A new genetic study led by evolutionary biologist Glenn-Peter Saetre from the University of Oslo has come up with conclusive genetic evidence that sparrows recently evolved a third species. This is the Italian sparrow (Passer italiae)
The researchers studied populations of Italian and Spanish sparrows (P. hispaniolensis), that share the same habitat in the south-east of Italy.
The Italian sparrow, the researchers say is a cross between house sparrow (P. domesticus) and the Spanish sparrow.
Those species that, under natural conditions, tend not to interbreed comes under the definition of a distinct species. The Italian sparrow is not reproducing with the Spanish sparrow. The Italian sparrow possesses mitochondrial (mt) DNA haplotypes identical to both putative parental species (although mostly of house sparrow type), indicating a recent hybrid origin. Geographic and reproductive barriers restrict gene flow into the nascent hybrid species. According to the researchers they will gradually, generation by generation, become even more genetically distinct.
Journal reference
Hybrid speciation in sparrows I: phenotypic intermediacy, genetic admixture and barriers to gene flow
JO S. HERMANSEN, STEIN A. SÆTHER, TORE O. ELGVIN, THOMAS BORGE, ELIN HJELLE.
Molecular Ecology
Volume 20, Issue 18, pages 3812–3822, September 2011
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