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Thescelosaurus was a small dinosaur living near the end of the Age of Dinosaurs. Its run-of-the-mill appearance assured it a position of relative obscurity until a specimen nicknamed "Willo" brought the genus to prominence. Preserved in the stone within Willo's chest cavity is a feature some scientists have interpreted as the imprint of a four-chambered heart. Since birds and mammals also have four-chambered hearts this discovery, if confirmed, would support the view of dinosaurs as active, warm-blooded creatures.

In hindsight, the decades-old name of this animal may be appropriate: Thescelosaurus, (Greek theskelos="marvelous", sauros="lizard") the Marvelous Lizard!

Vital Statistics

Genus Name: Thescelosaurus ("wonderful lizard")
Type Species: * T. neglectus (Gilmore, 1913)
Length: 13 feet (4 meters)
Weight: 1/3 ton
Time: 72-66 million years ago (Late Cretaceous)
Place: Colorado, Montana, S. Dakota, Wyoming,
  Alberta, Saskatchewan
Diet: plant-eater (herbivore)

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