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Scientists: Chicks before eggs

研究表明先有雞后有蛋

British scientists have solved the ancient riddle of which came first - chicken or egg? The answer, they say, is the chicken. Researchers found that the formation of egg shells relies on a protein found only in a chicken's ovaries, according to The Sun of London. That means eggs have to be formed in chickens. The protein, called ovocledidin-17 (OC-17), speeds up the development of the shell.(See photo)

據(jù)英國《太陽報》報道，困擾人類的千古之謎"雞生蛋還是蛋生雞"終于有了答案。英國科學(xué)家稱：先有雞后有蛋。研究人員發(fā)現(xiàn)，蛋殼只有在一種蛋白質(zhì)的催化下才能形成，而這種物質(zhì)只存在于雞的卵巢內(nèi)。因此，一定是雞生蛋。這種名叫OC-17的蛋白質(zhì)能夠加速蛋殼的形成。(見圖)

*以上新聞由 ChinaDaily雙語手機(jī)報提供