近背突(英语:proximodorsal process)是主龙类动物骨骼的一个特征。它是骨盆上的一对突舌或刀片状的凸缘,并用作腿部肌肉附着的固定点。这个结构对中生代鸟类和手盗龙类恐龙的解剖学和比较形态学中特别重要。骨盆由三对骨骼和一个荐骨组成。这三对骨骼分别称为髂骨坐骨耻骨。在坐骨上可能有闭孔突和/或近背突。更原始的条件是没有近背突,而有大的闭孔突。在原始鸟类中,坐骨是复杂的,通常具有较小甚至不存在的闭孔突,而近背突向上延伸至髂骨的前部。这一结构在是始祖鸟孔子鸟反鸟类中的普遍存在[1] 。分布于南美的驰龙科半鸟亚科兼具两种结构[2] ,同时具有大的闭孔突和近背突[3]


参考资料 编辑

  1. ^ Witmer, Lawrence M. (2002) "The Debate on Avian Ancestry: Phylogeny, Function, and Fossils." pp. 3-30 in "Mesozoic Birds: above the heads of dinosaurs" Chiappe, L.M., and Witmer, L.M. (eds.) University of California Press, Berkeley.
  2. ^ Forster, Catherine, Sampson, Scott D., Chiappe, Luis M., Krause, David W. (1998) "The Theropod Ancestry of Birds:New Evidence from the Late Cretaceous of Madagascar" "Nature" 279:1915-1919. 20 march 1998
  3. ^ Makovicky, Peter J., Apestguia, Sebastian, Agnolin, Frederico L. (2005) "The earliest dromaeosaurid theropod from South America" "Nature" 437:1007-1011 13 October 2005.