The Great Plains Hybrid Zones

摘要: About 130 taxa of birds reach distributional limits in the central Great Plains, and 28 these are replaced there by closely related that apparently their ecological counterparts. In many cases, it is reasonable to assume presence a similar, competing form factor limiting distribution. Hybridization between counterparts known occur at least occasionally 22 (11 pairs taxa) (14 pairs) taxa, commonly hybridizing common Plains. terms numbers individuals they comprise sizable proportion bird life region. Although species specialized live grasslands numerous only two, Eastern Western meadowlarks (Sturneila magna S. negiecta), hybridize The other adapted deciduous thicket or woodland edge habitats. For most part, an eastern taxon hybridizes with western taxon, but some examples replacement northeast-southwest, one case north-south. east-west replacements, counterpart seemingly differentiated allopatry during Pleistocene presently secondary contact (Short, 1965; Remington, 1968; Mengel, 1970).