Interspecific gene flow in sympatric oaks.

摘要: Abstract Variation of chloroplast DNA and nuclear ribosomal (DNA encoding RNA) was studied for five species white oak native to the eastern United States. Although these differ in many morphological characters have different (though overlapping) geographical ranges ecological tolerances, they are interfertile often grow mixed stands, hybrids occasionally found nature. All individuals were morphologically typical members their respective species-i.e., showed no evidence recent hybrid ancestry. Restriction site markers reveal several clear cases localized gene exchange between species, showing that there is appreciable flow sympatric this group. One length variant DNA, however, specific. The sharp differences together with one variant, suggest genes may be exchanged less freely than genotypes.