Inferring the History of Speciation from Multilocus DNA Sequence Data: The Case of Drosophila pseudoobscura and Close Relatives

Machado, Carlos A.; Kliman, Richard M.; Markert, Jeffrey A.; Hey, Jody

doi:10.1093/oxfordjournals.molbev.a004103

Cited by 302 publications

(393 citation statements)

References 75 publications

Supporting

Mentioning

351

Contrasting

Order By: Relevance

“…Lower gene exchanges or higher genetic divergences across genomic regions differing by chromosomal rearrangements have been detected between species of flies (Noor et al, 2001;Machado et al, 2002;Ortiz-Barrientos et al, 2002) or sunflowers (Rieseberg et al, 1999), between chromosomal races of house mouse (Panithanarak et al, 2004) or between human and chimpanzee (Navarro and Barton, 2003b). However, species for which genetic maps are available (for example, sunflower, house mice or humans) are scarce, and additional empiric studies from non-model species are of primary importance.…”

Section: General Conclusionmentioning

confidence: 99%

Chromosomal rearrangements and gene flow over time in an inter-specific hybrid zone of the Sorex araneus group

2009

View full text Add to dashboard Cite

Most hybrid zones have existed for hundreds or thousands of years but have generally been observed for only a short time period. Studies extending over periods long enough to track evolutionary changes in the zones or assess the ultimate outcome of hybridization are scarce. Here, we describe the evolution over time of the level of genetic isolation between two karyotypically different species of shrews (Sorex araneus and Sorex antinorii) at a hybrid zone located in the Swiss Alps. We first evaluated hybrid zone movement by contrasting patterns of gene flow and changes in cline parameters (centre and width) using 24 microsatellite loci, between two periods separated by 10 years apart. Additionally, we tested the role of chromosomal rearrangements on gene flow by analysing microsatellite loci located on both rearranged and common chromosomes to both species. We did not detect any movement of the hybrid zone during the period analysed, suggesting that the zone is a typical tension zone. However, the gene flow was significantly lower among the rearranged than the common chromosomes for the second period, whereas the difference was only marginally significant for the first period. This further supports the role of chromosomal rearrangements on gene flow between these taxa.

show abstract

Section: General Conclusionmentioning

confidence: 99%

Chromosomal rearrangements and gene flow over time in an inter-specific hybrid zone of the Sorex araneus group

2009

View full text Add to dashboard Cite

show abstract

“…Based on sequence analyses and genetic mapping data, we inferred that gene flow has homogenized the collinear regions of D. pseudoobscura and D. persimilis [2,4,5,34], but sequence divergence is maintained in and approximately 2.5 Mb outside of the chromosome 2, XL and XR inversions owing to reduced recombination [2,4 -6,34]. Little reduction of divergence toward the centre of these inversions is observed [2,5,6].…”

Section: Introductionmentioning

confidence: 99%

Genomic impacts of chromosomal inversions in parapatricDrosophilaspecies

McGaugh

Noor

2012

Phil. Trans. R. Soc. B

115

140

View full text Add to dashboard Cite

Chromosomal inversions impact genetic variation and facilitate speciation in part by reducing recombination in heterokaryotypes. We generated multiple whole-genome shotgun sequences of the parapatric species pair Drosophila pseudoobscura and Drosophila persimilis and their sympatric outgroup (Drosophila miranda) and compared the average pairwise differences for neutral sites within, just outside and far outside of the three large inversions. Divergence between D. pseudoobscura and D. persimilis is high inside the inversions and in the suppressed recombination regions extending 2.5 Mb outside of inversions, but significantly lower in collinear regions further from the inversions. We observe little evidence of decreased divergence predicted to exist in the centre of inversions, suggesting that gene flow through double crossovers or gene conversion is limited within the inversion, or selection is acting within the inversion to maintain divergence in the face of gene flow. In combination with past studies, we provide evidence that inversions in this system maintain areas of high divergence in the face of hybridization, and have done so for a substantial period of time. The left arm of the X chromosome and chromosome 2 inversions appear to have arisen in the lineage leading to D. persimilis approximately 2 Ma, near the time of the split of D. persimilis-D. pseudoobscura-D. miranda, but likely fixed within D. persimilis much more recently, as diversity within D. persimilis is substantially reduced inside and near these two inversions. We also hypothesize that the inversions in D. persimilis may provide an empirical example of the 'mixed geographical mode' theory of inversion origin and fixation, whereby allopatry and secondary contact both play a role.

show abstract

“…One of the most striking examples may be the 'replicated time series of evolution in action' in Drosophila subobscura (Prevosti et al, 1988;Gilchrist et al, 2004), but other fascinating cases have also been identified in other animal species (for example, grasshoppers in Shaw et al, 1985;Drosophila in Hoffman et al, 2004; Anopheles in Coluzzi et al, 2002;humans in Stefansson et al, 2005). In some instances, adaptive gradients may result in considerable divergence such that they finally lead to speciation (for example, Drosophila: Noor et al, 2001;Machado et al, 2002;Anopheles: Coluzzi et al, 2002;Rhagoletis: Feder et al, 2005).…”

Section: Introductionmentioning

confidence: 99%

Geographic patterns of inversion polymorphisms in a wild African rodent, Mastomys erythroleucus

et al. 2009

View full text Add to dashboard Cite

By suppressing recombination and reducing gene flow, chromosome inversions favor the capture and protection of advantageous allelic combinations, leading to adaptive polymorphisms. However, studies in non-model species remain scarce. Here we investigate the distribution of inversion polymorphisms in the multimammate rat Mastomys erythroleucus in West Africa. More than 270 individuals from 52 localities were karyotyped using G-bands and showed widespread polymorphisms involving four chromosome pairs. No significant deviations from Hardy-Weinberg equilibrium were observed either through space or time, nor were differences retrieved in viability or sex contribution between cytotypes. The distribution of chromosomal variation, however, showed perfect congruence with that of mtDNAbased phylogeographic clades. Thus, inversion diversity patterns in M. erythroleucus appeared more related to historical and/or demographic processes than to climatebased adaptive features. Using cross-species chromosome painting and G-banding analyses to identify homologous chromosomes in related out-group species, we proposed a phylogenetic scenario that involves ancestral-shared polymorphisms and subsequent lineage sorting during expansion/contraction of West African savannas. Our data suggest that long-standing inversion polymorphisms may act as regions in which adaptation genes may accumulate (nucleation model).

show abstract

Inferring the History of Speciation from Multilocus DNA Sequence Data: The Case of Drosophila pseudoobscura and Close Relatives

Cited by 302 publications

References 75 publications

Chromosomal rearrangements and gene flow over time in an inter-specific hybrid zone of the Sorex araneus group

Chromosomal rearrangements and gene flow over time in an inter-specific hybrid zone of the Sorex araneus group

Genomic impacts of chromosomal inversions in parapatricDrosophilaspecies

Geographic patterns of inversion polymorphisms in a wild African rodent, Mastomys erythroleucus

Contact Info

Product

Resources

About