title: Partitioning global patterns of freshwater fish beta diversity reveals contrasting signatures of past climate changes.
abstract: Here, we employ an additive partitioning framework to disentangle the contribution of spatial turnover and nestedness to beta diversity patterns in the global freshwater fish fauna. We find that spatial turnover and nestedness differ geographically in their contribution to freshwater fish beta diversity, a pattern that results from contrasting influences of Quaternary climate changes. Differences in fish faunas characterized by nestedness are greater in drainage basins that experienced larger amplitudes of Quaternary climate oscillations. Conversely, higher levels of spatial turnover are found in historically unglaciated drainage basins with high topographic relief, these having experienced greater Quaternary climate stability. Such an historical climate signature is not clearly detected when considering the overall level of beta diversity. Quantifying the relative roles of historical and ecological factors in explaining present-day patterns of beta diversity hence requires considering the different processes generating these patterns and not solely the overall level of beta diversity.
authors.affiliation: UMR 5119 "Ecosystèmes Lagunaires"-CNRS-IFREMER-UM2-IRD, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier, France. fabien.leprieur@univ-montp2.fr
authors.forename: Fabien
authors.initials: F
authors.lastname: Leprieur
authors.forename: Pablo A
authors.initials: PA
authors.lastname: Tedesco
authors.forename: Bernard
authors.initials: B
authors.lastname: Hugueny
authors.forename: Olivier
authors.initials: O
authors.lastname: Beauchard
authors.forename: Hans H
authors.initials: HH
authors.lastname: Dürr
authors.forename: Sébastien
authors.initials: S
authors.lastname: Brosse
authors.forename: Thierry
authors.initials: T
authors.lastname: Oberdorff
mesh_terms: D000818:Animals; D044822:Biodiversity; D002980:Climate; D057231:Climate Change; D004777:Environment; D005399:Fishes / Q000145:classification* / Q000502:physiology; D005618:Fresh Water; D005843:Geography; D011157:Population Dynamics