Biogeographical signature of river capture events in Amazonian lowlands

Abstract

Aim To investigate the effects of river capture on the biogeographical history of South American freshwater fishes.Location Western Amazon and La Plata basins, and adjacent river drainages. MethodsWe used a species-dense time-calibrated phylogeny of longwhiskered catfishes (Siluriformes, Pimelodidae) to calculate likelihoods for 16 biogeographical scenarios of river capture, each differing in details of (1) landscape evolution and/or (2) models of species range evolution. We designed eight alternative landscape evolution models (LEMs) to represent distinct palaeogeographical river capture histories between the Western Amazon and La Plata drainages during the formation of the Central Andean (Bolivian) orocline (43.0-15.0 Ma). The LEMs differed only in patterns of area-connectivity constraints through time, and otherwise had the same geographical areas, time durations and dispersal probabilities. We used the DEC and DECj models of species range evolution under these eight LEM constraints to calculate likelihood values for ancestral area estimates.Results Divergence time estimates indicated that crown-group pimelodids emerged during the Late Cretaceous or Palaeogene (c. 72.9 AE 20 Ma) and model-selection recovered a best-fit palaeogeographical scenario with (1) a LEM with three river capture events, and (2) a DECj model of species range evolution. These results were quantitatively replicated using Lagrange and BayArea-like methods.Main conclusions The taxon-area chronogram of pimelodids exhibits the characteristic biogeographical signature of river capture; i.e. several non-monophyletic regional (basin-wide) species assemblages coupled with the presence of many species inhabiting more than one basin. These phylogenetic and biogeographical patterns are consistent with the effects of three large-scale river capture events during the formation of the Bolivian orocline.

Why does freshwater fish species richness differ between Pacific and Atlantic drainages of the Americas?

“…Changes in across-drainage connectivity, by river capture (Tagliacollo, Roxo, Duke-Sylvester, Oliveira, & Albert, 2015), changes in aridity (Oberdorff et al, 1999) and glaciation-driven changes in sea level (Dias et al, 2014) can affect freshwater fish richness and endemism. The development of mountain ranges on the western side of the Americas created barriers to species movement (of varying permeability), and the narrower Pacific continental shelf suggests that Pacific drainages were more likely to remain isolated than Atlantic ones when sea levels fell during glaciations.…”

Biogeography of Amazonian fishes: deconstructing river basins as biogeographic units

“…Biotic dispersal has been a major factor in historical hybridization and diversity generation in Amazonian rivers. This is a consequence of the importance of neotectonic activity and resulting rearrangements in the drainage network as diversity-generating factors, both in freshwater fishes in general (Burridge et al, 2006Cardoso, Montoya-Burgos, 2009;Waters et al, 2007) and neotropical fishes in particular Lima, Ribeiro, 2011;Ribeiro et al, 2013;Roxo et al, 2014;Tagliacollo et al, 2015). Those observations and ensuing conclusions prompt a reevaluation of the assumption that vicariant and dispersalist events in their pure form are the best explanation for the diversification of the neotropical fish fauna.…”

Transcontinental dispersal, ecological opportunity and origins of an adaptive radiation in the Neotropical catfish genusHypostomus(Siluriformes: Loricariidae)

“…; Tagliacollo et al . ). Indeed, geomorphological processes involving both the division of previously contiguous populations and the passive geodispersal of species between drainages have been linked to freshwater fish speciation and diversification both theoretically and empirically (Grant et al .…”

“…Moreover, physical connections and slopes between and within these habitats shift in response to geomorphic processes. Phylogenies of freshwater fishes often reflect these events (Smith 1981;Hocutt & Wiley 1986;Mayden 1988;Lundberg et al 1998;Cardoso et al 2012;Lujan et al 2015a;Tagliacollo et al 2015). Indeed, geomorphological processes involving both the division of previously contiguous populations and the passive geodispersal of species between drainages have been linked to freshwater fish speciation and diversification both theoretically and empirically (Grant et al 2007;Muneepeerakul et al 2008;Winemiller et al 2008;Bertuzzo et al 2009;Albert & Crampton 2010).…”