Quote:
Originally Posted by tilia
Is pregnant before it's born.
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Aphid
Most aphids are born pregnant and beget females without wastrel males. These parthenogenetic oocytes result from a modified meiosis that skips the reduction division, maintaining diploidy and heterozygosity. Embryos complete development within the mother’s ovary one after another, in assembly line fashion. These developing embryos contain developing embryos of the third generation within them, like Russian dolls.
Once a year, most aphids quit this hectic lifestyle and have sex. In temperate regions, autumnal conditions induce sexual forms. Sexual females look superficially like asexual females, but their ovaries produce eggs, rather than embryos. Males are produced by another trick of asexual meiosis leading to loss of one X chromosome.
Spineless but intelligent.