Subscribe free to our newsletters via your
. 24/7 Space News .

Subscribe free to our newsletters via your

Extinct otter-like 'marine bear' might have had a bite like a saber-toothed cat
by Staff Writers
New York NY (SPX) Mar 02, 2016

This image shows lower jaw stress models of Kolponomos newportensis (left) versus Smilodon fatalis during an anchor bite. Image courtesy AMNH/J. Tseng, C. Grohe, J. Flynn. For a larger version of this image please go here.

New research suggests that the feeding strategy of Kolponomos, an enigmatic shell-crushing marine predator that lived about 20 million years ago, was strangely similar to a very different kind of carnivore: the saber-toothed cat Smilodon.

Scientists at the American Museum of Natural History used high-resolution x-ray imaging and computerized biting simulations to show that even though the two extinct predators likely contrasted greatly in food preference and environment, they shared similar engineering in jaw structure, suitable for anchoring against prey with the lower jaw and forcefully throwing the skull forward to pry loose its food. The study is published in the journal Proceedings of the Royal Society B.

The only known specimens of Kolponomos - primarily skulls and teeth of two species - were recovered from ancient marine deposits along the Pacific coast of Oregon, Washington, and possibly Alaska. Because of its peculiar morphology and the small number of fossils, the animal's place in the evolutionary tree remains a mystery.

"When Kolponomos was first described in the 1960s, it was thought to be a raccoon relative," said Camille Grohe, a National Science Foundation and Frick Postdoctoral Fellow in the American Museum of Natural History's Division of Paleontology and a co-author on the new paper. "But later research on the skull base led some to think it might be a seal or a bear relative instead, and studies of its teeth show that they are very similar in both shape and wear to the teeth in sea otters."

Sea otters pry their prey - hard-shelled marine invertebrates like clams and mussels - off of surfaces using their hands and rock tools, then crush the shells with their teeth or against their chests, again using tools.

By studying Kolponomos fossil material from the National Museum of Natural History in Washington, D.C., and comparative specimens from the American Museum of Natural History, the research team originally set out to test if the extinct predator used otter-like shell-crushing to eat. But the scope of the research expanded after Grohe's collaborator Z. Jack Tseng noticed something curious in parallel to work he was conducting on the saber-toothed cat Smilodon.

"I started seeing a great deal of similarity between the jaws of Kolponomos and Smilodon," said Tseng, a National Science Foundation and Frick Postdoctoral Fellow in the American Museum of Natural History's Division of Paleontology and the lead author on the new paper.

"Both of them have a distinctive profile with a deep jaw bone that tapers off toward the back, and both have an expansion of the mastoid processes and the skull's back surface, suggesting large attachment sites for muscles that let the animal move its head powerfully but with control. We definitely didn't expect to bring Smilodon into this study of feeding in a clam-eating marine carnivore, but that's what we ended up doing."

At the Museum's Microscopy and Imaging Facility, the researchers used computed tomography (CT) to scan the skulls of Kolponomos and six other carnivores: Smilodon, grey wolf, sea otter, river otter, brown bear, and leopard. They then used computerized methods to build sophisticated biomechanical models to look at how efficiently the animals could perform various bites, including the jaw-anchored killing shear-bite that is characteristic of saber-tooth cats.

They found that the jaw mechanics of Kolponomos and Smilodon are more similar to each other than to any of the other animals in the study, pointing to a unique feeding strategy in addition to the previous idea that Kolponomos might have crushed its prey like sea otters do today. Taken together, the researchers suggest that Kolponomos might have pried prey off of rocks with its lower jaw, swung its skull forward to dislodge it, and then crunched it with its chewing teeth.

"Our biomechanical data show that the chewing bites of sea otters and Kolponomos are not very similar," Tseng said. "They probably still have an overlapping diet based on tooth wear, but their evolutionary solutions for getting to those hard-shelled animals are dramatically different."

The researchers stress that this finding does not imply shared ancestry between Kolponomos and Smilodon, but rather an intriguing case of convergence - the independent evolution of similar traits.

"This innovative study, showing unexpected feeding similarities between such wildly distinct carnivores, could only happen by applying new technologies to understand specimens from some of the world's greatest archives of ancient life," said John J. Flynn, a curator in the Museum's Division of Paleontology and Dean of the Richard Gilder Graduate School, also an author on this paper.

This work was funded by the U.S. National Science Foundation grant # DEB-1257572 and the American Museum of Natural History's Frick Postdoctoral Fellowships.

The authors have dedicated this study to the memory of Museum artist Chester Tarka, who illustrated Kolponomos newportensis. Tarka, a decorated Army veteran of the Normandy Invasion and Battle of the Bulge in WWII, passed away recently at the age of 96 and was buried with military honors in Saratoga, New York.


Related Links
American Museum of Natural History
Explore The Early Earth at

Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks DiggDigg RedditReddit GoogleGoogle

Previous Report
The sponges strike back
Moscow, Russia (SPX) Mar 01, 2016
Reaggregation of marine sponges' cells helped the scientists to come closer to understanding of the origin and early evolution of multicellular animals.The work was published in Journal of Experimental Zoology Part A: Ecological Genetics and Physiology. Andrey Lavrov and Igor Kosevich, MSU biologists, researched the ability of the cells of marine sponges (Porifera) to reaggregation - a pro ... read more

New Lunar Exhibit Features NASA's Lunar Reconnaissance Orbiter Imagery

NASA releases strange 'music' heard by 1969 astronauts

NASA chooses ASU to design and operate special satellite

Chinese scientists invent leak detection system for moon exploration

Jarosite in the Noctis Labyrinthus Region of Mars

Trace Gas Orbiter and Schiaparelli are joined

Footprints of a martian flood

Russia plans return to Mars, Moon despite money woes

Tools and Talent at Michoud to Complete SLS Core Stage Welding in 2016

Orion Simulations Help Engineers Evaluate Mission Operations for Crew

Orion Test Hardware in Position for Solar Array Test

NASA Space Program Now Requires Russian Language

China to launch second space lab Tiangong-2 in Q3

China's moon lander Chang'e-3 enters 28th lunar day

Staying Alive on Tiangong 2

China Conducts Final Tests on Most Powerful Homegrown Rocket

Scott Kelly returns to earth, but science for NASA's journey to Mars continues

Orbital ATK Completes OA-4 Cargo Delivery Mission to ISS for NASA

Send your computer code into space with astronaut Tim Peake

Black Mold Found in Cargo Prepared for ISS, Resupply Mission Delayed

Arianespace Soyuz to launch 2 Galileo satellites in May

SpaceX postpones rocket launch again

Russian rocket engines ban could leave US space program in limbo

SpaceX warns of failure in Wednesday's rocket landing

Imaging Technique May Help Discover Earth-Like Planets Around Other Stars

Newly discovered planet in the Hyades cluster could shed light on planetary evolution

Imaging technique may help discover Earth-like planets

Longest-Lasting Stellar Eclipse Discovered

Research demonstrates that air data can be used to reconstruct radiological releases

Eco-friendly food packaging material doubles shelf-life of food products

Virtual reality is next as smartphone sales slow

Crystal and magnetic structure of multiferroic hexagonal manganite

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.