Navigation Links
Dinosaur-chewing mammals leave behind oldest known tooth marks
Date:6/16/2010

New Haven, Conn.Paleontologists have discovered the oldest mammalian tooth marks yet on the bones of ancient animals, including several large dinosaurs. They report their findings in a paper published online June 16 in the journal Paleontology.

Nicholas Longrich of Yale University and Michael J. Ryan of the Cleveland Museum of Natural History came across several of the bones while studying the collections of the University of Alberta Laboratory for Vertebrate Palaeontology and the Royal Tyrrell Museum of Palaeontology. They also found additional bones displaying tooth marks during fieldwork in Alberta, Canada. The bones are all from the Late Cretaceous epoch and date back about 75 million years.

The pair discovered tooth marks on a femur bone from a Champsosaurus, an aquatic reptile that grew up to five feet long; the rib of a dinosaur, most likely a hadrosaurid or ceratopsid; the femur of another large dinosaur that was likely an ornithischian; and a lower jaw bone from a small marsupial.

The researchers believe the marks were made by mammals because they were created by opposing pairs of teetha trait seen only in mammals from that time. They think they were most likely made by multituberculates, an extinct order of archaic mammals that resemble rodents and had paired upper and lower incisors. Several of the bones display multiple, overlapping bites made along the curve of the bone, revealing a pattern similar to the way people eat corn on the cob.

The animals that made the marks were about the size of a squirrel and were most likely gnawing on the bare bones for minerals rather than for meat, said Longrich. "The bones were kind of a nutritional supplement for these animals."

There are likely many other instances of mammalian tooth marks on other bones that have yet to be identified, including older examples, said Longrich. "The marks stood out for me because I remember seeing the gnaw marks on the antlers of a deer my father brought home when I was young," he said. "So when I saw it in the fossils, it was something I paid attention to."

But he points out that the Late Cretaceous creatures that chewed on these bones were not nearly as adept at gnawing as today's rodents, which developed that ability long after dinosaurs went extinct.


'/>"/>

Contact: Suzanne Taylor Muzzin
suzanne.taylormuzzin@yale.edu
203-432-8555
Yale University
Source:Eurekalert  

Related biology news :

1. Carnivorous mammals track fruit abundance
2. Small mammals -- and rest of food chain -- at greater risk from global warming than thought
3. Large mammals need protected areas, forest cover in India
4. Tree-dwelling mammals climb to the heights of longevity
5. Researchers use new acoustic tools to study marine mammals and fish
6. Study shows loss of 15-42 percent of mammals in North America
7. Climate-caused biodiversity booms and busts in ancient plants and mammals
8. After dinosaurs, mammals rise but their genomes get smaller
9. CU-Boulder study shows 53 million-year-old high Arctic mammals wintered in darkness
10. Climate change driving Michigan mammals north
11. Major international study challenges notions of how genes are controlled in mammals
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Dinosaur-chewing mammals leave behind oldest known tooth marks
(Date:6/9/2016)... 9, 2016  Perkotek an innovation leader in attendance control systems is proud to ... hours, for employers to make sure the right employees are actually signing in, and ... ... ... ...
(Date:6/3/2016)... June 3, 2016 ... Nepal hat ein ... hochsicherer geprägter Kennzeichen, einschließlich Personalisierung, Registrierung und ... der Produktion und Implementierung von Identitätsmanagementlösungen. Zahlreiche ... im Januar teilgenommen, aber Decatur wurde als ...
(Date:6/2/2016)... Perimeter Surveillance & Detection Systems, ... Infrastructure, Support & Other Service  The latest ... comprehensive analysis of the global Border Security market ... of $17.98 billion in 2016. Now: In ... in software and hardware technologies for advanced video surveillance. ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... , June 24, 2016  Regular discussions on a ... take place between the two entities said Poloz. ... Ottawa , he pointed to the country,s ... the federal government. ... said, "Both institutions have common economic goals, why not sit ...
(Date:6/24/2016)... ... June 24, 2016 , ... Researchers at the Universita Politecnica ... in people with peritoneal or pleural mesothelioma. Their findings are the subject of a ... , Diagnostic biomarkers are signposts in the blood, lung fluid or tissue of ...
(Date:6/23/2016)... 2016   Boston Biomedical , an industry ... to target cancer stemness pathways, announced that its ... Drug Designation from the U.S. Food and Drug ... including gastroesophageal junction (GEJ) cancer. Napabucasin is an ... cancer stemness pathways by targeting STAT3, and is ...
(Date:6/23/2016)... , June 23, 2016 Houston ... with the Cy-Fair Sports Association to serve as ... the agreement, Houston Methodist Willowbrook will provide sponsorship ... and connectivity with association coaches, volunteers, athletes and ... with the Cy-Fair Sports Association and to bring ...
Breaking Biology Technology: