a unique, large ancestral population (effective size ∼50,000 individuals) as recently as the mid-Holocene. Furthermore, the genetic variation observed across all localities is better explained by a model of gene flow interconnecting them rather than only by genetic drift. Consequently, we propose space “continuous” Management Units for vicuña as populations exhibit differentiation by distance and spatial autocorrelation linked to sex biased dispersal instead of population fragmentation or geographical barriers across the distribution.
Highlights
The vicuña (Vicugna vicugna) is the most representative wild ungulate of the Andean high plateau in South America (Franklin, 1983; Wheeler, 1995, 2012)
Estimates of genetic diversity excluding these loci were not significantly different from those estimated with all loci, we kept these markers for further analyses (Welch corrected t-test p-value > 0.05)
Results of the STRUCTURE analysis indicated that the best clustering solution was K = 2 based on the K method (Supplementary Figures 2A,B) with most of the samples from the Northern region being assigned to one cluster and most of the samples from the Southern region being assigned to the other cluster
Summary
The vicuña (Vicugna vicugna) is the most representative wild ungulate of the Andean high plateau in South America (Franklin, 1983; Wheeler, 1995, 2012). The greater length of the southern vicuña molar line supports phenotypic differentiation (Wheeler and Laker, 2009). During the 1980s Chile, Peru, and Bolivia donated vicuña to Ecuador which were introduced to Chimborazo National Park (1◦ 31 S, 78◦ 51 W) and currently represent a stable, growing population (Rodriìguez and MoralesDelanuez, 2017; Vicuña Convention, 2017).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
