Combining Bayesian genetic clustering and ecological niche modeling: Insights into wolf intraspecific genetic structure.

Pietro Milanesi,Felice Puopolo,Rolf Holderegger,Marco Galaverni,Elena Fabbri,Romolo Caniglia

doi:10.1002/ece3.4594

Abstract

The distribution of intraspecific genetic variation and how it relates to environmental factors is of increasing interest to researchers in macroecology and biogeography. Recent studies investigated the relationships between the environment and patterns of intraspecific genetic variation across species ranges but only few rigorously tested the relation between genetic groups and their ecological niches. We quantified the relationship of genetic differentiation (F ST) and the overlap of ecological niches (as measured by n‐dimensional hypervolumes) among genetic groups resulting from spatial Bayesian genetic clustering in the wolf (Canis lupus) in the Italian peninsula. Within the Italian wolf population, four genetic clusters were detected, and these clusters showed different ecological niches. Moreover, different wolf clusters were significantly related to differences in land cover and human disturbance features. Such differences in the ecological niches of genetic clusters should be interpreted in light of neutral processes that hinder movement, dispersal, and gene flow among the genetic clusters, in order to not prematurely assume any selective or adaptive processes. In the present study, we found that both the plasticity of wolves—a habitat generalist—to cope with different environmental conditions and the occurrence of barriers that limit gene flow lead to the formation of genetic intraspecific genetic clusters and their distinct ecological niches.

Highlights

Genetic variation is key for the long‐term persistence and survival of species and populations
Recent studies investigated the relationships between the environment and patterns of intraspecific genetic variation across species ranges but only few rigorously tested the relation between genetic groups and their ecological niches
Gotelli and Stanton‐Geddes (2015) proposed the use of ecological niche models (ENMs), known as habitat suitability models or species distribution models, for intraspecific genetic groups identified by Bayesian clustering, in order to ac‐ count for the genetic diversity occurring within species

Summary

| INTRODUCTION

Genetic variation is key for the long‐term persistence and survival of species and populations. The approach of Gotelli and Stanton‐Geddes (2015) has so far only been applied in handful of studies (Harrisson et al, 2016; Ikeda et al, 2017; Marcer et al, 2016; Shinneman, Means, Potter, & Hipkins, 2016) , and the relationship between genetic distances among genetically defined clusters (e.g., genetic differentiation FST; Dupanloup, Schneider, & Excoffier, 2002; Jombart, Devillard, Dufour, & Pontier, 2008) and distances or similarities among their ecological niches (e.g., niche overlap) has not been tested so far None of these studies investigated the environmental factors differing among genetic clusters. In about 40 years, the wolf population re‐expanded from south‐central Italy to the entire Apennine chain (including ad‐ jacent lower hills and plains) and the Italian and French western Alps (Caniglia et al, 2013; Fabbri et al, 2007; Galaverni, Caniglia, Fabbri, Milanesi, & Randi, 2016)

| METHODS

| DISCUSSION

Findings

CONFLICT OF INTEREST