The end of 2016 has been quite hectic for me as I successfully defended my PhD thesis (read a report of that day here). So, I took some well-deserved holidays. But at the start of 2017, I felt the urge to update the Avian Hybrids Project. Here is an overview of some recent papers.
(House Sparrow x Spanish Sparrow)^2
In Northern Africa, House Sparrow and Spanish Sparrow also interbreed (Summers‐Smith & Vernon, 1972). In Algeria, House Sparrows and hybrids mainly reside in urban areas, while Spanish Sparrows live in cultivated areas. The latter also breed later and raise only two clutches (House Sparrows and hybrids raise three clutches). The mitogenome of the House Sparrow has almost completed introgressed into the Italian Sparrow (see above). In Algeria, however, a small percentage of the hybrids has a Spanish haplotype (Belkacem et al., 2016).
Belkacem, A. A., Gast, O., Stuckas, H., Canal, D., LoValvo, M., Giacalone, G. & Packert, M. (2016). North African hybrid sparrows (Passer domesticus, P. hispaniolensis) back from oblivion – ecological segregation and asymmetric mitochondrial introgression between parental species. Ecology and Evolution 6, 5190-5206.
Lord of the Rings
The Short-tailed Albatross (Phoebastria albatrus) is a vulnerable seabird that mainly breeds on Torishima and the Senkaku Islands in the Pacific Ocean. The two populations are genetically distinct and display assortative mating. However, a study based on mate choice of ringed (from Torishima) and unringed birds (from the Senkaku Islands) revealed some mixed pairings, indicating that pre-mating isolation is incomplete (Eda et al., 2016).
Eda, M., Izumi, H., Konno, S., Konno, M. & Sato, F. (2016). Assortative mating in two populations of Short‐tailed Albatross Phoebastria albatrus on Torishima. Ibis 158, 868-875.
The Mangrove Finch (Camarhynchus heliobates) is critically endangered and currently restricted to one small population on Isabela Island (Galapagos Islands). A genetic study found that a number of individuals have hybridized with the closely related Woodpecker Finch (C. pallidus). Possibly, there is a breakdown of reproductive isolation between these species because the Mangrove Finches cannot find a mate due to the low population size (Lawson et al., 2016).
Lawson, L. P., Fessl, B., Vargas, F. H., Farrington, H. L., Cunninghame, H. F., Mueller, J. C., Nemeth, E., Sevilla, P. C. & Petren, K. (2016). Slow motion extinction: inbreeding, introgression, and loss in the critically endangered mangrove finch (Camarhynchus heliobates). Conservation Genetics, 1-12.
A genomic analysis of a contact zone between two divergence lineages of the Brown Creeper (Certhia americana) in the Madrean Archipelago sky islands (Arizona, USA) reported complete allopatry during the breeding season and no gene flow (Manthey, Robbins & Moyle, 2016).
Manthey, J. D., Robbins, M. B. & Moyle, R. G. (2016). A genomic investigation of the putative contact zone between divergent Brown Creeper (Certhia americana) lineages: chromosomal patterns of genetic differentiation. Genome 59, 115-25.
Keep an eye on the website, more updates will follow soon!