Insights into the evolution of Darwin’s finches from comparative analysis of the Geospiza magnirostris genome sequence

Title: Insights into the evolution of Darwin’s finches from comparative analysis of the Geospiza magnirostris genome sequence
Author(s): Rands, CM
Darling, A
Fujita, M
Kong, L
Webster, MT
Clabaut, C
Emes, RD
Heger, A
Meader, S
Hawkins, MB
Eisen, MB
Teiling, C
Affourtit, J
Boese, B
Grant, PR
Grant, BR
Eisen, JA
Abzhanov, A
Ponting, CP
Item Type: Journal Article
Abstract: BACKGROUND: A classical example of repeated speciation coupled with ecological diversification is the evolution of 14 closely related species of Darwin's (Galápagos) finches (Thraupidae, Passeriformes). Their adaptive radiation in the Galápagos archipelago took place in the last 2-3 million years and some of the molecular mechanisms that led to their diversification are now being elucidated. Here we report evolutionary analyses of genome of the large ground finch, Geospiza magnirostris. RESULTS: 13,291 protein-coding genes were predicted from a 991.0 Mb G. magnirostris genome assembly. We then defined gene orthology relationships and constructed whole genome alignments between the G. magnirostris and other vertebrate genomes. We estimate that 15% of genomic sequence is functionally constrained between G. magnirostris and zebra finch. Genic evolutionary rate comparisons indicate that similar selective pressures acted along the G. magnirostris and zebra finch lineages suggesting that historical effective population size values have been similar in both lineages. 21 otherwise highly conserved genes were identified that each show evidence for positive selection on amino acid changes in the Darwin's finch lineage. Two of these genes (Igf2r and Pou1f1) have been implicated in beak morphology changes in Darwin's finches. Five of 47 genes showing evidence of positive selection in early passerine evolution have cilia related functions, and may be examples of adaptively evolving reproductive proteins. CONCLUSIONS: These results provide insights into past evolutionary processes that have shaped G. magnirostris genes and its genome, and provide the necessary foundation upon which to build population genomics resources that will shed light on more contemporaneous adaptive and non-adaptive processes that have contributed to the evolution of the Darwin's finches.
Publication Date: 12-Feb-2013
Date of Acceptance: 23-Jan-2013
ISSN: 1471-2164
Publisher: BioMed Central
Journal / Book Title: BMC Genomics
Volume: 14
Copyright Statement: This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Keywords: Adaptation, Physiological
Evolution, Molecular
Genetics, Population
Models, Genetic
Sequence Homology, Nucleic Acid
Genetics, Population
Adaptation, Physiological
Evolution, Molecular
Sequence Homology, Nucleic Acid
Models, Genetic
06 Biological Sciences
11 Medical And Health Sciences
08 Information And Computing Sciences
Publication Status: Published
Article Number: 95
Appears in Collections:Faculty of Natural Sciences

Items in Spiral are protected by copyright, with all rights reserved, unless otherwise indicated.

Creative Commons