Recent demographic history of cactophilic Drosophila species can be related to Quaternary palaeoclimatic changes in South America

Abstract

Aim The aim of this paper is to investigate the influence and extent of past climatic changes on South American biota. To this end, we establish phylogeographical hypotheses for a monophyletic group of four cactophilic species of Drosophila (the Drosophila serido haplogroup) found in xeromorphic vegetation in Brazil. The effects of Quaternary palaeoclimatic oscillations on the demographic fluctuations of our biological model and its sister group Drosophila antonietae are investigated. Location Areas of eastern Brazil with open vegetation, including seasonally dry tropical forest (SDTF) areas and montane savannas, which are disjunctly distributed in eastern Brazil. We also analysed populations of sand dune vegetation from littoral areas in Brazil. Methods Nucleotide information from 630 bp of the cytochrome c oxidase subunit I gene from 441 individuals was used to perform a series of statistical analyses to infer a phylogeographical hypothesis for each species and to date the divergence time between the D. serido and D. antonietae haplogroups. Results All of the analysed species experienced population expansion during the Pleistocene, probably following the historical migratory routes that have been proposed for the expansion of SDTFs in Brazil. A bottleneck event in the Holocene was inferred for Drosophila seriema, probably due to ecological factors related to the geographical distribution of the host plant. The divergence time for the D. serido and D. antonietae haplogroups was calculated to have occurred during the early Pleistocene. Main conclusions Geographical and chronological evidence suggests that the major vicariant events between the D. serido and D. antonietae haplogroups, as well as the demographic fluctuations in each of the species within these lineages, could be related to the causal effects of Quaternary palaeoclimatic changes on the spatial dynamics of the SDTFs in Brazil.

Model-based analysis supports interglacial refugia over long-dispersal events in the diversification of two South American cactus species

“…Phylogeographical studies on plant and animal species associated to these habitats have pointed to the Pleistocene climatic fluctuations and their demographic consequences as an important diversification mechanism accounting to the high diversity and endemism of rocky savanna habitats in eastern South America (Moraes et al, 2009;Barbosa et al, 2012;Franco and Manfrin, 2013;Collevatti et al, 2009Collevatti et al, , 2013Bonatelli et al, 2014;Machado et al, 2014). These studies have provided growing support to the hypothesis that rocky savannas in Eastern South America are interglacial refuge for xerophytic species.…”

“…Importantly, these estimates were similar to those obtained from two cpDNA and one nuclear gene (Bonatelli et al, 2014), supporting that the splitting times for the most ancient lineages in the two species took place primarily during the early Pleistocene whereas the derived lineages diversified in a period within the early and middle Pleistocene. These estimates fell within a period characterized by range shifts in dry vegetation (Prado and Gibbs, 1993;Pennington et al, 2004) and also recognized as an age of speciation and intraspecific differentiation of other species associated with the open and xeric environments in eastern Brazil, such as the rodent species of the genus Calomys (Almeida et al, 2007) and some cactophilic drosophilids of the D. buzatti cluster (Moraes et al, 2009;Franco and Manfrin, 2013).…”

Estimating synchronous demographic changes across populations using hABC and its application for a herpetological community from northeastern Brazil

“…Several palaeontological studies show dynamic climatic changes in northeastern Brazil for the last 1 Mya, with periods of aridity and changes in the Caatinga vegetation (Auler & Smart, ; Auler et al., ; De Oliveira, Magno, & Suguio, ; Wang et al., ). Many phylogeographic studies show evidence of population and/or range expansion for Caatinga species (Caetano et al., ; Faria, Nascimento, De Oliveira, & Bonvicino, ; Franco & Manfrin, ; Magalhaes et al., ; Monteiro, Donnelly, Beard, & Costa, ; Oliveira et al., ; Thomé et al., ; Werneck, Leite, Geurgas, & Rodrigues, ), although our study uniquely models historical demography at the community level using hABC.…”

Mito-nuclear discordance with evidence of shared ancestral polymorphism and selection in cactophilic species ofDrosophila

“…The AIC, BIC and DT agree in the selection of TVMef + I + G and HKY + I + G (Hasegawa, Kishino & Yano, ) as the best models for α‐Est5 and per, respectively. For COI we assumed the GTR + I + G model, as previously estimated to explain nucleotide evolution of this gene in the D. serido haplogroup (Franco & Manfrin, ).…”