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Islands have long represented natural laboratories for studying many aspects of ecology and evolutionary biology, from speciation to community assembly. One aspect that has been well documented is the correlation between island size and taxonomic diversity, likely due to decreased complexity and population size on small islands. This same logic can apply to genetic diversity, which should predictably decrease with effective population size. The island size–diversity correlation has received support over the years but often focuses on single metrics of genetic diversity. Here, we useZosteropswhite-eyes in the Solomon Islands to study the correlation between island size and various metrics related to genetic diversity, including runs of homozygosity and fixation of transposable elements. We find that almost all these metrics strongly correlate with island size, and in turn with each other. We infer that island size is independently correlated with these different variables, demonstrating that population size impacts genomic metrics of diversity in a variety of ways across temporal and hierarchical scales.
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This content will become publicly available on January 1, 2026
Genomic data reveal that the Cuban blue-headed quail-dove ( Starnoenas cyanocephala ) is a biogeographic relict
Islands are well known for their unique biodiversity and significance in evolutionary and ecological studies. Nevertheless, the extinction of island species accounts for most human-caused extinctions in recent time scales, which have accelerated in recent centuries. Pigeons and doves (Columbidae) are noteworthy for the high number of island endemics, as well as for the risks those species have faced since human arrival. On Caribbean islands, no other columbid has generated more phylogenetic interest and uncertainty than the blue-headed quail-dove,Starnoenas cyanocephala. This endangered Cuban endemic has been considered more similar, both behaviourally and phenotypically, to Australasian species than to the geographically closer ‘quail-dove’ (Geotrygons.l.) species of the Western Hemisphere. Here, we use whole genome sequencing fromStarnoenasand other newly sequenced columbids in combination with sequence data from previous publications to investigate its relationships. Phylogenomic analyses, which represent 35 of the 51 genera currently comprising the Columbidae, reveal that the blue-headed quail-dove is the sole representative of a lineage diverging early in the radiation of columbids.Starnoenasis sister to the species-rich subfamily Columbinae, which is found worldwide. As a highly distinctive evolutionary lineage lacking close modern relatives, we recommend elevating the conservation priority ofStarnoenas.
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- PAR ID:
- 10568064
- Publisher / Repository:
- Royal Society
- Date Published:
- Journal Name:
- Biology Letters
- Volume:
- 21
- Issue:
- 1
- ISSN:
- 1744-957X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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