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来源：雅诚德英语网
The abundance of feathered fossils has allowed paleontologists to examine a fundamental question: Why did feathers evolve?
丰沛的羽毛化石使得古生物学家有条件来验证一个最基本的问题：为什么羽毛会进化？
The abundance of feathered fossils has allowed paleontologists to examine a fundamental question: Why did feathers evolve?
丰沛的羽毛化石使得古生物学家有条件来验证一个最基本的问题：为什么羽毛会进化？