Oophagy
From Wikipedia, the free encyclopedia
Oophagy (egg eating) is the practice of embryos feeding on eggs produced by the ovary while still inside the mother's uterus.
</div>Oophagy is thought to occur in all sharks in the order Lamniformes and has been recorded in the bigeye thresher (Alopias superciliosus), the pelagic thresher (A. pelagicus), the shortfin mako (Isurus oxyrinchus) and the porbeagle (Lamna nasus) among others.<ref name="EFMT">Christina L. Conrath. Elasmobranch Fisheries Management Techniques Chapter 7. Retrieved on 03 Aug 2006.</ref>
This practice may lead to larger embryos or prepare it for a predatory lifestyle.<ref>Wourms, J.P. (1981) Viviparity: The maternal-fetal relationship in fishes. Am. Zool. 21:473-515.</ref>
There are variations in the extent of oophagy among the different shark species. The grey nurse shark (Carcharias taurus) practices intrauterine cannibalism, the first developed embryo consuming both additional eggs and any other developing embryos. Slender smoothhounds (Gollum attenuatus), form egg capsules which contain 30-80 ova within which only one ovum develops while all other ova are ingested and packed to an external yolk sac. The embryo then develops normally without ingesting further eggs.<ref name="EFMT" />
Oophagy is also used to refer to more general egg-eating behaviours such as those practiced by some snakes or the differential oophagy practiced by the Polistes biglumis species of wasp.
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