New publication: The genomic mosaicism of hybrid speciation

By Tore O. Elgvin*1Cassandra N. Trier*1Ole K. Tørresen*, Ingerid J. Hagen#, Sigbjørn Lien§, Alexander J. Nederbragt*, Mark Ravinet*, Henrik Jensen#, and Glenn-Peter Sætre* in Science Advances. Open access.

Abstract

Hybridization is widespread in nature and, in some instances, can result in the formation of a new hybrid species. We investigate the genetic foundation of this poorly understood process through whole-genome analysis of the hybrid Italian sparrow and its progenitors. We find overall balanced yet heterogeneous levels of contribution from each parent species throughout the hybrid genome and identify areas of novel divergence in the hybrid species exhibiting signals consistent with balancing selection. High-divergence areas are disproportionately located on the Z chromosome and overrepresented in gene networks relating to key traits separating the focal species, which are likely involved in reproductive barriers and/or species-specific adaptations. Of special interest are genes and functional groups known to affect body patterning, beak morphology, and the immune system, which are important features of diversification and fitness. We show that a combination of mosaic parental inheritance and novel divergence within the hybrid lineage has facilitated the origin and maintenance of an avian hybrid species.


Science Advances
14 Jun 2017
Vol. 3, no. 6, e1602996
DOI: 10.1126/sciadv.1602996
Publication webpage.

* Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, UiO, Oslo, Norway.
# Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, Trondheim, Norway
§ Department of Animal and Aquacultural Sciences, Faculty for Biosciences, Centre for Integrative Genetics, Norwegian University of Life Sciences, Ås, Norway
1 These authors contributed equally to this work.
See the publication webpage for full author information.

Tags: Science Advances;
Published June 16, 2017 9:58 AM - Last modified June 16, 2017 10:24 AM