Morphological, electrophoretic, and ecological analysis ofQuercus macrocarpapopulations in the Black Hills of South Dakota and Wyoming

摘要

Morphological data support the hypothesis that oak populations in the Black Hills of South Dakota and Wyoming reflect the effect of introgressive hybridization betweenQuercus macrocarpaandQ.gambelii; these populations cannot be electro-phoretically differentiated fromQ.macrocarpa. Thirteen populations of oaks were sampled in the Black Hills of South Dakota and Wyoming, and a single population each ofQ.macrocarpaandQ.gambeliiwere sampled outside of the Black Hills. Morphological data suggest significant similarities of populations located in northwestern Black Hills withQ.gambeliiand populations located in the eastern Black Hills withQ.macrocarpa. Disparity between morphological and electrophoretic data suggests that natural selection is operating differently on the morphological and isozymic characters.