Featured Research

from universities, journals, and other organizations

Dino Tooth Sheds New Light On Ancient Riddle: Major Group Of Dinosaurs Had Unique Way Of Eating

Date:
June 30, 2009
Source:
University of Leicester
Summary:
Microscopic analysis of scratches on dinosaur teeth has helped scientists unravel an ancient riddle of what a major group of dinosaurs ate -- and exactly how they did it! Now for the first time, a study led by the University of Leicester, has found evidence that the duck-billed dinosaurs -- the Hadrosaurs -- in fact had a unique way of eating, unlike any living creature today.

These are teeth from the lower jaw of a hadrosaur, Edmontosaurus, showing its multiple rows of leaf-shaped teeth. The worn, chewing surface of the teeth is towards the top.
Credit: Vince Williams, University of Leicester

Microscopic analysis of scratches on dinosaur teeth has helped scientists unravel an ancient riddle of what a major group of dinosaurs ate -- and exactly how they did it!

Related Articles


Now for the first time, a study led by the University of Leicester, has found evidence that the duck-billed dinosaurs -- the Hadrosaurs -- in fact had a unique way of eating, unlike any living creature today.

Working with researchers from the Natural History Museum, the study uses a new approach to analyse the feeding mechanisms of dinosaurs and understand their place in the ecosystems of tens of millions of years ago. The results are published today in the Proceedings of the National Academy of Sciences.

Palaeontologist Mark Purnell of the University of Leicester Department of Geology, who led the research, said: "For millions of years, until their extinction at the end of the Cretaceous, duck-billed dinosaurs – or hadrosaurs - were the World's dominant herbivores. They must have been able to break down their food somehow, but without the complex jaw joint of mammals they would not have been able to chew in the same way, and it is difficult to work out how they ate. It is also unclear what they ate: they might have been grazers, cropping vegetation close to the ground - like today's cows and sheep - or browsers, eating leaves and twigs - more like deer or giraffes. Not knowing the answers to these questions makes it difficult to understand Late Cretaceous ecosystems and how they were affected during the major extinction event 65 million years ago.

"Our study uses a new approach based on analysis of the microscopic scratches that formed on hadrosaur's teeth as they fed, tens of millions of years ago. The scratches have been preserved intact since the animals died. They can tell us precisely how hadrosaur jaws moved, and the kind of food these huge herbivores ate, but nobody has tried to analyse them before."

The researchers say that the scratches reveal that the movements of hadrosaur teeth were complex and involved up and down, sideways and front to back motion. According to Paul Barrett palaeontologist at the Natural History Museum "this shows that hadrosaurs did chew, but in a completely different way to anything alive today. Rather than a flexible lower jaw joint, they had a hinge between the upper jaws and the rest of the skull. As they bit down on their food the upper jaws were forced outwards, flexing along this hinge so that the tooth surfaces slid sideways across each other, grinding and shredding food in the process".

The scratch patterns provide confirmation of a theory of hadrosaur chewing first proposed 25 years ago, and provides new insights into their ecology, say the researchers.

The research also sheds light on what the dinosaurs ate. Vince Williams of the University of Leicester said: "Although the first grasses had evolved by the Late Cretaceous they were not common and it is most unlikely that grasses formed a major component of hadrosaur diets. We can tell from the scratches that the hadrosaur's food either contained small particles of grit, normal for vegetation cropped close to the ground, or, like grass, contained microscopic granules of silica. We know that horsetails were a common plant at the time and have this characteristic; they may well have been an important food for hadrosaurs".

One of the big surprises of this study is that so much information about such large animals can be gleaned from such a tiny patch of tooth. "By looking at the pattern of scratches in an area that is only about as wide as a couple of human hairs we can work out how and what these huge herbivores were eating" notes Williams. "And because we can analyse single teeth, rather than whole skeletons, the technique has the potential to tell us a lot more about dinosaur feeding and the ecosystems in which they lived."

Notes:

1. The erroneous idea that all dinosaurs could chew is so widely accepted that the memorable 'Chewits' advertising campaigns of the 1980s were based on the idea. Note that the dinosaur shown in the adverts is not a hadrosaur:

http://www.youtube.com/watch?v=NJUwQIXPCBE

http://www.youtube.com/watch?v=420UecB2YZQ

2. The paper "Quantitative analysis of dental microwear in hadrosaurid dinosaurs, and the implications for hypotheses of jaw mechanics and feeding" by Vincent S. Williams, Paul M. Barrett and Mark A. Purnell is published in the Proceedings of the National Academy of Sciences (online Early Edition).

3. This study is based on Edmontosaurus: Lived USA and Canada 65-68 million years ago; Length up to 13 m, weight up to 3 tonnes; One of the most abundant dinosaurs of its time; Known from many complete skeletons, including several mummies with skin impressions and gut contents preserved.


Story Source:

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


Cite This Page:

University of Leicester. "Dino Tooth Sheds New Light On Ancient Riddle: Major Group Of Dinosaurs Had Unique Way Of Eating." ScienceDaily. ScienceDaily, 30 June 2009. <www.sciencedaily.com/releases/2009/06/090629200632.htm>.
University of Leicester. (2009, June 30). Dino Tooth Sheds New Light On Ancient Riddle: Major Group Of Dinosaurs Had Unique Way Of Eating. ScienceDaily. Retrieved December 21, 2014 from www.sciencedaily.com/releases/2009/06/090629200632.htm
University of Leicester. "Dino Tooth Sheds New Light On Ancient Riddle: Major Group Of Dinosaurs Had Unique Way Of Eating." ScienceDaily. www.sciencedaily.com/releases/2009/06/090629200632.htm (accessed December 21, 2014).

Share This


More From ScienceDaily



More Fossils & Ruins News

Sunday, December 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Researchers Bring Player Pianos Back to Life

Researchers Bring Player Pianos Back to Life

AP (Dec. 17, 2014) Stanford University wants to unlock the secrets of the player piano. Researchers are restoring and studying self-playing pianos and the music rolls that recorded major composers performing their own work. (Dec. 17) Video provided by AP
Powered by NewsLook.com
Domestication Might've Been Bad For Horses

Domestication Might've Been Bad For Horses

Newsy (Dec. 16, 2014) A group of scientists looked at the genetics behind the domestication of the horse and showed how human manipulation changed horses' DNA. Video provided by Newsy
Powered by NewsLook.com
Mozart, Beethoven, Shubert and Bizet Manuscripts to Go on Sale

Mozart, Beethoven, Shubert and Bizet Manuscripts to Go on Sale

AFP (Dec. 16, 2014) A collection of rare manuscripts by composers Mozart, Beethoven, Shubert and Bizet are due to go on sale at auction on December 17. Duration: 00:57 Video provided by AFP
Powered by NewsLook.com
Old Ship Records to Shed Light on Arctic Ice Loss

Old Ship Records to Shed Light on Arctic Ice Loss

Reuters - Innovations Video Online (Dec. 15, 2014) Researchers are looking to the past to gain a clearer picture of what the future holds for ice in the Arctic. A project to analyse and digitize ship logs dating back to the 1850's aims to lengthen the timeline of recorded ice data. Ben Gruber reports. Video provided by Reuters
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