Ecological Speciation in Crossbills

This paper, published in The American Naturalist by Julie Smith and Craig Benkman, is most intriguing. Unfortunately, it has a somewhat misleading title that has led others to trumpet it as discovery of a “new bird species in Idaho” (see here, here, and here).

The authors emphasize ecological speciation in a population of Red Crossbills in the South Hills of Idaho based on coevolution with lodgepine pine and reproductive isolation from two other crossbill populations that frequent the region. While this population may indeed be evolving away from parental-type Red Crossbills, but the authors fall short of formally describing it as a new species taxonomically distinct from the Red Crossbill; neither do they designate it as a new subspecies.