Birder's Guide

NOV 2013

Birder's Guide is the American Birding Association's newest publication. Each issue focuses on a key subject, providing tips from experienced birders on a wide variety of topics like Travel, Listing & Taxonomy, Gear, and Conservation & Community.

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Oriolidae. (Evolutionarily, the original orioles are not that far removed from our familiar jays and crows.) On the other hand, foraging strategy and DNA unite "our" colorful New World orioles with their more monochromatic relatives, the New World blackbirds, grackles, and cowbirds. All together, they are all referred to as icterids. The icterids were often classifed with other groups that employ gaping as a foraging strategy (including the starlings), but there is now no question that the icterids belong with the other nine-primaried oscines, with perhaps the wood-warblers or Yellow-breasted Chat being their nearest relatives. And, as with the wood-warblers, it appears we have a pretty good idea about which birds are icterids and which are not: this group has not seen a lot of its members moved to and from other groups. This is not the case with the remaining groupings. "Just because we're brown and streaky doesn't mean we're all related." The nine-primaried oscines with bills adapted for eating seeds have been among the most diffcult to classify. As is the case throughout the animal kingdom, evolutionary convergence masks true relationships because similar morphology often evolves in response to similar lifestyles and foraging strategies. In the case of all the world's species referred to as sparrow, bunting, or seedeater, a similar bill shape and function has evolved several times along unrelated branches of the passerines. The longspurs (and Snow and McKay's buntings) were long thought to be most closely related to the Old World (original) buntings and the New World sparrows. Evidence shows that the longspurs are not particularly closely related to most of the nine-primaried oscines, and they are now placed in their own family (Calcariidae), perhaps located on an evolutionary branch between the Olive Warbler and the rest of the emberizids (Klicka et al. 2003, AOU 2010). The buntings of the Old World genus Emberiza are prized for their rarity in North America, and this genus gives its name to the family Emberizidae. It has long been believed that these buntings are most closely related to the New World sparrows and towhees. Again, this may not be true, and although the AOU retains Emberiza in the same family with the New World sparrows, don't be surprised if they are moved sometime soon. Longspurs, including Smith's Longpsur (opposite page, above left, © Michael L. P. Retter) and buntings of the genus Emberiza, like this Little Bunting (opposite page, below left, © Rafael Armada), are rather similar in plumage and morphology to the New World Sparrows (represented below by a White-throated Sparrow, © Tara Tanaka). Molecular studies, however, place these groups much further apart in taxonomic space. November 2013 | Birder's Guide to Listing & Taxonomy 17

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