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单词 Protoavis
释义

Protoavis

中文百科

原鸟属

原鸟属(属名:Protoavis)意为「第一种鸟类」,是种主龙类,化石发现于德州Post市附近的晚三叠纪地层。

古生物学家萨克·查特吉(Sankar Chatterjee)宣称这些化石属于一种原始的鸟类,如果属实,鸟类的起源将提早约7000万到6500万年。

鸟类演化专家劳伦斯·威特默(Lawrence Witmer)则认为原鸟并没有鸟类的特征,但具有虚骨龙类的特征。如果属实,原鸟将成为年代最早的虚骨龙类恐龙。

英语百科

Protoavis 原鸟属

The fossil of a bird-like animal on a black background. A foot, tail, and upper body are present. The head has a large beak while the arm bones are folded over to look like a bird's wings.

Protoavis (meaning "first bird") is a problematic taxon of archosaurian known from fragmentary remains from Late Triassic Norian stage deposits near Post, Texas. Much controversy remains over the animal, and there are many different interpretations of what Protoavis actually is. When it was first described, the fossils were described as being from a primitive bird which, if the identification is valid, would push back avian origins some 60-75 million years. The original describer of Protoavis texensis, Sankar Chatterjee of Texas Tech University, interpreted the type specimen to have come from a single animal, specifically a 35 cm tall bird that lived in what is now Texas, USA, around 210 million years ago. Though it existed far earlier than Archaeopteryx, its skeletal structure is allegedly more bird-like. Protoavis has been reconstructed as a carnivorous bird that had teeth on the tip of its jaws and eyes located at the front of the skull, suggesting a nocturnal or crepuscular lifestyle. Reconstructions usually depict it with feathers, as Chatterjee originally interpreted structures on the arm to be quill knobs, the attachment point for flight feathers found in some modern birds and non-avian dinosaurs. However, re-evaluation of the fossil material by subsequent authors such as Lawrence Witmer have been inconclusive regarding whether or not these structures are actual quill knobs.

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更新时间:2025/6/20 5:01:07