(M.Sc. in Reproductive Physiology, in case you wondered).
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Yay...some useful expertise. In this situation, can you explain how two identical maternal haploids arose - I’m assuming from what originally was a single haploid. I asked another poster who seemed that he/she might have some expertise but that poster preferred to play “cute” instead of answering.
Thanks.
Actually, from the article itself, the ovum actually split three ways. The problem with polyspermy is that you get a polyploid situation in the ovum, which has to be evened out during the division cycles, or the resultant daughter cells quickly become non-viable (you can see polyploidy in some plants, which can adapt to tetraploid, and hexaploid situations, but animal cells generally cannot). What happened was that the fertilised ovum split into two daughter cells, each with maternal haploid chromosomes matched up to paternal haploid, as is normal, although the paternal chromosomes themselves were a mix n’ match from each of the two sperm. Still The two normal maternal haploid (from the first mitosis event) matched up to the normal compliment of paternal haploid formed paternal chromosomal chimeras, but still, everything was hunky-dory. There was also an extra mitotic event, where the two ‘odd’ sets of paternal haploid chromosomes were forced to match with each other, and this third cell quickly became non-viable.
Best I can answer it, and still keep it in reasonably layman’s terms. Not sure if that helps.