過(guò)去二十年在中國(guó)有關(guān)長(zhǎng)羽毛獸腳類(lèi)恐龍的發(fā)現(xiàn),,使我們對(duì)鳥(niǎo)類(lèi)演化及飛行起源的認(rèn)識(shí)發(fā)生了巨大改變,,其中包括這樣一個(gè)觀(guān)點(diǎn)的提出:著名的始祖鳥(niǎo)化石與現(xiàn)代鳥(niǎo)類(lèi)的祖先也可能還有一些距離?,F(xiàn)在,,隨著另一只像鳥(niǎo)類(lèi)的恐龍?jiān)谥袊?guó)遼寧省“髫髻山組”(中-晚“侏羅紀(jì)”)的發(fā)現(xiàn),始祖鳥(niǎo)又回到了其應(yīng)有的位置,。新的系統(tǒng)發(fā)生分析恢復(fù)了始祖鳥(niǎo)作為一種早期分化的“鳥(niǎo)翼類(lèi)”的地位,,也重新將“傷齒龍”確定為“鳥(niǎo)翼類(lèi)”的姐妹類(lèi)群。
這些結(jié)果與中-晚“侏羅紀(jì)”鳥(niǎo)類(lèi)在亞洲的早期分化以及鳥(niǎo)類(lèi)靠拍打前肢來(lái)飛行的行為的單一起源觀(guān)點(diǎn)是一致的,。(生物谷Bioon.com)
生物谷推薦英文摘要:
Nature doi:10.1038/nature12168
A Jurassic avialan dinosaur from China resolves the early phylogenetic history of birds
Pascal Godefroit,Andrea Cau,Hu Dong-Yu, Francois Escuillié,Wu Wenhao & Gareth Dyke
The recent discovery of small paravian theropod dinosaurs with well-preserved feathers in the Middle–Late Jurassic Tiaojishan Formation of Liaoning Province (northeastern China) has challenged the pivotal position of Archaeopteryx, regarded from its discovery to be the most basal bird. Removing Archaeopteryx from the base of Avialae to nest within Deinonychosauria implies that typical bird flight, powered by the forelimbs only, either evolved at least twice, or was subsequently lost or modified in some deinonychosaurians. Here we describe the complete skeleton of a new paravian from the Tiaojishan Formation of Liaoning Province, China. Including this new taxon in a comprehensive phylogenetic analysis for basal Paraves does the following: (1) it recovers it as the basal-most avialan; (2) it confirms the avialan status of Archaeopteryx; (3) it places Troodontidae as the sister-group to Avialae; (4) it supports a single origin of powered flight within Paraves; and (5) it implies that the early diversification of Paraves and Avialae took place in the Middle–Late Jurassic period.