Photo: a lancelet, a close relative of vertebrates, in several stages of decay. credit: University of Leicester.

图片：脊椎动物的近亲，一只文昌鱼腐烂过程的几个阶段。

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Photo: a lancelet, a close relative of vertebrates, in several stages of decay. credit: University of Leicester.

图片：脊椎动物的近亲，一只文昌鱼腐烂过程的几个阶段。

youdao