DETERMINING HOMOLOGY OF MOLTS AND PLUMAGES TO ADDRESS EVOLUTIONARY QUESTIONS - A REJOINDER REGARDING EMBERIZID FINCHES

Determining how molt is integrated into the annual cycle, and understa nding what natural selection pressures have favored the diversity of m olt strategies in birds are important issues in ornithology and zoolog y in general. To study these issues, most ornithologists historically have used and continue to use many different nomenclatural systems whi ch tie names of molts and plumages (e.g., breeding plumage, summer plu mage, adult plumage) to events in the annual cycle, season or age. How ever, it is circular to study the evolution of molts and plumages in r elation to annual cycle events, seasons or age because the definitions of plumages and molts in these systems are defined in terms of these parameters. To study the evolution of molts and plumages it is essenti al to use a system such as that proposed by Humphrey and Parkes (1959, 1963) to identify homologous molts and plumages that is independent o f annual cycle events, seasons and age. This paper discusses how to us e correctly the Humphrey-Parkes system and illustrates this by discuss ing an example of how the Humphrey-Parkes system was applied incorrect ly in a series of studies on Passerina buntings. We also document that Phainopeplas, Phainopepla nitens, Yellow-breasted Chats, Icteria vire ns, Northern Cardinals, Cardinalis cardinalis, and Orange-breasted Bun tings, Passerina leclancherii exhibit a previously unknown sequence of molts and plumages that is homologous to that of other recently studi ed Passerina species, and suggest that this sequence of molts and plum ages probably is much more widespread in birds than is currently recog nized.