Theropoda

Theropoda is a clade of sauriscian dinosaurs, characterized by limbs with three clawed toes and hollow bones.This group existed from the Carnian age of the Late Triassic Period (231.4 Ma) to the end of the Cretaceous (66 Ma), and included all the large land carnivorous dinosaurs. Their name comes from ancient Greek, joining words with the meaning of 'wild beast' and 'foot'. Most of them were carnivorous dinosaurs, just like their basal ancestry, but some Theropoda groups evolved to the direction of herbivorous, omnivorous, insectivorous or piscivorous feeding. Birds have evolved from this group in the Jurassic period. Theropods was a diverse group regarding to their skin texture covering - some group had scales, others possessed feathers or feather-like filaments. They also showed a great variety in sizes; the smallest was the Anchiornis huxleyi with 110 grams in weight and 34 centimeters in length, and the largest theropods were such huge terrestrial carnivores like Tyrannosaurus, Spinosaurus, or Giganotosaurus.[1][2][3][4]

Scientific references

[1] Rauhut, O.W. (2003): The Interrelationships and Evolution of Basal Theropod Dinosaurs. Blackwell Publishing, 213 pp. ISBN 0-901702-79-X

[2] Holtz, T.R.; Jr; Brinkman, D.L.; Chandler, C.L. (1998): Dental morphometrics and a possibly omnivorous feeding habit for the theropod dinosaur Troodon. GAIA, 15: 159-166.

[3] Martínez, Ricardo N.; Sereno, Paul C.; Alcober, Oscar A.; Colombi, Carina E.; Renne, Paul R.; Montanez, Isabel P.; Currie, Brian S. (2011): A basal dinosaur from the dawn of the dinosaur era in Southwestern Pangaea. Science, 331 (6014): 206-210. doi: 10.1126/science.1198467.

[4] Xu, X.; Zhao, Q.; Norell, M.; Sullivan, C.; Hone, D.; Erickson, G.; Wang, X.; Han, F. & Guo, Y. (February 2009): A new feathered maniraptoran dinosaur fossil that fills a morphological gap in avian origin. Chinese Science Bulletin, 54 (3): 430-435. doi: 10.1007/s11434-009-0009-6.