On the evolutionary history of Ephedra: Cretaceous fossils and extant molecules
نویسندگان
چکیده
منابع مشابه
On the evolutionary history of Ephedra: Cretaceous fossils and extant molecules.
Gnetales comprise three unusual genera of seed plants, Ephedra, Gnetum, and Welwitschia. Their extraordinary morphological diversity suggests that they are survivors of an ancient, more diverse group. Gnetalean antiquity is also supported by fossil data. Dispersed "ephedroid" (polyplicate) pollen first appeared in the Permian >250 million years ago (Myr), and a few megafossils document the pres...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2004
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.0407588101