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始祖鸟的发现被认为是19世纪最重要的科学发现之一,迄今为止共发现了7枚保存骨骼、羽毛印痕的化石标本和1枚单根羽毛化石标本。由于始祖鸟既显示了明显的爬行动物的特征又保存了精美的羽毛,140多年来人们一直将其作为介于恐龙与鸟类之间的“中间环节”(“missinglink”),但更倾向认为它是世界上最古老的鸟,或鸟类的始祖。由于始祖鸟化石稀少,加之地理分布十分局限,长期以来国际上一直围绕鸟类起源问题展开了激烈的争论,提出了各种各样的假说。直到20世纪90年代,在中国辽西晚中生代地层中发现了大量长羽毛的恐龙和原始鸟类化石,有力地支持了鸟类起源于小型兽脚类恐龙的学术观点,使赫胥黎140多年前提出的“假说”成为当今国际科学界占主流地位的学说和理论,基本解决了长期困扰国际科学界的鸟类起源问题。遗憾的是,在过去的几年中,中国一直没有发现与德国始祖鸟十分接近,或与德国始祖鸟处于同样进化水平的原始鸟类化石。这种缺憾使我们难以对鸟类定义问题进行深入的研究和探讨。2002年,笔者等在中国辽西早白垩世地层中发现了2种初鸟类化石,即中华神州鸟和东方吉祥鸟。通过比较解剖学研究和支序分析,这2种初鸟类要比始祖鸟略微进步一些,在研究鸟类的早期演化方面具有重要意义;但仍然难以对鸟类定义问题作进?
The discovery of the Archeopteryx was considered one of the most important scientific discoveries of the 19th century. To date, seven specimens of fossil remains of preserved bones and feathers and one single specimen of feathered fossils have been found. Since Archeopteryx has shown both obvious reptile features and beautiful feathers, it has been used for more than 140 years as a “missing link” between dinosaurs and birds, but it is more inclined to assume that it Is the oldest bird in the world or the ancestor of birds. Due to the rare archeopteryx fossils and the extremely limited geographical distribution, a great deal of controversy has been raised over the origin of birds for a long time in the world. Until the 1990s, a large number of long-feathered dinosaurs and primitive bird fossils were found in the Late Mesozoic strata in western Liaoning, effectively supporting the academic view that birds originated from small ornithopod dinosaurs, making Huxley more than 140 years ago The proposed “hypothesis” has become the dominant theory and theory in the international scientific community today, basically solving the problem of the origin of birds that have long plagued the international scientific community. Unfortunately, in the past few years, China has not found any primitive bird fossil that is very close to the German Archeopteryx or at the same level of evolution as the German Archeopteryx. This deficiency makes it hard for us to conduct an in-depth research and discussion on the definition of birds. In 2002, the author found two kinds of early bird fossils in the Early Cretaceous strata in western Liaoning, namely, China Shenzhou Bird and Oriental Lucky Bird. By comparing the anatomical study with the sequence analysis, these two species of early birds are slightly more advanced than those of Archeopteryx, and are of great importance in the study of the early evolution of birds. However, it is still difficult to make the definition of birds.