Genetic demography at the leading edge of the distribution of a rabies virus vector

Abstract

The common vampire bat, Desmodus rotundus, ranges from South America into northern Mexico in North America. This sanguivorous species of bat feeds primarily on medium to large‐sized mammals and is known to rely on livestock as primary prey. Each year, there are hotspot areas of D. rotundus‐specific rabies virus outbreaks that lead to the deaths of livestock and economic losses. Based on incidental captures in our study area, which is an area of high cattle mortality from D. rotundus transmitted rabies, it appears that D. rotundus are being caught regularly in areas and elevations where they previously were thought to be uncommon. Our goal was to investigate demographic processes and genetic diversity at the north eastern edge of the range of D. rotundus in Mexico. We generated control region sequences (441 bp) and 12‐locus microsatellite genotypes for 602 individuals of D. rotundus. These data were analyzed using network analyses, Bayesian clustering approaches, and standard population genetic statistical analyses. Our results demonstrate panmixia across our sampling area with low genetic diversity, low population differentiation, loss of intermediate frequency alleles at microsatellite loci, and very low mtDNA haplotype diversity with all haplotypes being very closely related. Our study also revealed strong signals of population expansion. These results follow predictions from the leading‐edge model of expanding populations and supports conclusions from another study that climate change may allow this species to find suitable habitat within the U.S. border.

The ecology of chronic wasting disease in wildlife

“…Infectious diseases are not distributed randomly across landscapes (Peterson, ; Escobar & Craft, ). Models accounting for landscape or climate configuration to quantify environmental conditions where spread of diseases occurs are used to understand distributional disequilibrium in the spread of diseases (Benavides, Valderrama & Streicker, ; Hutter et al ., ; Piaggio et al ., ), like CWD, that are undergoing range expansions. Interestingly, the available studies conducted at landscape levels also suggest that CWD does not occur randomly across taxonomic, temporal, geographic, and environmental spaces (Mathiason et al ., ) (Fig.…”

Invasion genetics of the silver carp (Hypophthalmichthys molitrix) across North America: Differentiation of fronts, introgression, and eDNA detection

“…The leading edge hypothesis was supported by a single-nucleotide polymorphism (SNP) analysis of three invasive fronts for the bank vole Myodes glareolus introductions in Ireland, which showed reduced genetic diversity, but no accumulation of deleterious alleles, and possible selection for traits involved in immunity and behavior [104]. Low diversity at the leading edge was implicated in a study of variation in North American expansion areas for the vampire bat Desmodus rotundus [21]. When invasive species spread via jump dispersal, new population areas often possess reduced genetic diversity, as was seen with invasive dreissenid mussels spreading from the Great Lakes to smaller lakes to the west [15, 16] and with the European green crab’s Carcinus maenas spread from the eastern to western coasts of North America [105].…”

“…Populations at the expansion fronts of an invasion front frequently possess less genetic variability than those at the core of the invasion, which is termed the “leading edge” hypothesis [20, 21]. The phenotypes of individuals at these front populations are postulated to be adapted for dispersal and high reproductive output [22], where they experience low population density, and may benefit from greater resource availability and less intraspecific competition, enhancing reproductive success [23, 24].…”

Vampire bat reservoir and main transmitter of rabies, a public health problem in Mexico

“…8 That is the case of the vampire bat Desmodus rotundus that has adapted to different climates, heights and ecosystems that few decades ago where considered as natural barriers. 10 Attacks from vampire bat Desmodus rotundus to farm animals are more and more frequent, even in regions where, for decades, have been considered disease free zones. 10,11 This problem is getting worse, because farm animals favor the population growth and geographic distribution of this chiropter because they are their main food source.…”