title: Timetree of Aselloidea reveals species diversification dynamics in groundwater.
abstract: A key challenge for biologists is to document and explain global patterns of diversification in a wide range of environments. Here, we explore patterns of continental-scale diversification in a groundwater species-rich clade, the superfamily Aselloidea (Pancrustacea: Isopoda). Our analyses supported a constant diversification rate during most of the course of Aselloidea evolution, until 4-15 Ma when diversification rates started to decrease. This constant accumulation of lineages challenges the view that groundwater species diversification in temperate regions might have been primarily driven by major changes in physical environment leading to the extinction of surface populations and subsequent synchronous isolation of multiple groundwater populations. Rather than acting synchronously over broad geographic regions, factors causing extinction of surface populations and subsequent reproductive isolation of groundwater populations may act in a local and asynchronous manner, thereby resulting in a constant speciation rate over time. Our phylogeny also revealed several cases of parapatric distributions among closely related surface-water and groundwater species suggesting that species diversification could also arise from a process of disruptive selection along the surface-subterranean environmental gradient. Our results call for re-evaluating the spatial scale and timing of factors causing diversification events in groundwater.
authors: UMR5023 Ecologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1, Université de Lyon, ENTPE, CNRS, 6 Rue Raphaël Dubois, 69622 Villeurbanne, France.
authors: Claire
authors: C
authors: Morvan
authors: Florian
authors: F
authors: Malard
authors: Emmanuel
authors: E
authors: Paradis
authors: Tristan
authors: T
authors: Lefébure
authors: Lara
authors: L
authors: Konecny-Dupré
authors: Christophe J
authors: CJ
authors: Douady
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D005075:Biological Evolution; D003576:Electron Transport Complex IV / Q000235:genetics / Q000378:metabolism; D005060:Europe; D019143:Evolution, Molecular; D019419:Evolution, Planetary; D049810:Genetic Speciation; D060587:Groundwater; D033321:Isopoda / Q000145:classification* / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D014481:United States
chemical_list: D003576:Electron Transport Complex IV