Double Fertilization in Gnetales: Implications for Understanding Reproductive Diversification among Seed Plants

@article{Friedman1996DoubleFI,
  title={Double Fertilization in Gnetales: Implications for Understanding Reproductive Diversification among Seed Plants},
  author={William E Friedman and Jeffrey S. Carmichael},
  journal={International Journal of Plant Sciences},
  year={1996},
  volume={157},
  pages={S77 - S94}
}
The coupled processes of double fertilization and postfertilization endosperm formation have long been viewed as important and synapomorphic features of flowering plants. Recent developmental studies of fertilization in the nonflowering seed plants Ephedra and Gnetum clearly document a regular process of double fertilization. The condition for Welwitschia remains unknown. Unlike angiosperms, the product of the second fertilization event in Ephedra and Gnetum is diploid and expresses the… Expand
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Development and evolution of the female gametophyte and fertilization process in Welwitschia mirabilis (Welwitschiaceae).
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  • 2015
TLDR
An analysis of character evolution indicates that the female gametophyte of Welwitschia is highly apomorphic both among seed plants, and specifically within Gnetales, but also shares several key synapomorphies with its sister taxon Gnetum. Expand
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  • Biology, Medicine
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  • 2001
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It is demonstrated how the new phylogenetic hypotheses for seed plants and angiosperms can significantly alter previous interpretations of evolutionary homology and firmly entrenched assumptions about what is synapomorphic of flowering plants. Expand
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  • Biology, Medicine
  • Proceedings of the National Academy of Sciences
  • 2008
TLDR
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TLDR
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