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380-million-year-old Gives Birth

机译：3.8亿岁的孩子出生

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摘要

Sex does not fossilize well. Until this year, the oldest evidence of copulation in higher animals came from 180-million-year-old fossils of fish giving birth. But in May paleontologists announced finding a pregnant fish 380 million years old at a dig in Western Australia, extending the history of so-called internal fertilization and live birth by 200 million years. A research team led by John Long, head of sciences at the Museum Victoria in Melbourne, unearthed the fish, a previously unknown species from an extinct group called the ptyctodonts. The skeleton of the fish, named Materpiscis, or "mother fish," contained the teeth, jaws, skull bones, and body plates of a much smaller member of the same species, as well as an umbilical cord connecting the two. Unlike the majority of fish alive today, which fertilize eggs after they have been laid, this one contained an embryo-unmistakable evidence of fertilization within the mother.
机译：性不能很好地僵化。直到今年，高等动物中交配的最古老证据来自有1.8亿年历史的鱼类生化石。但是在五月，古生物学家宣布在西澳大利亚州的一次挖掘中发现了一条有3.8亿年历史的怀孕鱼类，从而将所谓的内部受精和活产的历史延长了2亿年。由墨尔本维多利亚博物馆的科学负责人约翰·朗（John Long）领导的一个研究小组出土了这条鱼，这是一种来自灭绝物种的自称ty牙的先前未知的物种。这条鱼的骨骼名为Materpiscis，即“母鱼”，包含相同种类的小得多的成员的牙齿，颚，颅骨和身体板，以及连接两者的脐带。与今天活着的大多数鱼不同，它们在下蛋后就对卵进行受精，而其中的一条卵却清楚地表明了母亲体内受精的迹象。

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