日前,中国科学院古脊椎动物与古人类研究所的科学家们发现了一种与鸟类极具近亲关 系 的 恐 龙——“胡 氏 耀 龙 ”,“胡”源自我国已故的年轻古哺乳动物学家胡耀明。这种介于鸟类和恐龙之间的新物种将为揭开鸟类起源、飞行起源及羽毛起源之谜等提供新的证据。
这一研究结果将发表在今天出版的最新一期英国 《自然》(Nature)杂志上。
从10月25日起,“胡氏耀龙”化石标本将在中国古动物馆展出。
“胡氏耀龙”生活在侏罗纪时期,身体全长超过40厘米,属于鸟翼类,代表了和鸟类关系最为接近的恐龙之一。不同于其他已知恐龙,“胡氏耀龙”长有4枚长约20多厘米的带状尾羽。更有意思的是,它的其他羽毛均未形成为类似鸟类飞羽的构造,虽然“胡氏耀龙”的前肢长于后肢,形成了类似原始鸟类的前肢,但由于没有飞羽,“胡氏耀龙”并不具有飞行能力。
“胡氏耀龙”的头短而高,具有类似于恐龙中的窃蛋龙类头骨的外形。但与多数窃蛋龙不同的是,它的上、下颌均具牙齿且前倾。更有意思的是,这些牙齿的大小出现了分化,形成了类似于一些哺乳动物的犬齿或门齿的咬合结构。这在恐龙中是不常见的。
在骨骼形态上,“胡氏耀龙”的一个明显特征是尾椎极度退化,仅有16枚尾椎,远少于始祖鸟等。
这项研究由中国科学院古脊椎动物与古人类研究所的张福成、周忠和、徐星、汪筱林和CorwinSullivan共同完成。(生物谷Bioon.com)
生物谷推荐原始出处:
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.