Islands are natural laboratories for studying patterns and processes of evolution. Research on island endemic birds has revealed elevated speciation rates and rapid phenotypic evolution in several groups (e.g. white-eyes, Darwin’s finches). However, understanding the evolutionary processes behind these patterns requires an understanding of how genotypes map to novel phenotypes. To date, there are few high-quality reference genomes for species found on islands. Here, we sequence the genome of one of Ernst Mayr’s “great speciators,” the collared kingfisher (Todiramphus chloris collaris). Utilizing high molecular weight DNA and linked-read sequencing technology, we assembled a draft high-quality genome with highly contiguous scaffolds (scaffold N50 = 19 Mb). Based on universal single-copy orthologs, we estimated a gene space completeness of 96.6% for the draft genome assembly. The population demographic history analyses reveal a distinct pattern of contraction and expansion in population size throughout the Pleistocene. Comparative genomic analysis of gene family evolution revealed that species-specific and rapidly expanding gene families in the collared kingfisher (relative to other Coraciiformes) are mainly involved in the ErbB signaling pathway and focal adhesion. Todiramphus kingfishers are a species-rich group that has become a focus of speciation research. This draft genome will be a platform for future taxonomic, phylogeographic, and speciation research in the group. For example, target genes will enable testing of changes in sensory structures associated with changes in vision and taste genes across kingfishers.
Understanding the genetic basis of convergence at broad phylogenetic scales remains a key challenge in biology. Kingfishers (Aves: Alcedinidae) are a cosmopolitan avian radiation with diverse colors, diets, and feeding behaviors—including the archetypal plunge-dive into water. Given the sensory and locomotor challenges associated with air-water transitions, kingfishers offer a powerful opportunity to explore the effects of convergent behaviors on the evolution of genomes and phenotypes, as well as direct comparisons between continental and island lineages. Here, we use whole-genome sequencing of 30 diverse kingfisher species to identify the genomic signatures associated with convergent feeding behaviors. We show that species with smaller ranges (i.e., on islands) have experienced stronger demographic fluctuations than those on continents, and that these differences have influenced the dynamics of molecular evolution. Comparative genomic analyses reveal positive selection and genomic convergence in brain and dietary genes in plunge-divers. These findings enhance our understanding of the connections between genotype and phenotype in a diverse avian radiation.
more » « less- Award ID(s):
- 2112468
- PAR ID:
- 10470560
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Communications Biology
- Volume:
- 6
- Issue:
- 1
- ISSN:
- 2399-3642
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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