Hello Daniel,
Sunday, December 02, 2001, 3:20:54 PM, you wrote:
Rac> How does parthengensis evolve in a species, and what is mechainism (if that's
Rac> the right term) for egg division?
Most parthenogenetic species are of hybrid origin. I don't think
anyone knows for sure what cytogenetic mechanisms are involved but
inheritance is clonal. It's thought that the hybridization alters
cell division during gamete formation. In Cnemidophorus uniparens,
premeiotic mitosis lacks nuclear division and cytokinesis resulting in
a tetraploid cell (oogonium). This cell then goes through meiosis and
produces a diploid gamete (since meiosis halves the cell's karyotype).
How this cell initiates development is also unknown.
Pretty weird stuff.
--
Best Regards Reply To: [EMAIL PROTECTED]
Tony Gamble
University of Minnesota
Department of Fisheries, Wildlife, and Conservation Biology
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