Year 2011 have yet belonged sauropodům , but even the birds have not done badly. Many new discoveries recorded mainly Enantiornithes group that combined archaic dinosaur characters with many evolutionary innovations, associated mainly with active flight (aileron, socket shoulder joint shifted on the side of the blade). We have already seen extensive revision of the group in terms of cranial anatomy (O'Connor & Chiappe 2011) and brought a lot of information and redescription rapaxavise, one of the best preserved while nejbazálnějších enantiornitů (O'Connor et al. 2011). The two articles I briefly wrote a blog .
Now comes another protipták: Qiliania Graffin was described in a study led by Ji Shu'Anem, an author who participated in virtually every major discoveries related to Chinese feathered dinosaurs (Ji & Ji 1996, Ji et al. 1998). A new discovery this time not from any of the "profláklých" formation, although the total is also much ignorance. Spodnokřídové Xiagou Formation, which is speech, is located in northwestern China (Changma Basin, Gansu Province) from the APTU (from 125-112 million years) and the known avifauna is dominated by remnants of basal ornituromorfa Gansus yumenensis . Among the 100 fossil skeletons, which have not yet been found - and which, though usually incomplete, often stored and impressions of soft tissues - has been identified and located the remains enantiornitů. Ji et al. (2011) now recognize these protiptačích remains of a new taxon, known only from two incomplete, partially articulated skeletons - one forms a complete left foot with part of the pelvic girdle, and the second consists of almost the entire right leg. Both specimens bear characters diagnostic for example Enantiornithes , abstract study, however, does not state what autapomorfie (unique derived characters) support erecting a new taxon. Ji et al. (2011), however, promise a unique three-dimensional preservation of fossils - the vast majority of the Lower Cretaceous bird fossils are broken and no apparent depth - providing new insight into protiptačí anatomy, evolution and diversity.
Qilianii if I was not paying a separate article, I had on hand only the abstract, other But information provided on his blog Andrew Cao . As usual, covered the phylogeny and, as usual, sophisticated Cauova Megamatrice threw a different result than by the original authors. Ji et al. (2011) is qilianii vykryli in close relationship to European Iberomesornis while Megamatrice found inside her as a sister taxon gobipterygidů bohaiornise. Explanation? According to Caua it is not surprising: if protiptáci achieve at least a fraction of the diversity of modern birds had to be between homoplazie (convergent derived characters) greatly expanded. Consider, after all, how surprising homoplazie morphological analysis revealed controversial Houde'a and Fain (2004), or even a great crested grebes (Podicipediformes) and the red (Gaviiformes), which is the nature of the similarities homoplastická fully accepted.
Qilianii if I was not paying a separate article, I had on hand only the abstract, other But information provided on his blog Andrew Cao . As usual, covered the phylogeny and, as usual, sophisticated Cauova Megamatrice threw a different result than by the original authors. Ji et al. (2011) is qilianii vykryli in close relationship to European Iberomesornis while Megamatrice found inside her as a sister taxon gobipterygidů bohaiornise. Explanation? According to Caua it is not surprising: if protiptáci achieve at least a fraction of the diversity of modern birds had to be between homoplazie (convergent derived characters) greatly expanded. Consider, after all, how surprising homoplazie morphological analysis revealed controversial Houde'a and Fain (2004), or even a great crested grebes (Podicipediformes) and the red (Gaviiformes), which is the nature of the similarities homoplastická fully accepted.
A. Cao with his Megamatricí time shot into the water enantiornitů: Qiliania is second from bottom. (Source: theropoda.blogspot.com)
Sources:
- http://theropoda.blogspot.com/2011/04/qiliania.html
- Fain MG, Houde P 2004 Parallel radiations in the primary clades of birds. Evolution 58(11): 2558–73
- Ji Q, Currie PJ, Norell MA, Ji S-A 1998 Two feathered dinosaurs from northeastern China. Nature 393(6687): 753–61
- Ji Q, Ji S-A 1996 [On the discovery of the earliest fossil bird in China ( Sinosauropteryx gen. nov.) and the origin of birds.] Chin Geol 10(233): 30–3 [in Chinese, transl. by Downs W]
- Ji S-A, Atterholt J, O'Connor JK, Lamanna MC, Harris JD, Li D-Q, You H-L, Dodson P 2011 A new, three-dimensionally preserved enantiornithine bird (Aves: Ornithothoraces) from Gansu Province, north-western China. ZOOL J Linn Soc 162 (1): 201-19
- O'Connor JC, Chiappe LM 2011 and revision of enantiornithine (Aves: Ornithothoraces) Skull Morphology. Palaeont J Syst 9 (1): 135-57
- O'Connor JC, Chiappe LM, Gao C, Zhao B, 2011 Anatomy of the Early Cretaceous bird Rapaxavis Ms (Aves: Enantiornithes). Acta Pol Palaeont doi: 10.4202/app.2010.0047
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