Fig. 2
From: Diversifying Coevolution between Crossbills and Conifers
Crossbills vary greatly in bill and body size. This shows the extremes in the variation in bill size, with the Parrot Crossbill (Loxia pytyopsittacus; top), the largest crossbill, and the Common Crossbill, Loxia curvirostra himalayensis (bottom; sensu Edelaar 2008), from the Himalayan Mountains the smallest. There are at least 12 distinct taxa of crossbills in the New World and probably up to 20 in the Old World (photo: Pim Edelaar)