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Baminornis is the oldest known bird with a fused pygostyle, a skeletal feature that implies tail feathers. Its discovery pushed back current understanding of bird evolution and global distribution by 20 million years. Baminornis was about 15 cm in length, had many features in common with modern birds, including the capability for powered flight.

Life reconstruction of Heyuannia yanshini, depicting a male with a tail-feather fan

Life reconstruction of Heyuannia yanshini, depicting a male with a tail-feather fan displaying for an onlooking female.

Fujianvenator is an anchiornithid avialan from the Late Jurassic of China, whose discovery gave important insight to the evolution of birds. It had proportionately long legs, with the tibia twice the length of the femur. This suggests it may have been a strong runner, and possibly had a terrestrial or wading lifestyle. Fujianvenator was a small dinosaur, weighing about 640 g. As an avialan, it was almost certainly covered in feathers, though it does not seem likely to have been capable of flight.

The "dromaeo-avemorphs", as they are informally known (Paul, 2002), represent a group of early paravian theropods with asymmetrical feathers and an Archaeopteryx-like body. According to Hartman et al. (2019), the animals shown in this image might, together, form a clade (monophyletic group) without modern birds.

Diuqin is an unenlagiine dinosaur from the Late Cretaceous of what is now Argentina. Unenlagiines, known exclusively from South America, are usually classified as dromaeosaurs though this is sometimes debated. Like dromaeosaurs, they were covered in feathers, carnivorous, and had the large sickle-like claw on the inner toe of each foot. Unique to unenlagiines is their elongated snout, suggesting a piscivorous diet. Diuqin was a medium-sized unenlagiine, at about 4 m in length.

Simplified cladogram of Dinosauria with the distribution of feathers according to the fossil record. Despite its more ancient origin, it was only in maniraptoriformes that modern-type feathers (pennaceous feathers) have arisen (Based in Xu & Guo, 2009; Clarke, 2013; Godefroit et al., 2013; Han et al., 2014; Koshchowitz et al., 2014).

Caihong juji holotype specimen (PMoL-B00175). Photographs of the slab (a) and counter slab (b) and line drawing (c) of the specimen based on both slabs. Photograph (d) and line drawing (e) of a composite of the rostrum of the skull and mandible exposed on the counter slab and the post-rostrum cranium exposed on the slab. Arrows indicate lacrimal crests. Question mark indicates uncertain identification. Scale bars: 10 cm a–c, 1 cm d and e. aof antorbital fenestra, cav caudal vertebra, cev cervical vertebra, dr dorsal rib, dv dorsal vertebra, ect ectopterygoid, emf external mandibular fenestra, en external naris, f feather, fu furcula, ga gastralia, hy hyoid, il ilium, is ischium, la left angular, lar left articular, lc left coracoid, lcr lacrimal crest, ld left dentary, lf left, frontal, lfe left femur, lh left humerus, lj left jugal, ll left lacrimal, lma left maxilla, lm left manus, ln left nasal, lp left pes, lpa left palatine, lpo left postorbital, lq left quadrate, lqj left quadratojugal, lr left radius, ls left scapula, lsp left splenial, lsa left surangular, lsq left squamosal, lt left tibiotarsus, lu left ulna, ma mandible, mf maxillary fenestra, o orbit, p parietal, pm premaxilla, pt pterygoid, pu pubis, rar right articular, rc right coracoid, rd right dentary, rfe right femur, rh right humerus, rm right manus, rp right pes, rpra right prearticular, rq right quadrate, rr right radius, rs right scapula, rt right tibiotarsus, ru right ulna, scl sclerotic bones, sk skull, sy synsacrum

Restoration of Lucianovenator bonoi based on images of known remains and related genera. Proto-feathers for insulation in coelophysids and other early theropods have been supported by this study:[1]

Life restoration of Pampadromaeus barberenai based on known skeletal remains. Colours speculative, feathers based on presumed presence within all Ornithodira.

Anzu is a fairly large caenagnathid oviraptorosaurian dinosaur that grew to nearly 4 m in length, and weighed 200-300 kg. It was a bipedal dinosaur and was covered in feathers, with a large sloping crest atop its head. Typical of oviraptorosaurs, Anzu had a short toothless beak, an adaptation that suggests it was most likely herbivorous or possibly omnivorous.

Euryapteryx gravis restored based on skeletons and preserved moa feathers.

The holotype of Microraptor gui, IVPP V 13352 under normal light. This shows the preserved feathers (white arrow) and the 'halo' around the specimen where they appear to be absent (black arrows). Scale bar at 5 cm.

The holotype of Microraptor gui, IVPP V 13352 under normal light. This shows the preserved feathers (white arrow) and the 'halo' around the specimen where they appear to be absent (black arrows). Scale bar at 5 cm.