Welcome to Visited Vertebrata Palasiatica, Today is

Vertebrata Palasiatica

   

A new feathered dinosaur from Early Cretaceous of northern China highlighting the complexity of early pennaraptoran evolution and comments on several relevant conceptual and methodological issues

XU Xing#br#   

  1. (Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044)

中国北方早白垩世一新的长羽毛恐龙彰显廓羽盗龙类早期演化复杂性及对若干相关概念和方法的评论

徐  星   

  1. (中国科学院古脊椎动物与古人类研究所  北京 100044)

PDF

Abstract:

 Recent discoveries of early-diverging pennaraptoran fossils have shed light on the origin of birds and, in particular, the evolution of defining avian features such as pennaceous feathers and flight capability. Here I report a new pennaraptoran dinosaur based on a fossil recovered from the Lower Cretaceous Jiufotang Formation of western Liaoning, China. Despite exhibiting a combination of derived features observed across distinct pennaraptoran lineages, this new taxon is likely an early-diverging deinonychosaurian. Most notably, it possesses exceptional plumage characteristics: it represents the first known early-diverging pennaraptoran to bear both large pedal feathers and highly elongated rectrices; these elongated rectrices are substantially more abundant than those of other early-diverging pennaraptorans, bearing a superficial resemblance to the tail plumes of peacocks; and its wing feathers form the proportionally largest feathered wings among non-avialan pennaraptorans—even with relatively short bony forelimbs—indicating a decoupling of forelimb skeletal length and feathered wing surface area. This discovery underscores the complexity of early pennaraptoran evolution and raises several conceptual and methodological issues in pennaraptoran research. These issues include how to recover a robust pennaraptoran phylogeny, how to infer the aerial behavior and habitat ecology of early-diverging pennaraptorans, and how to define feathers and birds. I briefly address these issues in this paper.

Key words: Jianchang, Liaoning, Early Cretaceous, Jiufotang Formation, Pennaraptora, feathers, phylogeny, morphology, habitat ecology and aerial behavior

摘要：

近期的早期分异廓羽盗龙类化石发现推进了鸟类起源研究，尤其揭示了像羽毛和飞行能力这样的鸟类定义性特征的演化。基于产自中国辽宁西部下白垩统九佛堂组的一件化石，我在本文报道一新的廓羽盗龙类。尽管这一新物种具有不同廓羽盗龙支系的衍征，它很可能属于早期分异的恐爪龙类。最重要的是，这一新物种展现了特别异常的羽毛特征：它代表首个同时具有大型足羽和极度加长尾羽的廓羽盗龙类；长尾羽数量明显多于其他早期分异的廓羽盗龙类，某种程度和孔雀尾羽表面相似；它的翼羽形成了非鸟廓羽盗龙类中相对最大的羽翼—尽管其骨质前肢较短—这指示前肢骨骼长度和羽翼面积不相关。这一发现彰显了廓羽盗龙类早期演化的复杂性，并引发了廓羽盗龙类研究当中的存在的几个概念性和方法性问题，包括如何重建一个稳健的廓羽盗龙类系统发育、如何推断早期廓羽盗龙类的飞行行为和栖息地生态以及如何定义羽毛和鸟类。

关键词: 辽宁建昌, 早白垩世, 九佛堂组, 廓羽盗龙类, 羽毛, 系统发育, 形态, 栖息地生态和飞行行为

Website Copyright © Vertebrata Palasiatica
Tel: (010)88369180　E-mail: bjs@ivpp.ac.cn
Powered by Beijing Magtech Co., Ltd.