Anonymous asked in 社會與文化語言 · 1 decade ago


Sinornithosaurus^4,Microraptor^5 and NGMC 91 are preserved with patches of integumentary covering,although the full distribution of body covering on these taxa is unknown。In NGMC 91 integumentary filaments are distributed across the entire skull,body,limbs and tail,except for the distal hindlimbs(Fig.5)。Unlike Sinosauropteryx^6,the structure and distribution of filaments are heterogeneous。There are three basic types of filamentous structure: single fibres,long”sprays”of fibres that resemble the plumulaceous feathers of Protarchaeopteryx^2,and fibres oriented around a central axis in a herring-bone pattern that resembles the remiges of Caudipteryx。Across the entire skeleton the filamentous covering is heavy and matted because filaments are preserved between several layers of sediment。In most cases the integumentary structures lie at around 90度to the skeletal elements。

Recent models of feather evolution based on development^27 predict that feathers went through evolutionary stages of unbranched ules, followed by the development of a rachis and finally barbs。The shape of the filaments on NGMC 91 meet these predictions,as several of these patterns are present on the specimen。

On the skull,loosely organized,oriented unbranched fibres are exposed along the midline(Fig.4b)。This is not a plume or crest because several planes of matted filaments are separated by sediment。The entire head was apparently covered with a thick mat of filaments。These filaments extend a minimum of 2 cm from the skull。 On the back of the neck,the filaments are longer,extending 3.2 cm from the neck and curving posteriorly。

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  • Anonymous
    1 decade ago
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    Sinornithosaurus ^ 4,Microraptor ^ 雖然在這些taxa上包括的身體的豐滿的分發是未知的,但是5和NGMC 91被幾片integumentary 保護包括 。除了遠端的hindlimbs(圖5),在NGMC 91根integumentary 細絲被穿過整個頭顱,身體,肢和尾巴分發 。與Sinosauropteryx不同 ^ 6,細絲的架構和分發是不同的 。有3 類基本的絲的架構︰ 單個的纖維,長時間 」水霧 」象Protarchaeopteryx的plumulaceous 羽毛的纖維 ^ 2,以及在象Caudipteryx的remiges的一種鯡魚骨頭圖案裡的在主軸線周遭面向的纖維 。穿過整個骨骼絲的包括是沉重並且被鋪席子的,因為細絲被在幾層沈澱物之間保護 。多數情況下integumentary 架構存在於大約90 度對輪廓的要素 。基於發展的羽毛演化的新近的模型 ^ 27 預言羽毛經歷unbranched ules的進化的階段,隨後有rachis的發展和最後倒刺 。關於NGMC 91 集會的細絲的形式這些預言,一些這些圖案在樣品上存在 。在頭顱上,鬆弛組織,面向的unbranched 纖維被沿著midline(圖4 b)暴露 。這不是一支羽毛或者鳥冠,因為鋪席子的細絲的幾架飛機被沈澱物分開 。整個頭顯然為一個細絲的濃的墊席所覆蓋 。這些細絲延長至少離頭顱2厘米 。 在脖子後,細絲更長,延長離脖子3.2厘米並且弄彎posteriorly 。

    Source(s): 65dffuyg.
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