日前,,中國科學院古脊椎動物與古人類研究所的科學家們發(fā)現了一種與鳥類極具近親關 系 的 恐 龍——“胡 氏 耀 龍 ”,,“胡”源自我國已故的年輕古哺乳動物學家胡耀明。這種介于鳥類和恐龍之間的新物種將為揭開鳥類起源,、飛行起源及羽毛起源之謎等提供新的證據,。
這一研究結果將發(fā)表在今天出版的最新一期英國 《自然》(Nature)雜志上。
從10月25日起,,“胡氏耀龍”化石標本將在中國古動物館展出,。
“胡氏耀龍”生活在侏羅紀時期,身體全長超過40厘米,,屬于鳥翼類,,代表了和鳥類關系最為接近的恐龍之一。不同于其他已知恐龍,,“胡氏耀龍”長有4枚長約20多厘米的帶狀尾羽,。更有意思的是,它的其他羽毛均未形成為類似鳥類飛羽的構造,,雖然“胡氏耀龍”的前肢長于后肢,,形成了類似原始鳥類的前肢,但由于沒有飛羽,,“胡氏耀龍”并不具有飛行能力,。
“胡氏耀龍”的頭短而高,具有類似于恐龍中的竊蛋龍類頭骨的外形,。但與多數竊蛋龍不同的是,,它的上、下頜均具牙齒且前傾,。更有意思的是,,這些牙齒的大小出現了分化,形成了類似于一些哺乳動物的犬齒或門齒的咬合結構,。這在恐龍中是不常見的,。
在骨骼形態(tài)上,“胡氏耀龍”的一個明顯特征是尾椎極度退化,僅有16枚尾椎,,遠少于始祖鳥等,。
這項研究由中國科學院古脊椎動物與古人類研究所的張福成、周忠和,、徐星,、汪筱林和CorwinSullivan共同完成。(生物谷Bioon.com)
生物谷推薦原始出處:
Nature 455, 1105-1108 (23 October 2008) | doi:10.1038/nature07447
A bizarre Jurassic maniraptoran from China with elongate ribbon-like feathers
Fucheng Zhang1, Zhonghe Zhou1, Xing Xu1, Xiaolin Wang1 & Corwin Sullivan1
Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, China
Recent coelurosaurian discoveries have greatly enriched our knowledge of the transition from dinosaurs to birds, but all reported taxa close to this transition are from relatively well known coelurosaurian groups1, 2, 3. Here we report a new basal avialan, Epidexipteryx hui gen. et sp. nov., from the Middle to Late Jurassic of Inner Mongolia, China. This new species is characterized by an unexpected combination of characters seen in several different theropod groups, particularly the Oviraptorosauria. Phylogenetic analysis shows it to be the sister taxon to Epidendrosaurus 4, 5, forming a new clade at the base of Avialae6. Epidexipteryx also possesses two pairs of elongate ribbon-like tail feathers, and its limbs lack contour feathers for flight. This finding shows that a member of the avialan lineage experimented with integumentary ornamentation as early as the Middle to Late Jurassic, and provides further evidence relating to this aspect of the transition from non-avian theropods to birds.