Reduced plumage and flight ability of a new Jurassic paravian theropod from China

New Specimens ofAnchiornis huxleyi(Theropoda: Paraves) from the Late Jurassic of Northeastern China

“…Later discoveries of closely related paravians further cloud the phylogenetic position of Anchiornis huxleyi as well as other paravians (Xu et al, 2011;Tuner et al, 2012;Agnolín and Novas, 2013;Godefroit et al, 2013aGodefroit et al, , 2013bFoth et al, 2014;Brusatte et al, 2014). Yet, despite its importance and being known from a large number of specimens, the morphology of this taxon has only been described briefly Hu et al, 2009;Li et al, 2010;Zheng et al, 2014).…”

“…In addition to many fossil mammals (Meng et al, 2006;Luo et al, 2007aLuo et al, , 2007bLuo et al, , 2011Zhou et al, 2013), pterosaurs (Ji and Yuan, 2002;Lü et al, 2009), salamandroids (Gao and Shubin, 2012) and insects (Ren et al, 2010), discoveries of feathered dinosaurs in Jianchang County have considerably improved our understanding of the evolution and paleobiology of the Paraves (Xu et al, , 2011Zheng et al, 2009;Longrich et al, 2012;Godefroit et al, 2013aGodefroit et al, , 2013b. Fossil deposits in the Tiaojishan Formation in Jianchang County have been dated to ~160 million years ago (Wang et al, 2013), thus, Late Jurassic (Oxfordian) in age (Cohen et al, 2013).…”

“…These deposits have furnished the most abundant collection of Jurassic paravians in the world. Fossils discovered in these deposits include multiple specimens of Anchiornis huxleyi, Xiaotingia zhengi, Aurornis xui, and Eosinopteryx brevipenna (Xu et al, , 2011Hu et al, 2009;Zheng et al, 2009;Godefroit et al, 2013aGodefroit et al, , 2013b.…”

Aerodynamic performance of the feathered dinosaur Microraptor and the evolution of feathered flight

“…Phylogenetic studies nest long-tailed birds (Archaeopteryx and relatives) within Paraves 6,7 ; as fossil members of several non-avialan lineages had well-developed, asymmetric feathers (equated with flight) 4,5 , it is certain that birds were not the only theropod lineage to possess some degree of aerial ability. Just how paravians utilized their feathered wings and what this may mean for the evolution of gliding and flapping remains much debated 1,11,12 .…”

“…140-66 Myo) fossils have closed the anatomical gap between non-avialan dinosaurs and birds (Avialae) 3 and have demonstrated that feathers (including asymmetric flight feathers) are not uniquely avialan adaptations 4,5 . Within the region of the dinosaur tree where birds diverged 6,7 , a diversity of paravian theropods is now known to have had well-developed feathers on their legs and tails, as well as on their arms (for example, Archaeopteryx, Microraptor, Anchiornis and Eosinopteryx) 4,5,7,8 .…”