Edinburgh Research Explorer

Maintaining their genetic distance: little evidence for introgression between widely hybridising species of Geum with contrasting mating systems

Research output: Contribution to journalArticle

Related Edinburgh Organisations

Open Access permissions

Open

Documents

  • Download as Adobe PDF

    Rights statement: This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. ©2017 The Authors. Molecular EcologyPublished by John Wiley & Sons Ltd

    Final published version, 910 KB, PDF document

    Licence: Creative Commons: Attribution (CC-BY)

Original languageEnglish
Number of pages15
JournalMolecular Ecology
Early online date13 Nov 2017
DOIs
Publication statusPublished - 9 Dec 2017

Abstract

Within the plant kingdom many genera contain sister lineages with contrasting outcrossing and inbreeding mating systems that are known to hybridise. The evolutionary fate of these sister lineages is likely to be influenced by the extent to which they exchange genes. We measured gene flow between outcrossing Geum rivale and selfing Geum urbanum, sister species that hybridise in contemporary populations. We generated and used a draft genome of G. urbanum to develop dd-RAD data scorable in both species. Coalescent analysis of RAD data from allopatric populations indicated that the species diverged 2-3 Mya, and that historical gene flow between them was extremely low (1 migrant every 25 generations). Comparison of genetic divergence between species in sympatry and allopatry, together with an analysis of allele frequencies in potential parental and hybrid populations, provided no evidence of contemporary introgression in sympatric populations. Cluster and species specific marker analyses revealed that, apart from four early generation hybrids, individuals in sympatric populations fell into two genetically distinct groups that corresponded exactly to their morphological species classification with maximum individual admixture estimates of only 1 -3%. However, we did observe joint segregation of four putatively introgressed SNPs across two scaffolds in the G. urbanum population that was associated with significant morphological variation, interpreted as tentative evidence for rare, recent interspecific gene flow. Overall, our results indicate that despite the presence of hybrids in contemporary populations, genetic exchange between G. rivale and G. urbanum has been extremely limited throughout their evolutionary history. 

    Research areas

  • Geum, coalescent, hybridization, introgression, natural selection

Download statistics

No data available

ID: 47174387