Featured Research

from universities, journals, and other organizations

Tooth is 'smoking gun' evidence that Tyrannosaurus rex was hunter, killer

Date:
July 16, 2013
Source:
University of Kansas
Summary:
Tyrannosaurus rex has long been popular with kids and moviemakers as the most notorious, vicious killing machine to roam the planet during the age of the dinosaurs. So, it may come as a shock that for more than a century some paleontologists have argued that T. rex was a scavenger, not a true predator -- more like a vulture than a lion. Indeed, a lack of definitive fossil proof of predation in the famous theropod has stirred controversy among scientists -- until now. Researchers have unearthed "smoking gun" physical proof that T. rex was indeed a predator, hunter and killer.

Researchers recently discovered the crown of a T. rex tooth lodged in the fossilized spine of a plant-eating hadrosaur that seems to have survived the attack.
Credit: Illustration by University of Kansas alumnus Robert DePalma II of The Palm Beach Museum of Natural History

Tyrannosaurus rex has long been popular with kids and moviemakers as the most notorious, vicious killing machine to roam the planet during the age of the dinosaurs.

Related Articles


So, it may come as a shock that for more than a century some paleontologists have argued that T. rex was a scavenger, not a true predator -- more like a vulture than a lion. Indeed, a lack of definitive fossil proof of predation in the famous theropod has stirred controversy among scientists -- until now.

"T. rex is the monster of our dreams," said David Burnham, preparator of vertebrate paleontology at the Biodiversity Institute at the University of Kansas. "But ever since it was discovered in Montana and named in the early 1900s, there's been a debate about whether these large carnivores were scavengers or predators. Most people assume they were predators, but the scientific evidence for predation has been really elusive. Yes, we've found lots of dinosaur skeletons with tooth marks that had been chewed up by something. But what did that really prove? Yes, these large carnivores fed on other dinosaurs -- but did they eat them while they were alive or dead? That's where the debate came in. Where was the evidence for hunt and kill?"

Now, Burnham is part of a team that has unearthed "smoking gun" physical proof that T. rex was indeed a predator, hunter and killer. In the Hell Creek Formation of South Dakota, Burnham and colleagues discovered the crown of a T. rex tooth lodged in the fossilized spine of a plant-eating hadrosaur that seems to have survived the attack. The team describes the find in the current issue of the Proceedings of the National Academy of Sciences.

Burnham's KU co-authors are Bruce Rothschild and the late Larry Martin, along with former KU student Robert DePalma II of The Palm Beach Museum of Natural History and Peter Larson of the Black Hills Institute of Geological Research.

"Robert DePalma was a student here at KU doing his master's thesis in the Hell Creek formation," said Burnham. "He found a specimen that represents the tail of one of these hadrosaurs. It had a distorted-looking bone growth. He came to me and said, 'What do you think is causing this?' So we cleaned it and could see a tooth embedded in one of these duck-billed dinosaur vertebrae. Then we went to Lawrence Memorial Hospital and used a CT machine to scan the bones -- and we saw all of the tooth."

Previous evidence for predation included T. rex fossil discoveries with preserved stomach contents that included the bones of a young ceratopsian (e.g., Triceratops or one of its kin). However, there was no evidence to conclude whether the ceratopsian was alive or dead when the T. rex made a snack of it.

By contrast, Burnham said the tooth was definitive evidence of hunting, after carefully measuring its length and the size of its serrations to ensure that it came from the mouth of a T. rex.

"Lo and behold, the tooth plotted out just exactly with T. rex -- the only known large theropod from the Hell Creek formation," he said. "We knew we had a T. rex tooth in the tail of a hadrosaur. Better yet, we knew the hadrosaur got away because the bone had begun to heal. Quite possibly it was being pursued by the T. rex when it was bitten. It was going in the right direction -- away. The hadrosaur escaped by some stroke of luck. The better luck is finding this fossil with the preserved evidence."

Because T. rex regularly shed its teeth, the predator went away hungry, but otherwise no worse for the encounter. It would have grown a new tooth to replace the one left behind in the hadrosaur's tail. This could have been a typical example of T. rex's hunting efforts, even if it didn't result in a meal.

"To make an analogy to modern animals, when lions go attack a herd of herbivores, they go after the sick and the slow," Burnham said. "Most of the time, hadrosaurs traveled in packs. This hadrosaur may have been a little slower, or this T. rex may have been a little faster -- at least fast enough to almost catch a duck-billed dinosaur."

This concrete proof of T. rex's predation continues a long relationship between KU paleontologists and the theropod, which lived in North America during the Late Cretaceous, some 65 million years ago. KU graduate Barnum Brown discovered the first documented remains of the dinosaur in Wyoming in 1900.


Story Source:

The above story is based on materials provided by University of Kansas. Note: Materials may be edited for content and length.


Journal Reference:

  1. R. A. DePalma, D. A. Burnham, L. D. Martin, B. M. Rothschild, P. L. Larson. Physical evidence of predatory behavior in Tyrannosaurus rex. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1216534110

Cite This Page:

University of Kansas. "Tooth is 'smoking gun' evidence that Tyrannosaurus rex was hunter, killer." ScienceDaily. ScienceDaily, 16 July 2013. <www.sciencedaily.com/releases/2013/07/130716135841.htm>.
University of Kansas. (2013, July 16). Tooth is 'smoking gun' evidence that Tyrannosaurus rex was hunter, killer. ScienceDaily. Retrieved March 5, 2015 from www.sciencedaily.com/releases/2013/07/130716135841.htm
University of Kansas. "Tooth is 'smoking gun' evidence that Tyrannosaurus rex was hunter, killer." ScienceDaily. www.sciencedaily.com/releases/2013/07/130716135841.htm (accessed March 5, 2015).

Share This


More From ScienceDaily



More Fossils & Ruins News

Thursday, March 5, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Long-Lost Ship Found? Microsoft Co-Founder Uncovers Wreckage

Long-Lost Ship Found? Microsoft Co-Founder Uncovers Wreckage

Newsy (Mar. 4, 2015) Microsoft co-founder Paul Allen says he has discovered the wreckage of the battleship Musashi in the central Philippines. Video provided by Newsy
Powered by NewsLook.com
Ancient Mummified Monk Found Inside Golden Buddha

Ancient Mummified Monk Found Inside Golden Buddha

Reuters - News Video Online (Mar. 4, 2015) A gold statue of Buddha housed at Hungary&apos;s Natural History Museum has been discovered to contain the mummified body of an ancient Chinese monk. Gavino Garay reports. Video provided by Reuters
Powered by NewsLook.com
Who Was The Wealthy Woman Buried Near King Richard III?

Who Was The Wealthy Woman Buried Near King Richard III?

Newsy (Mar. 3, 2015) A woman thought to have been an important person in Grey Friars monastery was found in a coffin near King Richard III. Her identity is unknown. Video provided by Newsy
Powered by NewsLook.com
Mass Grave Found Under Paris SuperMarket

Mass Grave Found Under Paris SuperMarket

Buzz60 (Mar. 3, 2015) Dozens of bodies were found under the Monoprix Supermarket in Paris. The company called in researchers to inspect the ground underneath where a hospital once existed from the 12th century to the 17th. Patrick Jones (@Patrick_E_Jones) has the details. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins