Suggestions that they were the direct descendants of theropod dinosaurs ( a group of bipedal meat - eaters that include allosaurus , velociraptor and tyrannosaurus ) caused quite a flap 有人说它是兽脚恐龙的后代（兽脚恐龙是一群食肉的两足恐龙，其中包括异龙、迅猛龙与暴龙） ，这引起了学界很大的注意。
2.
Dromaeosaruid theropods can be restricted in the unique family dromaeosauridae ; furthermore , this family may also be subdivided into two subfamilies dromaeosauridae and velociraptorinae 奔龙类自成一科，即奔龙科( dromaeosauridae ) ，它又可进一步分为奔龙亚科( dromaeosaurinae )与疾走龙亚科( velociraptorinae ) 。
3.
Together these advances have produced a highly detailed and revolutionary picture : feathers originated and diversified in carnivorous , bipedal theropod dinosaurs before the origin of birds or the origin of flight 综合这些证据，便能描绘出十分详尽的革命性图像：羽毛的起源与分化都发生于肉食性、两足步行的兽足类恐龙身上，比鸟类的起源、甚至飞行的起源都还要早。
4.
The cladogram proposed in the present paper also suggests that the maniraptoran troodontidae and ovkaptoridae should have the branched feathers , and that feathers evolve and initially diversify in terrestrial theropod dinosaurs before the origin of birds and their flight Opterm 、尾羽鸟类（窃蛋龙类）的cah却作沙、镰刀龙类的一加0 ? ?一奔龙类的s初00掀…一及mlerraptor等。此外，发现于蒙古的athere罚a 。
5.
Recently , a series of the feathered dinosaurs have been found from the jehol biota of western liaoning , northeast china , which give extremely strong evidences of the theropod hypothesis of bird origin and of the cursorial hypothesis of the avian flight origin . but the origin and early evolution of feathers have still been unanswered . in late 2000 , a well - preserved specimen of dromaeosaurids was excavated from the early cretaceous jiufotang formation of shangheshou , suburb of chaoyang city , western liaoning 2000年，辽西朝阳市上河首早白垩世九佛堂组地层中，发现了一件保存完好的长有羽毛的奔龙类化石，这是继北票四合屯、朝阳下三家子、凌源大王杖子之后长羽毛奔龙化石在辽西的又一次发现，为解决奔龙类的系统关系、羽毛的起源及早期演化提供了重要的实物资料。
6.
The feathers attached to the arms and the tail evidently possess the structures of " modern feathers " , which consisting of the central shafts ( rachis ) and parallel barbs . dromaeosaurids are unusual group of maniraptoran theropods . they share many similar or the same features with archaeopteryx or other primitive birds , such as : u - shaped furcula , uncinate process , laterally facing glenoid of shoulder girdle , comparatively long forelimb , large semilunate carple , retroverted pubis , ascending process of astragalus , and " modern feathers " with rachis and barbs etc . these facts indicate not only that dromaeosaurids had developed many bird - like characters in course of the advanced maniraptorans toward birds , but also that there seemed to be the co - evolutionary trend between the feathers and the skeletal bones 奔龙类是一类较为特殊的手盗龙类( maniraptora ) ，它具有许多与始祖鸟archaeopteryx甚至其它早期鸟类相似或接近的特征，主要表现在：叉骨u形与始祖鸟和孔子鸟类的相同，背肋钩状突在孔子鸟类和个别反鸟类中也存在，肩臼窝绝大部分指向侧方类似于始祖鸟，肩胛骨与乌喙骨间的夹角非常接近90也和始祖鸟的相似，前肢从比例上讲显得较长，大的半月形腕骨使肘部能向侧方折过来，耻骨伸向后下方，距骨上升突与原始鸟类中的为同源结构，羽毛已有显著的分化且具备了现代羽毛的基本结构等等。
