Advertisement.

EnchantedLearning.com is a user-supported site.
As a bonus, site members have access to a banner-ad-free version of the site, with print-friendly pages.
Click here to learn more.

ad
(Already a member? Click here.)



T. rex skull ZoomDinosaurs.com
Dinosaur
News
A Fossilized, Four-Chambered Dinosaur Heart Found in South Dakota, USA - May Indicate Warm-Bloodedness
April 20, 2000

Thescelosaurus A Thescelosaurus' fossilized four-chambered heart was recently found near Buffalo, South Dakota, USA. A CT scan (computed tomography) revealed a powerful, advanced heart that seems to indicate that Thescelosaurus was an active, warm-blooded animal. This dinosaur was dubbed "Willo" after the wife of the owner of the ranch where the dinosaur was found.

This 66 million year old heart has recently been analyzed -- it has four chambers and a single aorta, which is quite different from existing reptiles, but is similar to modern warm-blooded animals (like birds and mammals).

If true, this discovery suggests not only that Thescelosaurus may have been warm-blooded, but that many other dinosaurs may have been warm-blooded as well. This is because we now have evidence of warm-bloodedness in both Ornithischia and Saurischia (the two major groups of dinosaurs, which diverged early in the Mesozoic Era). Thescelosaurus was an ornithischian; birds, which are known to be warm-blooded, are saurischians.

Finding fossilized soft tissue (like a heart) is extremely unusual. Soft tisssue usually decays long before it can fossilize (fossilization is a process in which rock-like minerals replace organic tissue, forming a rocky copy of the original material).

Thescelosaurus


The name Thescelosaurus means "Marvelous Lizard"; this dinosaur was named by the paleontologist Charles W. Gilmore in 1913. The type species is T. neglectus.

Anatomy: Thescelosaurus had a small head, a bulky body, a long, pointed tail, and short arms. It was a hypsilophodontid and an ornithischian dinosaur about 10 to 13 feet (3-4 m) long and 3 feet (0.9 m) tall at the hips; it weighed roughly 665 pounds (300 kg). This ornithopod (a Hypsilophodontid) had a small skull, cheek pouches, cheek teeth, and a beak made of horn.

Fossils: One complete specimen and 8 incomplete Thescelosaurus skeletons, including skin impressions, have been found in Wyoming, Montana, and South Dakota in the USA and in Alberta and Saskatchewan, Canada.

RELATED LINKS
Rebuttal to the find from 2001: Tim Rowe, Earl McBride and Paul Sereno think that the "heart" is an ironstone concretion.

Printout on Thescelosaurus

North Carolina Museum of Natural Sciences, Raleigh, NC - where you can see Willo, the Thescalosaurus whose fossilized, four-chambered heart was found.

DinoHeart.org, a site on Willo

Information on dinosaur metabolism

A Geologic Time Chart.




Enchanted Learning®
Over 35,000 Web Pages
Sample Pages for Prospective Subscribers, or click below

Overview of Site
What's New
Enchanted Learning Home
Monthly Activity Calendar
Books to Print
Site Index

K-3
Crafts
K-3 Themes
Little Explorers
Picture dictionary
PreK/K Activities
Rebus Rhymes
Stories
Writing
Cloze Activities
Essay Topics
Newspaper
Writing Activities
Parts of Speech

Fiction
The Test of Time
iPhone app
TapQuiz Maps - free iPhone Geography Game

Biology
Animal Printouts
Biology Label Printouts
Biomes
Birds
Butterflies
Dinosaurs
Food Chain
Human Anatomy
Mammals
Plants
Rainforests
Sharks
Whales
Physical Sciences: K-12
Astronomy
The Earth
Geology
Hurricanes
Landforms
Oceans
Tsunami
Volcano
Languages
Dutch
French
German
Italian
Japanese (Romaji)
Portuguese
Spanish
Swedish
Geography/History
Explorers
Flags
Geography
Inventors
US History

Other Topics
Art and Artists
Calendars
College Finder
Crafts
Graphic Organizers
Label Me! Printouts
Math
Music
Word Wheels

Click to read our Privacy Policy

E-mail


Enchanted Learning Search

Search the Enchanted Learning website for:



Advertisement.



Advertisement.



Advertisement.



Copyright ©2000 EnchantedLearning.com ------ How to cite a web page