Occurrence

Belonging to what has been collectively called the Jehol Biota, the feathered dinosaurs have been found in several different formations (Wang & Zhou 2003, Zhou et al. 2003). These formations outcrop in a series of basins roughly defined by the cities of Kailu in the north, Lingyuan in the west, Shenyang in the east, and the coastline in the south (Figure 1, see color insert). The superpositional relationships and dating of these units is in a nascent stage, yet two formations are classically...

What Are Dinosaurs

Theropods Timeline

Any discussion of feathered dinosaurs requires some definition of what dinosaurs are and how they relate to one another. Dinosaurs are a monophyletic group of archosaurs Bakker amp Galton 1974, Gauthier 1986, Novas 1996 . In a general phylogenetic sense, they are composed of two great groups, the ornithischians and the saurischians Figure 3 Sereno 1996 . Ornithischians include specialized herbivorous forms like stegosaurs, hadrosaurs the duck-bills , and ceratopsians e.g., Triceratops ....

Psittacosaurs And Pterosaursmuch Earlier Origins Of Integumentary Structures

It is interesting to note that some other dinosaurs and near dinosaur relatives have also been found with filamentous epidermal coverings. The best known of these is the pterosaur Sordes pilosos Sharov 1971 . Pterosaurs are flying reptiles that are extremely closely related to dinosaurs. However, the interpretation of an epidermal covering on these specimens has remained controversial, and some authors have suggested that the integument is actually internal structures called actinofibrels,...

The Origin Of Feathers

Sihetun Liaoning Province

I remember well when the thought of the eye made me cold all over, but I have got over this stage of the complaint, and now small trifling particulars of structure often make me very uncomfortable. The sight of a feather in a Peacock s tail, whenever I gaze at it, makes me sick. So said Charles Darwin 1887 referring to his contemplation of the evolution of feathers. Because feathers are such complex structures, are unique to a single and diverse group, and fulfill so many functions in avian...