Avian Ancestors: A Review of the Phylogenetic Relationships of the Theropods Unenlagiidae, Microraptoria, Anchiornis and Scansoriopterygidae

@article{Agnolin2013AvianAA,
  title={Avian Ancestors: A Review of the Phylogenetic Relationships of the Theropods Unenlagiidae, Microraptoria, Anchiornis and Scansoriopterygidae},
  author={Federico L. Agnolin and Fernando E Novas},
  journal={Avian Ancestors},
  year={2013}
}
The phylogenetic affinities and morphological peculiarities of the bird-like dinosaur Borogovia gracilicrus from the Upper Cretaceous of Mongolia
TLDR
The lack of a falciform ungual, and the distinctive morphology of the second toe in B. gracilicrus are interpreted as a derived specialization among Troodontidae and not as retention of the plesiomorphic condition of non-paravian theropods.
Differential locomotor and predatory strategies of Gondwanan and derived Laurasian dromaeosaurids (Dinosauria, Theropoda, Paraves): Inferences from morphometric and comparative anatomical studies
TLDR
The distinctive morphological evolutionary pathways of these two dromaeosaurid clades seem to have been influenced by the particular locomotor and predatory specializations that characterized each of these lineages.
Osteology of Unenlagia comahuensis (Theropoda, Paraves, Unenlagiidae) from the Late Cretaceous of Patagonia
TLDR
Detailed analysis of Unenlagia anatomy resulted in the recognition of one possible additional Unenlagiidae synapomorphy (i.e., the presence of cup‐like iliac articulation on ischium), lending support to the interpretation that unen lagiids are stem‐Avialae.
New troodontid theropod specimen from Inner Mongolia, China clarifies phylogenetic relationships of later‐diverging small‐bodied troodontids and paravian body size evolution
A new troodontid (LH PV39) recovered from the Upper Cretaceous Wulansuhai Formation, Inner Mongolia, China, is described, highlighting the dorsoventrally compressed sacral centra. The completely
Comments on the Morphology of Basal Paravian Shoulder Girdle: New Data Based on Unenlagiid Theropods and Paleognath Birds
TLDR
The present paper aims to review some important topics on pectoral girdle anatomy related to flight origins and test whether Ostrom’s ideas still remain valid under this new context, based on available phylogenetic and anatomical frameworks.
Feather Evolution in Pennaraptora
TLDR
The origin and early evolution of complex feathers and flight abilities in paravian theropods were not linear processes, but more complex than previously thought.
Assesment and interpretation of negative forelimb allometry in the evolution of non-avian Theropoda
TLDR
It is proposed that proportionally longer arms of juveniles became adult traits in the small-sized and paedomorphic Aves, which suggests negative allometry of the forelimb in the ontogeny of most non-avian theropods.
A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight
TLDR
All parsimonious results support the hypothesis that each early paravian clade was plesiomorphically flightless, raising the possibility that avian flight originated as late as the Late Jurassic or Early Cretaceous.
Paravian Phylogeny and the Dinosaur-Bird Transition: An Overview
TLDR
It is concluded that troodontid affinities of anchiornithines, and dromaeosaurids affinITIES of microraptorians and unenlagiids are dismissed in favor of sister group relationships with Avialae, and main phylogenetic hypotheses that compete some topics about the non-avian dinosaur-bird transition are analyzed.
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