title: Expert-based versus habitat-suitability models to develop resistance surfaces in landscape genetics.
abstract: Landscape genetics aims to investigate functional connectivity among wild populations by evaluating the impact of landscape features on gene flow. Genetic distances among populations or individuals are generally better explained by least-cost path (LCP) distances derived from resistance surfaces than by simple Euclidean distances. Resistance surfaces reflect the cost for an organism to move through particular landscape elements. However, determining the effects of landscape types on movements is challenging. Because of a general lack of empirical data on movements, resistance surfaces mostly rely on expert knowledge. Habitat-suitability models potentially provide a more objective method to estimate resistance surfaces than expert opinions, but they have rarely been applied in landscape genetics so far. We compared LCP distances based on expert knowledge with LCP distances derived from habitat-suitability models to evaluate their performance in landscape genetics. We related all LCP distances to genetic distances in linear mixed effect models on an empirical data set of wolves (Canis lupus) from Italy. All LCP distances showed highly significant (P ≤ 0.0001) standardized β coefficients and R2values, but LCPs from habitat-suitability models generally showed higher values than those resulting from expert knowledge. Moreover, all LCP distances better explained genetic distances than Euclidean distances, irrespective of the approaches used. Considering our results, we encourage researchers in landscape genetics to use resistance surfaces based on habitat suitability which performed better than expert-based LCPs in explaining patterns of gene flow and functional connectivity.
authors.affiliation: Laboratorio di Genetica, Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Via Ca` Fornacetta 9, 40064, Ozzano dell'Emilia, Bologna, Italy. pietro.milanesi@unipv.it.|WSL Swiss Federal Research Institute, Zürcherstrasse 111, 8903, Birmensdorf, Switzerland. pietro.milanesi@unipv.it.
authors.forename: Pietro
authors.identifier: http://orcid.org/0000-0002-1878-9762
authors.initials: P
authors.lastname: Milanesi
authors.affiliation: WSL Swiss Federal Research Institute, Zürcherstrasse 111, 8903, Birmensdorf, Switzerland.|Institute of Integrative Biology, ETH Zürich, Universitätstrasse 16, 8092, Zurich, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Holderegger
authors.affiliation: Laboratorio di Genetica, Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Via Ca` Fornacetta 9, 40064, Ozzano dell'Emilia, Bologna, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Caniglia
authors.affiliation: Laboratorio di Genetica, Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Via Ca` Fornacetta 9, 40064, Ozzano dell'Emilia, Bologna, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Fabbri
authors.affiliation: Laboratorio di Genetica, Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Via Ca` Fornacetta 9, 40064, Ozzano dell'Emilia, Bologna, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Galaverni
authors.affiliation: Laboratorio di Genetica, Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Via Ca` Fornacetta 9, 40064, Ozzano dell'Emilia, Bologna, Italy.|Department 18/Section of Environmental Engineering, Aalborg University, Sohngårdsholmsvej 57, 9000, Aalborg, Denmark.
authors.forename: E
authors.initials: E
authors.lastname: Randi
mesh_terms: D017753:Ecosystem; D051456:Gene Flow; D005828:Genetics, Population; D016014:Linear Models; D008962:Models, Theoretical
keywords: Canis lupus; Expert knowledge; Least-cost path distances; Linear mixed effect models; Species distribution models