But the more I find out about it, the more exciting it seems. The heart's four chambers and single aorta comprise the same sort of efficient blood pump that supports the active lifestyle and rapid metabolism of birds and mammals today. Although the reptile system demands less energy, it also delivers less oxygen to the body, leaving reptiles relatively slow and sluggish. Horner said that because of the Willo study by North Carolina scientists, he and other researchers will now start doing CT scans on any intact dinosaur fossils they find. Among the effects of the heart discovery, Horner said, is a boost for the idea that birds evolved from dinosaurs, a theory that is becoming more widely accepted by paleontologists.
Birds also have four-chambered hearts.
Thescelosaurus lived during the Late Cretaceous Period, the very end of the reign of dinosaurs. Typically only dinosaur bones turn to fossils that survive the ages, while the flesh and blood of the creatures decays soon after their death. While we've known about this kind of dinosaur for a long time, because of the extraordinary preservation of it and technology we now have available to us, we can now see things we've never seen before. The Billings Gazette, a division of Lee Enterprises .