威尼斯正规官网-威尼斯官方网站-首页

     威尼斯正规官网 >> 出版物 >> 古脊椎动物学报

学报文章下载

早期鸟类及其近亲的腹肋腔:大小和功能

发表日期:2015-04-20来源:放大 缩小

编辑:邹晶梅,郑晓廷,王孝理,张晓梅,周忠和

摘要:对中生代鸟类及与其亲缘关系密切的非鸟兽脚类腹肋腔的大小和形态进行了研究。据报道,在兽脚类中,腹肋腔的大小与个体大小正相关。然而与早期报道相反,基干鸟类的腹肋腔按个体大小比例似乎比非鸟兽脚类的大,这表明在缺乏前后向充分发育的胸骨时,腹肋可能作为一种补偿性结构,具有附着肌肉的功能。像鳄鱼一样,具有胸骨的早期鸟类的近端一排腹肋与胸骨相关联,表明这两种结构在功能上可能是一个整体;但在所有腹肋结构中都没有发现任何用来附着肌肉的痕迹,所以这一观点还没有此方面证据的支撑。或者,大型的腹肋腔可能与呼吸功能以及鸟类飞翔需要的大量氧气供应有关。由于这些细弱骨骼结构的保存往往不完整,好的样本太少,以至于无法从对腹肋资料的统计分析中得出重要的结论。
关键词:热河生物群,白垩纪,Paraves, 鸟纲,腹肋,胸骨,会鸟

卷期:第53卷,第2期

 

The gastral basket in basal birds and their close relatives: size and possible function
Jingmai K. O’CONNOR,ZHENG Xiao-Ting,WANG Xiao-Li,  ZHANG Xiao-Mei, ZHOU Zhong-He

Abstract  Here we investigate the size and morphology of the gastral basket in non-neornithine Mesozoic birds and their close non-avian dinosaur relatives. The size of the gastral basket reportedly increases with body size in the Theropoda. However, contra earlier reports basal birds appear to have proportionately large gastral baskets compared to non-avian theropods, suggesting gastralia may have functioned as a compensatory feature for muscle attachment in the absence of a craniocaudally extensive sternum. As in crocodilians, the proximal row of gastralia in basal birds articulates with the sternum when present suggesting the two features may have functioned as a unit; this hypothesis is not supported by any scars to indicate the gastralia served as points of muscle attachment. Alternatively, the large size of the gastral basket may be related to its respiratory function and the high oxygen demands of powered flight in birds. Due to incomplete preservation of these delicate elements as a unit, sample size is too low to draw significant results from statistical analysis of this element.
Keywords  Jehol Biota, Cretaceous, Paraves, Aves, gastralia, sternum, Sapeornis

附件:

威尼斯正规官网|威尼斯官方网站

XML 地图 | Sitemap 地图