alternation of generations

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  • noun

Synonyms for alternation of generations

the alternation of two or more different forms in the life cycle of a plant or animal

References in periodicals archive ?
One question, left unanswered by Hofmeister, was how the alternation of generations of the 'higher cryptogams' or archegoniates related to the life histories of 'lower cryptogams' or thallophytes.
The ensuing debate focused on the origin of the asexual generation of land plants (i.e., the sporophyte) and is conventionally characterized as a conflict between theories of antithetic and homologous alternation of generations. This debate initially took place in the context of a common belief in the direct inheritance of form.
Celakovsky's (1874) purpose was to present an accurate classification of the alternation of generations (Generationswechsel).
Pringsheim (1876b) presented a contrary interpretation of the connection between alternation of generations in thallophytes and mosses.
Bower (1890) viewed the alternation of generations of archegoniates as arising from the adaptation of an initially aquatic organism for the land.
Brown (1935: 657-658) clearly believed, however, that "it is doubtful if any alternation of generations ...
Various arguments, based on evidence (real or supposed), have been laid down in favor of either the homologous theory or the antithetic theory of alternation of generations; that is, of land-plant sporophyte origins.
An argument often put forward in favor of the homologous theory of alternation of generations (and sporophyte origin) is the alleged "evidence" of algae with isomorphic (morphologically identical or very similar) gametophytes and sporophytes, such as Ulva, Cladophora suhriana, Chaetomorpha (cf.
246) presented an easy-to-follow "flow diagram" of the evolution of meiosis, life cycles, alternation of generations, and so forth; their tracings led first to eukaryotes (after the development of mitosis and meiosis), and then to several major eukaryotic lineages and sublineages, including land plants based on the timing of meiosis in the life cycle and the supposed development of alternating generations.
South and Whittick (1987) rightly saw land plants as possessing sporic meiosis (since they do!) but envisioned this lineage as arising from ancestors with preexisting alternation of generations, for which there is no substantive evidence (only speculation), as I have discussed and will continue to discuss.
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