It is interesting to compare the dentition and arms of these three dinosaurs. Allosaurus, or a T. rex-like dinosaur, had sharp pointy teeth. The Alvarezsaur, Haplocheirus, had many shorter teeth, and the most bird-like dinosaur of the group, Shuvuuia, had reduced peg-like dentition. Also note the three claws of roughly equal size of the Allosaurus, the thick short thumb and two skinny fingers of Haplocheirus, and the completely reduced single digit of Shuvuuia.
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Image Courtesy of Zina Deretsky, National Science Foundation
Dinosaur Discovery Helps Solve Piece of Evolutionary Puzzle
News story originally written on January 28, 2010
Scientists have discovered a new species of dinosaur called Haplocheirus sollers (which means simple, skillful hand). These dinosaurs lived during the Late Jurassic time period and are part of the family Alvarezsauridae. Scientists used to think that dinosaurs in this family were relatives of birds, but the fossils of the newly discovered dinosaurs show that they are not related to birds.
Dinosaurs in the Alvarezsauridae family are a bizarre group of bird-like dinosaurs with a large claw on the hand and very short, powerful arms.
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