The topic of hybridization (and hybrid plant foods) is often
discussed in raw circles, but usually without reference to
published research. The article whose abstract appears below,
discusses the role of hybridization in the evolution of
the sunflower. I strongly encourage list members who are
interested in the subject, to access the full text (in a good
library) and read the complete article.
Science, Vol. 301, Issue 5637, 1211-1216, August 29, 2003
"Major Ecological Transitions in Wild Sunflowers
Facilitated by Hybridization"
Loren H. Rieseberg, Olivier Raymond, David M. Rosenthal, Zhao Lai,
Kevin Livingstone, Takuya Nakazato, Jennifer L. Durphy,
Andrea E. Schwarzbach, Lisa A. Donovan, Christian Lexer
Abstract:
Hybridization is frequent in many organismal groups, but its role
in adaptation is poorly understood. In sunflowers, species found
in the most extreme habitats are ancient hybrids, and new gene
combinations generated by hybridization are speculated to have
contributed to ecological divergence. This possibility was tested
through phenotypic and genomic comparisons of ancient and synthetic
hybrids. Most trait differences in ancient hybrids could be
recreated by complementary gene action in synthetic hybrids and
were favored by selection. The same combinations of parental
chromosomal segments required to generate extreme phenotypes in
synthetic hybrids also occurred in ancient hybrids. Thus,
hybridization facilitated ecological divergence in sunflowers.
Tom Billings
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