Homologous Versus Antithetic Alternation of Generations and the Origin of Sporophytes

  title={Homologous Versus Antithetic Alternation of Generations and the Origin of Sporophytes},
  author={David Haig},
  journal={The Botanical Review},
  • D. Haig
  • Published 26 July 2008
  • Biology
  • The Botanical Review
The late-nineteenth/early-twentieth century debate over homologous versus antithetic alternation of generations is reviewed. Supporters of both theories, at first, used Coleochaete as a model for the origin of land-plant life cycles. The early debate focused on the morphological interpretation of the sporophyte and on whether vascular cryptogams had bryophyte-like ancestors. The terms of the debate shifted after the discovery that the alternation of morphological generations was accompanied by… 

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