The origin of birds from theropod dinosaurs,by any measures,is the most eye-catching evolutionary transition in the history of life,which encompasses numerous extensive morphological and biological *** to postcranium,...
详细信息
The origin of birds from theropod dinosaurs,by any measures,is the most eye-catching evolutionary transition in the history of life,which encompasses numerous extensive morphological and biological *** to postcranium,little progress has been made regarding the evolutionary assemblage of the birds’skull,because of few detailed early records of cranial materials of stem *** is the oldest known record of the Paraves(~160 Ma),the most inclusive clade that contains all living birds but not Caudipteryx or *** hundreds of known specimens,Anchiornis constitutes an ideal taxon for investigating morphological modifications across the theropod-bird transition,but its cranial morphology remains *** we present in-depth description of the cranial morphology of Anchiornis based on three-dimensional reconstruction of a well-preserved specimen,including elements from the temporal and palatal regions that are poorly recognized *** study shows that Anchiornis retains the plesiomorphic dinosaurian condition in having a diapsid akinetic *** mixture of cranial characters,shared with dromaeosaurids,troodontids,and stemward avialans,present in Anchiornis demonstrates the complex history of early avialan cranial evolution.
鸟类的起源问题历经一百多年的科学研究,近年来在学术界已有较大共识,即鸟类来自属于小型兽脚类恐龙的一支,始祖鸟依然是目前学界比较公认的已知最早、最为原始的鸟类(Xu et al.,2014).历经1.5亿年演化历史的鸟类家族,目前在地球上还生...
详细信息
鸟类的起源问题历经一百多年的科学研究,近年来在学术界已有较大共识,即鸟类来自属于小型兽脚类恐龙的一支,始祖鸟依然是目前学界比较公认的已知最早、最为原始的鸟类(Xu et al.,2014).历经1.5亿年演化历史的鸟类家族,目前在地球上还生活了超过10000个种类,几乎遍布全球各个角落.然而鸟类演化大戏的上半场(1.5~0.66亿年),虽然最为扑簌迷离,然而来自中国早白垩世,特别是热河生物群发现的许多鸟类化石成为了其中的主角.
暂无评论