Evolution of Darwin’s finches and their beaks revealed by genome sequencing

  title={Evolution of Darwin’s finches and their beaks revealed by genome sequencing},
  author={Sangeet Lamichhaney and Jonas Berglund and Markus S{\"a}llman Alm{\'e}n and Khurram Maqbool and Manfred G. Grabherr and Alvaro Martinez-Barrio and Marta Promerov{\'a} and Carl-Johan Rubin and Chao Wang and Neda Zamani and Barbara Rosemary Grant and Peter R. Grant and Matthew T. Webster and Leif Andersson},
Darwin’s finches, inhabiting the Galápagos archipelago and Cocos Island, constitute an iconic model for studies of speciation and adaptive evolution. Here we report the results of whole-genome re-sequencing of 120 individuals representing all of the Darwin’s finch species and two close relatives. Phylogenetic analysis reveals important discrepancies with the phenotype-based taxonomy. We find extensive evidence for interspecific gene flow throughout the radiation. Hybridization has given rise to… 
Evolution: Finches sequenced
This study shows how a haplotype encompassing the ALX1 gene encoding a transcription factor affecting craniofacial development is strongly associated with beak shape diversity across Darwin's finches and in the medium ground finch (a species that has undergone rapid evolution ofBeak shape in response to environmental changes).
Darwin’s finches - an adaptive radiation constructed from ancestral genetic modules
A highly contiguous genome assembly for one of the species is presented and the genomic architecture underlying phenotypic diversity in the entire radiation is investigated, which can be critical for how species adapt to environmental variability and change.
Adaptive radiation of Darwin's finches revisited using whole genome sequencing
Evidence is uncovered that segregation of two haplotypes at the ALX1 locus underlies variation in beak shape among the Darwin's finches, and that differences between the two haplotype in a 240 kb region in blunt and pointed beaked birds involve both coding and regulatory changes.
Divergence and gene flow among Darwin's finches: A genome‐wide view of adaptive radiation driven by interspecies allele sharing
  • D. PalmerM. Kronforst
  • Biology
    BioEssays : news and reviews in molecular, cellular and developmental biology
  • 2015
These latest findings affirm the increasing acceptance of introgressive hybridization, or gene flow between species, as a significant contributor to adaptive evolution in Darwin's finches and well beyond.
A beak size locus in Darwin’s finches facilitated character displacement during a drought
A genome-wide analysis in finches identifies loci associated with parallel size variation in the Galápagos and discovered a genomic region containing the HMGA2 gene that varies systematically among Darwin’s finch species with different beak sizes.
Population genomics fits the bill: genetics of adaptive beak variation in Darwin's finches
The study confirms that loci of large effect are involved in beak size variation, which helps to explain the high heritability and rapid response to selection of this trait, and shows that under the right conditions, RAD‐seq can be a viable alternative to genome sequencing for GWAS in wild vertebrate populations.
Rapid adaptive radiation of Darwin’s finches depends on ancestral genetic modules
Admixture mapping for beak and body size in the small, medium, and large ground finches revealed 28 loci showing strong genetic differentiation that represent ancestral haplotype blocks with origins predating speciation events during the Darwin’s finch radiation.
The adaptive genomic landscape of beak morphology in Darwin's finches
The adaptive genomic landscape for Darwin's finches mirrors theoretical expectations based on morphological variation and the implication that a large number of genes are actively maintained to facilitate beak variation across parallel populations with documented interspecies admixture challenges the understanding of evolutionary processes in the wild.
Ecological and morphological determinants of evolutionary diversification in Darwin's finches and their relatives
Analysis of the evolutionary dynamics of speciation and trait diversification in Thraupidae illustrates how the exploitation of ecological opportunity by contrasting means can produce clades with similarly high diversification rate yet strikingly different degrees of ecological and morphological differentiation.
Biogeographic origins of Darwin's finches (Thraupidae: Coerebinae)
The ancestral biogeography of Coerebinae, the tanager subfamily that contains Darwin's finches and their 14 closest relatives is reconstructed to examine the origin of Darwin'sfinches, and the diversification of this clade of tanagers.


Insights into the evolution of Darwin’s finches from comparative analysis of the Geospiza magnirostris genome sequence
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.
40 Years of Evolution: Darwin's Finches on Daphne Major Island
The authors find that natural selection happens repeatedly, that finches hybridize and exchange genes rarely, and that they compete for scarce food in times of drought, with the remarkable result that the finch populations today differ significantly in average beak size and shape from those of forty years ago.
A landscape perspective highlights a likely role for isolation of peripheral populations in initial divergence, and demonstrates that peripheral populations may maintain genetic diversity through outbreeding during the initial stages of speciation.
  • D. SchluterP. Grant
  • Biology, Environmental Science
    Evolution; international journal of organic evolution
  • 1984
Lack (1947) provided the first detailed arguments for the adaptive significance of morphological variation in Darwin's finches, and stressed two aspects: first, that several morphological features are related to feeding, and second, that morphological differences between populations may be associated with inter-island differences in the type and number of potentially competing species.
The calmodulin pathway and evolution of elongated beak morphology in Darwin's finches
Calmodulin (CaM), a molecule involved in mediating Ca2+ signalling, is expressed at higher levels in the long and pointed beaks of cactus finches than in more robust beak types of other species, which implicate the CaM-dependent pathway in the developmental regulation of craniofacial skeletal structures.
Comparative landscape genetics and the adaptive radiation of Darwin's finches: the role of peripheral isolation
The adaptive radiation of Darwin's finches has occurred in the presence of ongoing but low levels of gene flow caused by distance‐dependent interisland dispersal, concluding that Gene flow does not constrain phenotypic divergence, but may augment genetic variation and facilitate evolution due to natural selection.
Butterfly genome reveals promiscuous exchange of mimicry adaptations among species
It is inferred that closely related Heliconius species exchange protective colour-pattern genes promiscuously, implying that hybridization has an important role in adaptive radiation.
Nucleotide Variation, Linkage Disequilibrium and Founder-Facilitated Speciation in Wild Populations of the Zebra Finch (Taeniopygia guttata)
It is found that under a simple quantitative genetic model both drift and selection could have contributed to the observed divergence in six quantitative traits, and in both Australian and Lesser Sundas populations, diversity in Z-linked loci was significantly lower than in autosomal loci.
The allopatric phase of speciation: the sharp-beaked ground finch (Geospiza difficilis) on the Galápagos islands
The allopatric differentiation of six populations of the sharp-beaked ground finch, Geospiza difficilis, in the Galapagos archipelago is examined, asking how and why the populations became differentiated, and what the differences imply about speciation.
Variation in the size and shape of Darwin's finches
It is shown that the tree finches have relatively long legs (tarsi), and that these finches as well as the ground finches which spend most time scratching on the ground or climbing in cacti also have a relatively long hallux (hind toe).