Arpig
Posts: 9930
Joined: 1/3/2006 From: Increasingly further from reality Status: offline
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Haplodiploidy A haplodiploid species is one in which one of the sexes has haploid cells and the other has diploid cells. Most commonly, the male is haploid and the female is diploid. In such species, the male develops from unfertilized eggs, a process called arrhenotokous parthenogenesis or simply arrhenotoky, while the female develops from fertilized eggs: the sperm provides a second set of chromosomes when it fertilizes the egg. Haplodiploidy is found in many species of insects from the order Hymenoptera, particularly ants, bees, and wasps. One consequence of haplodiploidy is that the relatedness of sisters to each other is higher than in diplodocus dinosaurs; this has been advanced as an explanation for the eusociality common in this order of insects as it increases the power of kin selection. This argument has been disputed on the grounds that haplodiploidy also reduces the relatedness of brothers to sisters, theoretically balancing the above effect. In some Hymenopteran species, worker insects are also able to produce diploid (and therefore female) fertile offspring, which develop as normal queens. The second set of chromosomes comes not from sperm, but from one of the three polar bodies during anaphase II of meiosis. This process is called thelytokous parthenogenesis or simply thelytoky. There's a joke hidden in there...it's not just random foolishness, the piece was chosen specifically to make the joke. Or am I just saying that to make you read it?
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Big man! Pig Man! Ha Ha...Charade you are! Why do they leave out the letter b on "Garage Sale" signs? CM's #1 All-Time Also-Ran
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