Two recent studies describe new hybrid combinations.
Most scientific papers on avian hybridization try to answer particular questions. How often do these two species interbreed? Are the hybrids able to reproduce? Has there been introgression? But before you can start answering such questions, you need to know which species are hybridizing. So, it is important to describe newly discovered hybrids. And two recent studies do just that.
A Hybrid Ibis?
Let’s start by travelling to Australia. In the state of New South Wales, Corey Callaghan and his colleagues observed a possible hybrid between Australian White Ibis (Threskiornis moluccus) and Straw-necked Ibis (T. spinicollis). The plumage of this bird showed characteristics of both putative parental species. It is not the first time that this particular hybrid has been reported. In 1983, Disher described a similar bird, although he also considered the possibility that it was a bird with aberrant plumage. So, to be absolutely sure about the identity of this peculiar bird DNA analysis is probably necessary.
A Bizarre Brush finch
Now we cross the Pacific Ocean to pay a visit to South America, Colombia to be precise. Here, in the foothills of the Andes, Diego Carantón‑Ayala and his colleagues found a strange specimen of Brush-finch (genus Atlapetes). Was it a hybrid or an aberrant individual from a local species? To figure this out, the researchers applied several morphological and genetic analyses.
The genetic data suggested that it is a hybrid between White-naped Brush finch (Atlapetes albinucha) and Dusky-headed Brush finch (Atlapetes fuscoolivaceus). The mitochondrial DNA of the hybrid, which is only transmitted through the female lineage, clustered with Dusky-headed Brush finch, indicating that this was the female parent. The nuclear DNA, on the other hand, pointed to White-naped Brush finch as the father. The morphological characteristics of the hybrid were in line with this conclusion.
Callaghan C., Ryall S. & Kingsford R. (2017) A probable Australian White Ibis Threskiornis moluccus × Straw-necked Ibis T. spinicollis hybrid. Australian Field Ornithology 34, 47-48.
Carantón‑Ayala D., Avendaño J.E., Cadena, C.D. (2018) Hybridization in brushfinches (Atlapetes , Emberizidae) from the southeast Andes of Colombia: a consequence of habitat disturbance? Journal of Ornithology
Disher, P. (1983). An unusual ibis. Bird Observer 620, 77.