Beipiaosaurus

*Beipiaosaurus inexpectus*

***Beipiaosaurus*** is a genus of therizinosauroid theropod dinosaur from Early Cretaceous China. They were small for therizinosaurs, having been about 7ft (2 meters) long and perhaps as heavy as 201lbs (91kg). It was discovered in 1996 and named in 1999. Before the discovery of *Yutyrannus*, it was the largest non-avian dinosaur known from direct evidence to have been feathered. Analysis of melanosomes preserved in the specimen BMNHC PH000911 imply that the neck feathers of *Beipiaosaurus* were brown in color.

The exact classification of therizinosaurs had in the past been hotly debated, since their prosauropod-like teeth and body structure indicate that they were generally herbivorous, unlike typical theropods. *Beipiaosaurus*, being considered to be a primitive therizinosauroid, has features which suggest that all therizinosauroids, including the more derived Therizinosauridae, are coelurosaurian theropods, not sauropodomorph or ornithischian relatives as once believed.

## JPInstitute.com Description

Beipiaosaurus had the longest feathers of any dinosaur yet found. Classified as a plant-eater, it is thought that these dinosaurs would also have fed on insects a great deal of the time. It is considered a bird-like dinosaur and shared a number of features that are now found on modern birds.

Described in 1999, Beipiaosaurus is one of a few known bird-like dinosaurs. It came from the famous shale quarries of Liaoning, China, which are well known for producing many incredibly detailed fossils of small dinosaurs and birds. Most of the bird/dinosaur relationship studies are conducted on specimens from this quarry, as unique ecological conditions preserved even the soft parts of the animals that died at this site. These unusual conditions allowed for the perfect preservation of feathers.

Beipiaosaurus remains are fragmentary, but they do show that it was bipedal like other therizinosaurs and that it had sharp, curved hand claws and protofeathers.

## Dinosaur Field Guide Description

Beipiaosaurus ("Beipiao lizard"') is one of the therizinosaurs, a very strange group of theropods. Therizinosaurs (also known as "sloth dinosaurs") have very short, heavy feet, wide bellies, long necks, big claws, and small heads at the end of long necks. Their teeth are leaf shaped, like those of plant-eating dinosaurs, which makes them plant-eating members of the family of meat-eating dinosaurs! Beipiaosaurus is known from one partial skeleton from the Yixian Formation in northeastern China.The volcanic ash that formed the mud of this formation was so fine-grained that it preserved very small details of the animals buried in it. Fossils show that Beipiaosaurus's body was covered with long, slender filaments. These filaments were a sort of protofeather, a body cover that eventually evolved into true feathers in birds and some other dinosaurs (such as Caudipteryx). The protofeathers of Beipiaosaurus might have been used for insulation or for display, or for both.

### Fun Facts

Beipiaosaurus is the smallest known therizinosaur. Its giant relative Therizinosaurus was almost as big as T-rex and hau claws almost 5 feet (90 cin) long!

### Trivia

Beipigosaurus is the first therizinosaur known to have protofeathers.

## Links

http://web.archive.org/web/20031008032333fw\_/http://www.jpinstitute.com/dinopedia/dinocards/dc\_beipi.html
https://web.archive.org/web/20080723140602/http://kids.yahoo.com/dinosaurs/129--Beipiaosaurus

## References

1. ↑ https://www.academia.edu/6860358/Melanosome\_evolution\_indicates\_a\_key\_physiological\_shift\_within\_feathered\_dinosaurs