Genomics of Parallel Ecological Speciation in Lake Victoria Cichlids

Meier, Joana; Marques, David Alexander; Wagner, Catherine Elise; Excoffier, Laurent; Seehausen, Ole (2018). Genomics of Parallel Ecological Speciation in Lake Victoria Cichlids. Molecular Biology and Evolution, 35(6), pp. 1489-1506. Oxford University Press 10.1093/molbev/msy051

[img] Text
msy051.pdf - Published Version
Restricted to registered users only
Available under License Publisher holds Copyright.

Download (1MB) | Request a copy
[img] Text
Meier_et_al-18-MBE_postprint.pdf - Accepted Version
Restricted to registered users only until 3 April 2019.
Available under License Publisher holds Copyright.

Download (1MB) | Request a copy

The genetic basis of parallel evolution of similar species is of great interest in evolutionary biology. In the adaptive radiation of Lake Victoria cichlid fishes, sister species with either blue or red-back male nuptial coloration have evolved repeatedly, often associated with shallower and deeper water, respectively. One such case is blue and red-backed Pundamilia species, for which we recently showed that a young species pair may have evolved through “hybrid parallel speciation”. Coalescent simulations suggested that the older species P. pundamilia (blue) and P. nyererei (red-back) admixed in the Mwanza Gulf and that new “nyererei-like” and “pundamilia-like” species evolved from the admixed population. Here, we use genome scans to study the genomic architecture of differentiation, and assess the influence of hybridization on the evolution of the younger species pair. For each of the two species pairs, we find over 300 genomic regions, widespread across the genome, which are highly differentiated. A subset of the most strongly differentiated regions of the older pair are also differentiated in the younger pair. These shared differentiated regions often show parallel allele frequency differences, consistent with the hypothesis that admixture-derived alleles were targeted by divergent selection in the hybrid population. However, two-thirds of the genomic regions that are highly differentiated between the younger species are not highly differentiated between the older species, suggesting independent evolutionary responses to selection pressures. Our analyses reveal how divergent selection on admixture-derived genetic variation can facilitate new speciation events.

Item Type:

Journal Article (Original Article)

Division/Institute:

08 Faculty of Science > Department of Biology > Institute of Ecology and Evolution (IEE)
08 Faculty of Science > Department of Biology > Institute of Ecology and Evolution (IEE) > Population Genetics
08 Faculty of Science > Department of Biology > Institute of Ecology and Evolution (IEE) > Aquatic Ecology

UniBE Contributor:

Meier, Joana; Marques, David Alexander; Excoffier, Laurent and Seehausen, Ole

Subjects:

500 Science > 570 Life sciences; biology

ISSN:

0737-4038

Publisher:

Oxford University Press

Language:

English

Submitter:

Marcel Häsler

Date Deposited:

24 May 2018 10:51

Last Modified:

28 May 2018 10:05

Publisher DOI:

10.1093/molbev/msy051

BORIS DOI:

10.7892/boris.116578

URI:

https://boris.unibe.ch/id/eprint/116578

Actions (login required)

Edit item Edit item
Provide Feedback