PHYLOGENY OF TITMICE (PARIDAE) .1. ESTIMATE OF RELATIONSHIPS AMONG SUBGENERA BASED ON DNA-DNA HYBRIDIZATION

The phylogenetic relationships of titmice and chickadees (Passeriforme s: Paridae) were estimated by DNA-DNA hybridization. Fifteen species o f parids (representing all six subgenera) and two outgroups, Penduline Tit Remit pendulinus and White-breasted Nuthatch Sitta carolinensis, were radiolabeled and compared pairwise to produce a complete reciproc al set of distance measures. The resulting phylogeny supported the tra ditional allocation of species to subgenera, except that Parus woollwe beri clustered with the North American crested tits (subgenus Baeoloph us) rather than the Old World crested tits (Lophophanes). The interrel ationships of most subgenera remained unresolved. Nevertheless, a majo r subdivision in the family was strongly indicated: i.e., the great ti ts (subgenus Par us) and the blue tits (subgenus Cyanistes) formed a c lade that is the sister taxon of the rest of the family. This bifurcat ion has important ecological, physiological, and morphological ramific ations, as it correlates exactly with seed-caching and flocking habits , hippocampal development, and leg-muscle character distributions. The se DNA-hybridization results corroborate or complement the phylogeneti c relationships among parids supported by other molecular data sets (v iz., allozyme, restriction site, and preliminary DNA hybridization ana lyses).