Evolutionary Significance of Geographic Variation: Some Examples From Birds

Abstract

The study of geographic variation has probably taken up a well-known place in ornithology. For decades, most of researchers interested in evolutionary trends in birds focused on the study of geographic variation e.g. Morrison 1983, Zink 1986, Atwood 1988, Johnson and Marten 1992, Johnston 1994, Roselaar 1995, Engelmoer and Roselaar 1998, Johnson 2002 .