Hybridizing Buntings in Iran

Ornithologists like to explore new territory, searching for other species to study or new questions to answer. But occasionally, it makes sense to revisit an old area and examine it again with new methods. This is exactly what Ali Golamhosseini (Shiraz University, Iran) and his colleagues did. They revisited a hybrid zone between Black-headed Bunting (Emberiza melanocephala) and Red-headed Bunting (E. bruniceps) in northern Iran that has been studied by Paludan (1940) and Haffer (1970).

Black-headed Bunting (from Wikipedia.org)

Compared to these two studies, the hybrid zone has expanded westward by approximately 170 km. To find out what caused this expansion, the authors applied Species Distribution Models (SDM). These models can disentangle the importance of intrinsic (e.g., competition between species) and extrinsic (e.g., climate) factors in shaping the observed species distribution.

Red-headed Bunting (from mangoverde.com)

The results from the SDM show a mismatch between the potential and realized distribution of the species. From a climatic point of view, the Black-headed Bunting could occur farther to the east, but it doesn’t. Probably, it is out-competed by the Red-headed Bunting which might be expanding westward due to land use changes by humans (i.e. deforestation and extension of agriculture).

I wonder what this hybrid zone will look like after another 70 years…

References

Gholamhosseini, A., Aliabadian, M., Darvish, J., Töpfer, T. & Sætre, G.-P. (2017). An Expanding Hybrid Zone between Black-Headed and Red-Headed Buntings in Northern Iran. Ardea 105, 27-36.

Haffer, J. (1977). Secondary contact zones of birds in northern Iran. Zoologisches Forschungsinstitut und Museum Alexander Koenig.

Paludan, K. (1940). Contributions to the ornithology of Iran. Ejnar Munksgaard.

 

This paper has been added to the Emberizidae page.

Rawnsley’s Bowerdbird: Another species that turns out to be a hybrid

On 14 July 1867, Henry Charles Rawnsley shot a bowerbird at his house near Brisbane, Queensland (Australia). That unfortunate specimen was later used to describe a new species: the Rawnsley’s Bowerbird (Ptilonorhynchus rawnsleyi, it is a bit ironic that a new species is named after its killer). Here is a drawing of the bird:

A review of this specimen led to the conclusion that it was a hybrid between Regent Bowerbird (Sericulus chrysocephalus) and Satin Bowerbird (Ptilonorhynchus violaceus). Recently, a second specimen of this ‘species’ has been observed at Beechmont. The pictures taken there show a striking resemblance with the drawings from the 1800s.

Recent picture of the Rawnsley’s Bowerbird (from http://www.bellingencourier.com.au)

It is not the first time that a hybrid specimen has been classified as a new species. Other notorious examples include Argus bare-eye (Phlegopsis barringeri),  Imperial Pheasant (Lophura imperialis) , Brewster’s Warbler (Vermivora leucobronchialis) and Lawrence’s Warbler (V. lawrencei). I wrote about these ‘species’ on my other blog: Evolutionary Stories. See here and here.

 

References

Frith, C. B. 2006. A history and reassessment of the unique but missing specimen of Rawnsley’s Bowerbird Ptilonorhynchus rawnsleyi, Diggles 1867,(Aves: Ptilonorhynchidae). Historical Biology, 18: 57-68.

Frith, C. B. 2016. A second living’Rawnsley’s Bowerbird’-a wild adult male hybrid from a Regent Bowerbird’Sericulus chrysocephalus’ Satin Bowerbird’Ptilonorhynchus violaceus’ cross. Australian Field Ornithology, 33: 14.

 

Many thanks to Clifford Frith for providing me with the original 2016 paper. The papers have been added to the page of Ptilonorhynchidae family.