Chapter 13: Alaska Song Sparrows (Melospiza Melodia) Demonstrate that Genetic Marker and Method of Analysis Matter in Subspecies Assessments

Abstract

w e examined genetic and morphological characteristics of the Song Sparrows (Melospiza melodia) of northwestern North America, which have a relatively large number of phe- notypically described subspecies (n = 6 in this region). mitochondrial DNA (mtDNA) sequences showed little information about these subspecies, with no reciprocal monophyly evident. however, differences in body mass and microsatellite allele frequencies supported continued recognition of subspecific units for taxonomy and conservation. Song Sparrow subspecies in this region are probably representative of many recently diverged populations that have not been isolated long enough for complete lineage sorting using mtDNA markers, yet which have evolved differences that are likely to be genetically based. we emphasize the importance of using multiple lines of evidence, genetic and morphological, in assessing subspecific status, lest we overlook important biological diversity that has accrued below the level of full species.