2月13日，中國科學院古脊椎動物與古人類研究所與福建省地質調查研究院聯合釋出最新研究成果：透過對福建省政和動物群發現的侏羅紀鳥類化石的研究，發現全球最古老的鳥類之一——“政和八閩鳥”（Baminornis zhenghensis），也是迄今唯一確切的侏羅紀鳥類，揭示了現代鳥類的體型結構在侏羅紀晚期（距今1.5億年）就已經出現。相關研究成果北京時間2月13日在《自然》發表。
A set of fossils discovered in East China's Fujian province has been identified as the only known unambiguous record of Jurassic birds, pushing back the origin of birds to the late Middle Jurassic period and rewriting the history of avian evolution.
Jurassic /dʒʊˈræsɪk/ 侏羅紀的
avian /ˈeɪviən/ 鳥（類）的
“政和八閩鳥”和“政和動物群”生態復原圖 圖源：新華社
我國發現全球
最古老鳥類——政和八閩鳥
該化石於2023年11月在政和大溪盆地發現，經過長達一年的室內修復和研究分析，研究團隊確定了該化石屬於鳥類，並將其命名為政和八閩鳥。其屬名“八閩”是福建的古稱。
After a year of restoration and research, a joint team from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences and the Fujian Institute of Geological Survey confirmed that the set of fossils discovered in November 2023 in Daxi village of Fujian's Zhenghe county belong to a bird from the late Middle Jurassic period.
中國科學院古脊椎動物與古人類研究所研究員、科學探索獎獲獎人王敏介紹， 根據一些體重的測算公式，能估算出八閩鳥的體重在150克左右，“和一些小型的鸚鵡大小比較相近 ”。
"After systematic research and comparison, the hypothesis was confirmed. The restored bird weighed over 150 grams, similar to a domesticated pet parrot," said Wang Min, a researcher from the CAS institute.
王敏介紹，在整個化石標本所在的政和動物群，還發現了一些生活在水裡或水邊的動物，比如像魚類、龜鱉類，“我認為這代表的是類似於沼澤的環境。”
The area of the fossil assemblage, characterized by swamps and wetlands, was home to a diverse array of species of fish, amphibians and reptiles, among others.
“政和八閩鳥”化石 圖源：央視新聞）
雖然化石不完整，但是它儲存了很多重要資訊。例如具有分離的肩胛骨和烏喙骨，腰帶骨骼顯現出很多進步的特徵。其中最重要、最特殊的地方就是具有癒合的尾綜骨，這是構成現代鳥類體型的基石。
Its fossils display a unique combination of features including birdlike shoulder and pelvic girdles as well as a hand structure resembling that of nonavian dinosaurs, according to the CAS.
What makes the Baminornis unique is that it has a short tail that consists of the pygostyle, which is a key feature of the modern bird body plan," Wang said.
鳥類和其他爬行動物最顯著的區別就是鳥類的尾巴很短，不但尾椎數目減少，而且最後幾枚尾椎（vertebrae）癒合成尾綜骨（pygostyle）結構，尾骨縮短是恐龍向鳥類演化中最徹底的形態變化之一。
One of the most significant differences between birds and reptiles is in their tails. Avian species have shorter tails with fewer tail vertebrae, and the last few vertebrae are fused into a structure called the pygostyle.
該發現將鳥類起源時間
推至中侏羅晚期
據瞭解，目前全世界最古老的鳥類，比較公認的是德國發現的始祖鳥（The Archaeopteryx），它發現在侏羅紀時期，距今大概1.5億年。然而始祖鳥的分類位置近期受到質疑，部分研究認為始祖鳥屬於恐爪龍類，而非鳥類。
The Archaeopteryx, the fossils of which were first discovered around 1860, belonged to the Late Jurassic period and was once considered the earliest bird. However, its long tail and primitive features led some scientists to question its classification as a bird. Instead, they suggested that it belonged to a group of bird-like dinosaurs.
“政和八閩鳥”的發現首次揭示了現代鳥類的體型在侏羅紀就已經出現，並將鳥類起源時間推至中侏羅晚期，大約1.72億至1.64億年前，是目前最確切的且唯一的侏羅紀鳥類，極大地豐富了人類對鳥類進化歷史的認識。
除了八閩鳥化石之外，王敏帶領的研究團隊還發現了一個單獨儲存的叉骨（furcula）。初步的研究結果顯示，該叉骨明顯區別於政和八閩鳥，與出現於1.3億年前白堊紀的今鳥型類非常相似。這一發現證實，至少兩種鳥類生活在政和動物群，如果未來能證實該叉骨的確屬於今鳥型類，那麼鳥類起源的時間將會進一步提前。
The discovery of this furcula confirms that at least two species of birds lived in the Zhenghe Fauna. If the furcula indeed belongs to the ornithuromorpha, the origin of birds would be pushed back even further.
記者：閆東潔 胡美東
實習生：林朝陽
來源：央視新聞 新華社 中國日報
推 薦 閱 讀