Based on properties of the rock attached to some of the fragments, Arbour and her colleagues think the specimen may date to about 70 million years ago in the Upper Cretaceous Period.

 
  • 基于附着在骨骼上碎石的特性,阿伯尔和她的同学们认为这一物种生活在0.;7亿年前白垩纪早期。
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