Disease outbreaks select for mate choice and coat color in wolves

Abstract

We know much about pathogen evolution and the emergence of new disease strains, but less about host resistance and how it is signaled to other individuals and subsequently maintained. The cline in frequency of black-coated wolves ( Canis lupus ) across North America is hypothesized to result from a relationship with canine distemper virus (CDV) outbreaks. We tested this hypothesis using cross-sectional data from wolf populations across North America that vary in the prevalence of CDV and the allele that makes coats black, longitudinal data from Yellowstone National Park, and modeling. We found that the frequency of CDV outbreaks generates fluctuating selection that results in heterozygote advantage that in turn affects the frequency of the black allele, optimal mating behavior, and black wolf cline across the continent.

Possible origins and implications of atypical morphologies and domestication-like traits in wild golden jackals (Canis aureus)

“…All these findings might support this second scenario of multiple de-novo mutations, which after their occurrence and their random independent inheritance in the course of mating between carrier individuals would not confer a single anomalous phenotypic trait, but rather, through pleiotropic effects, multiple features, such as those observed in the atypical animals of the study area. However, the preliminary molecular analyses conducted in this study do not allow us to confirm or reject such a hypothesis since, despite the 3-bp melanistic deletion at the CBD103 gene, no other genes likely related to coat colouration and morphology have been exhaustively typed 52 . Therefore, future genome-wide studies could be conducted to analyse the Golan Heights canids using specific targeted DNA capture arrays 57 ad hoc designed for candidate morphology and coat colour genes potentially under positive selection, thus identifying possible islands of adaptive variation and environmentally driven functional variants related to local adaptation.…”

“…These findings suggest that the particular morphology of Jackie might be due to ancient introgressions of domestic dog alleles, that were almost completely eroded after a few backcrossing generations, leaving traces of dog ancestry only at particular genomic regions or in linkage with multiple or particular coat colour and other morphologically associated genes, and thus not detectable at the few uniparental and autosomal loci we analysed. Future genome-wide studies, based on ancestral chromosomal block reconstruction methods 49 , 50 could help identify possible dog-derived regions along Jackie's genome, potentially the reason for the observed morphological anomalies, as previously conducted in North American grey wolves to detect a functional 3-bp melanistic deletion along chromosome 16, presumably introgressed via historical admixture with dogs 51 , 52 , or in North American bison ( Bison bison ) populations to identify cattle haplotypes introgressed in their genomes over the last 200 years 53 .…”

“…However, it is currently known that multiple genes are simultaneously involved in canine morphology and coat colour patterns 39 – 41 and their combined effects on the expressed phenotype and colouration can also determine direct or indirect adaptive advantages in different ecological contexts. In fact, a number of selection studies have highlighted latitudinal camouflage advantages in densely forested areas or a functional resistance to pathogen infections in North American and European black canids carrying the 3-bp deletion at the β-Defensin gene 52 , 54 – 56 , as well as positive selection and increased fitness rates in arctic habitats for lighter coloured Greenland and Tibetan wolves 39 . The de-novo mutations potentially responsible for the lighter and white spotted coat colours observed in Jackie and in the other four Golan Heights jackals might have randomly originated in a single individual and then been transmitted to the subsequent generations by circulating among a few related animals, potentially conferring onto them an adaptive advantage in a Mediterranean semi-desert with sparse arboreal vegetation.…”

A standard protocol to report discrete stage-structured demographic information

“…These new methods produce models whose structure does not fit into the frameworks for reporting that seemed so comprehensive in the past. Furthermore, the body of data available for demography has grown rapidly from long-term ecological research and monitoring networks (e.g., LTERs in USA (Hobbie, Carpenter, Grimm, Gosz, & Seastedt, 2003), Wytham Woods (Macdonald, Newman, Stewart, Domingo-Roura, & Johnson, 2002;Simmonds, Cole, Sheldon, & Coulson, 2020)) and remote sensing approaches (e.g., tagging, dronemonitoring projects (Cubaynes et al, 2022)). These datasets, and recent advances in MPM theory and methods, enable researchers to link population dynamics and demography to environmental conditions and multiple individual traits (e.g., sex and age (Childs, Sheldon, & Rees, 2016); age and kinship (Caswell, 2019b(Caswell, , 2020) rather than a single trait.…”

“…, LTERs in USA (Hobbie, Carpenter, Grimm, Gosz, & Seastedt, 2003), Wytham Woods (Macdonald, Newman, Stewart, Domingo-Roura, & Johnson, 2002; Simmonds, Cole, Sheldon, & Coulson, 2020)) and remote sensing approaches ( e.g. , tagging, drone-monitoring projects (Cubaynes et al, 2022)). These datasets, and recent advances in MPM theory and methods, enable researchers to link population dynamics and demography to environmental conditions and multiple individual traits ( e.g.…”