Sometimes we lose numbers on our life lists when the American Ornithological Society’s Committee on Classification and Nomenclature (informally known as the Checklist Committee) delivers its annual bird-name update. Sometimes we gain new ones. And sometimes a familiar species winds up with a new name or is classified in a different family. This year’s report from the AOS Checklist Committee was published on June 24. Only a few of its changes, which are decided by a panel of leading experts, will be of direct interest to birders—but this gives us a good opportunity to talk about the reasons behind the decisions. Blue-throated Hummingbird gets upgraded to the Blue-throated Mountain-gem. The hummingbird family is incredibly diverse with more than 350 species in tropical regions. To give them distinctive names, scientists have combined imagination with poetry. On a list of South American birds we see sunangels, sungems, sunbeams, hillstars, woodstars, starfrontlets...