Free Republic
Browse · Search
News/Activism
Topics · Post Article

Skip to comments.

'Sabre-toothed squirrel': First known mammalian skull from Late Cretaceous ...
http://www.physorg.com ^ | 03 NOVEMBER 2011 | Provided by University of Louisville

Posted on 11/03/2011 1:42:52 PM PDT by Red Badger

Paleontologist Guillermo Rougier, Ph.D., professor of anatomical sciences and neurobiology at the University of Louisville, and his team have reported their discovery of two skulls from the first known mammal of the early Late Cretaceous period of South America. The fossils break a roughly 60 million-year gap in the currently known mammalian record of the continent and provide new clues on the early evolution of mammals.

Details of their find will be published Nov. 3 in Nature. Co-authors are Sebastián Apesteguía of Argentina's Universidad Maimónides and doctoral student Leandro C. Gaetano.

The new critter, named "Cronopio dentiacutus" by the paleontologists, is a dryolestoid, an extinct group distantly related to today's marsupials and placentals.

"Dr. Rougier and his colleagues truly have made an outstanding discovery of the first really informative skull remains belonging to a key mammalian group," said Rich Cifelli, Ph.D., Presidential Professor of Zoology at the University of Oklahoma and a researcher who, like Rougier, has spent his career discovering and identifying mammal remains.

"The discovery of 'Cronopio' is especially notable because it provides for the first time the whole cranial morphology (form and structure) of a dryolestoid," writes Christian de Muizon, director of the Muséum National d'Histoire Naturelle in Paris in a "News and Views" article in the same issue of Nature.

"Cronopio" was shrew-sized, about 4-6 inches in length, and was an insectivore with a diet of the insects, grubs and other bugs of the time. It lived when giant dinosaurs roamed the earth – more than 100 million years ago – and made its home in a vegetated river plain.

The skulls reveal that "Cronopio" had extremely long canine teeth, a narrow muzzle and a short, rounded skull. "These first fossil remains of dryolestoids … give us a complete picture of the skull for the group," John R. Wible, Ph.D., curator of mammals at the Carnegie Museum of Natural History, said. "The new dryolestoid, 'Cronopio,' is without a doubt one of the most unusual mammals that I have seen, extinct or living, with its elongate, compressed snout and oversized canine teeth. What it did with that unusual morphology perhaps may come to light with additional discoveries… ."

Rougier describes "Cronopio" in a manner that fans of a popular animated movie series can easily understand.

"It looks somewhat like Scrat, the saber-toothed squirrel from 'Ice Age,' " he said.

Cartoon references aside, Rougier, Apesteguía and Gaetano realized almost immediately the importance of the discovery when they located the fossils in 2006 because mammalian skulls are very fragile, small and rarely found.

The skulls were embedded in rock in a remote area of northern Patagonia, about 100 miles from the city of Allen in the Argentinian province of Rio Negro. Removal of the specimens from the rocks encasing them took several years of patient lab work, which eventually confirmed that the skulls were the first of their kind found.

"We knew it was important, based on the age of the rocks and because we found skulls," Rougier said. "Usually we find teeth or bone fragments of this age. Most of what we know of early mammals has been determined through teeth because enamel is the hardest substance in our bodies and survives well the passage of time; it is usually what we have left to study.

"The skull, however, provides us with features of the biology of the animal, making it possible for us to determine this is the first of its kind dating to the early Late Cretaceous period in South America," he said. "This time period in South America was somewhat of a blank slate to us. Now we have a mammal as a starting point for further study of the lineage of all mammals, humans included."

The prospects for further investigation are exciting. "In recent years it has become clear that southern continents hosted their own endemic groups of mammals during the Age of Dinosaurs. But until now, all we have had are isolated teeth and a few jaw fragments … which don't really help much in deciphering broader relationships," Cifelli said. "For this reason, the new fossils provide a sort of Rosetta Stone for understanding the genealogy of early South American mammals, and how they fit in with those known from northern landmasses. Now the burden is on the rest of us to find similarly well preserved fossils from elsewhere, so that the broader significance of Rougier's finds can be fully placed in context."

In addition to conducting research, Rougier teaches anatomy to UofL School of Medicine students and said the discovery extends the knowledge of our lineage.

"This tells us a little more of the full history of our lineage, a very resilient lineage," he said. " 'Cronopio' lived in a completely different world than ours, dominated by dinosaurs and with a different geography; these new fossils give us information on how transient and ever-evolving our world is."

Rougier, a native Argentinian, earned his doctorate at Universidad de Buenos Aires and joined the UofL faculty in 1998 following work at the American Museum of Natural History in New York and Museo Argentino de Ciencias Naturales in Buenos Aires. Funding to support his work came from the National Science Foundation, the Antorchas Foundation and the American Museum of Natural History.

More information: http://www.nature. … re10591.html


TOPICS: Culture/Society
KEYWORDS: archaeology; godsgravesglyphs; iceage; movie; paleontology; sourcetitlenoturl

Photograph by Artist: Jorge Gonzalez / copyright: Guillermo Rougier

Paleontologist Guillermo Rougier, Ph.D., professor of anatomical sciences and neurobiology at the University of Louisville, and his team have reported their discovery of two skulls from the first known mammal of the early Late Cretaceous period of South America. The new critter, named Cronopio dentiacutus by the paleontologists, is a dryolestoid, an extinct group distantly related to today's marsupials and placentals. Credit: University of Louisville

Life imitates art?..........

1 posted on 11/03/2011 1:42:54 PM PDT by Red Badger
[ Post Reply | Private Reply | View Replies]

To: SunkenCiv

Ping!........


2 posted on 11/03/2011 1:43:31 PM PDT by Red Badger (Obama's number one economics advisor must be a Magic Eight Ball.................)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Red Badger

Love that squirrel. Ha, ha,


3 posted on 11/03/2011 1:45:23 PM PDT by org.whodat (Just another heartless American, hated by Perry and his fellow demorats.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Red Badger

Saber tooth or not... it’s a squirrel. My dogs would go after them, too!


4 posted on 11/03/2011 1:46:18 PM PDT by momtothree
[ Post Reply | Private Reply | To 1 | View Replies]

To: Red Badger

They hit that nail on the head, didn’t they?


5 posted on 11/03/2011 1:46:22 PM PDT by GeronL (The Right to Life came before the Right to Happiness)
[ Post Reply | Private Reply | To 1 | View Replies]

To: org.whodat

I believe it was a “squrat”.


6 posted on 11/03/2011 1:47:55 PM PDT by MrB (The difference between a Humanist and a Satanist - the latter knows whom he's working for)
[ Post Reply | Private Reply | To 3 | View Replies]

To: org.whodat

Looks like the artists and filmakers were clairvoyant......


7 posted on 11/03/2011 1:48:03 PM PDT by Red Badger (Obama's number one economics advisor must be a Magic Eight Ball.................)
[ Post Reply | Private Reply | To 3 | View Replies]

To: GeronL

Amazing isn’t it?..........I liked those Ice Age movies...........


8 posted on 11/03/2011 1:49:34 PM PDT by Red Badger (Obama's number one economics advisor must be a Magic Eight Ball.................)
[ Post Reply | Private Reply | To 5 | View Replies]

To: MrB

LOL


9 posted on 11/03/2011 1:49:44 PM PDT by org.whodat (Just another heartless American, hated by Perry and his fellow demorats.)
[ Post Reply | Private Reply | To 6 | View Replies]

To: Red Badger
I'm sure everyone is already thinking that the people that did the artist's rendering from the jaw bones they found just might have been influenced by the artwork in "Ice Age"...?
10 posted on 11/03/2011 1:53:04 PM PDT by MrB (The difference between a Humanist and a Satanist - the latter knows whom he's working for)
[ Post Reply | Private Reply | To 8 | View Replies]

To: org.whodat

“The new dryolestoid, ‘Cronopio,’ is without a doubt one of the most unusual mammals that I have seen, extinct or living, with its elongate, compressed snout and oversized canine teeth. What it did with that unusual morphology perhaps may come to light with additional discoveries… .”

Obviously, it had evolved to eat apples on the other side of the picket fence.


11 posted on 11/03/2011 1:54:36 PM PDT by GladesGuru (In a society predicated upon freedom, it is necessary to examine principles."...the public interest)
[ Post Reply | Private Reply | To 9 | View Replies]

To: Red Badger

Love that movie. The first one. The second one sucked.


12 posted on 11/03/2011 2:06:05 PM PDT by Mercat
[ Post Reply | Private Reply | To 1 | View Replies]

To: Red Badger
http://www.youtube.com/watch?v=XcxKIJTb3Hg
13 posted on 11/03/2011 2:06:55 PM PDT by South40 (Heartless since 1957)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Red Badger

SQUIRREL!

14 posted on 11/03/2011 2:19:39 PM PDT by al_c (http://www.blowoutcongress.com)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Red Badger

put “Sabre Toothed Squirrels” on the list of potential new team nicknames for the University of North Dakota


15 posted on 11/03/2011 2:26:37 PM PDT by Buckeye McFrog
[ Post Reply | Private Reply | To 1 | View Replies]

To: Red Badger

I am just happy that the gazillion squirrel running around outside aren’t saber-tooth squirrels.


16 posted on 11/03/2011 2:46:00 PM PDT by MIchaelTArchangel
[ Post Reply | Private Reply | To 1 | View Replies]

To: Red Badger

I am just happy that the gazillion squirrel running around outside aren’t saber-tooth squirrels.


17 posted on 11/03/2011 2:46:07 PM PDT by MIchaelTArchangel
[ Post Reply | Private Reply | To 1 | View Replies]

To: MIchaelTArchangel

Why is everything from the Ice Age era and before, ‘Saber-toothed’?.........


18 posted on 11/03/2011 2:54:48 PM PDT by Red Badger (Obama's number one economics advisor must be a Magic Eight Ball.................)
[ Post Reply | Private Reply | To 16 | View Replies]

To: Red Badger

Better a saber toothed squirrel than a priapic porcupine.


19 posted on 11/03/2011 2:59:34 PM PDT by Cyman
[ Post Reply | Private Reply | To 1 | View Replies]

To: Red Badger; StayAt HomeMother; Ernest_at_the_Beach; decimon; 1010RD; 21twelve; 24Karet; ...

 GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach
Thanks Red Badger.

To all -- please ping me to other topics which are appropriate for the GGG list.


20 posted on 11/03/2011 3:17:41 PM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
[ Post Reply | Private Reply | View Replies]

Celebrate Jim's Birthday!

Click On The Balloons And Party!

21 posted on 11/03/2011 3:56:27 PM PDT by DJ MacWoW (America! The wolves are here! What will you do?)
[ Post Reply | Private Reply | To 1 | View Replies]

To: al_c

LOL! You beat me to it. Great movie.


22 posted on 11/03/2011 4:11:01 PM PDT by colorado tanker
[ Post Reply | Private Reply | To 14 | View Replies]



And for all you naysayers, complainers, and those
who can donate but won't for whatever petty reason,
DON'T DONATE!! PLEASE DON'T DONATE!!
click here to not donate with gusto!

23 posted on 11/03/2011 4:12:04 PM PDT by TheOldLady (FReepmail me to get ON or OFF the ZOT LIGHTNING ping list)
[ Post Reply | Private Reply | View Replies]

To: Red Badger

Careful guys. Those aren’t walnuts he’s gathering.


24 posted on 11/03/2011 4:12:18 PM PDT by ElkGroveDan (My tagline is in the shop.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: al_c

"The Cone of Shame"...my absolute favorite part. I still laugh just thinking about it!

25 posted on 11/03/2011 4:26:09 PM PDT by rlmorel (The Rats won't be satisfied until every industry in the USA is in ruins and ripe for nationalization)
[ Post Reply | Private Reply | To 14 | View Replies]

To: Darksheare

I’m sure you were involved in this somewhere...


26 posted on 11/04/2011 7:00:59 AM PDT by null and void (MSGT Dean Hopkins USMC (ret) WWII-Korea-Vietnam 11/9/1925-10/22/2011 My hero, my Dad)
[ Post Reply | Private Reply | To 25 | View Replies]

To: null and void

Sabre-toothed squirrels?
Hmm.
Maybe.


27 posted on 11/04/2011 7:20:32 AM PDT by Darksheare (You will never defeat Bok Choy!)
[ Post Reply | Private Reply | To 26 | View Replies]

To: Red Badger

These look like the squirrels that destroyed my bird feeder.


28 posted on 11/04/2011 10:21:05 AM PDT by Hacksaw (I don't hate Mormons. Is that okay?)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Hacksaw

I just watch them spin and fall off.

29 posted on 11/04/2011 10:24:51 AM PDT by bmwcyle (Obama is a Communist, a Muslim, and an illegal alien)
[ Post Reply | Private Reply | To 28 | View Replies]

To: Hacksaw

You must have a very old bird feeder...........


30 posted on 11/04/2011 11:04:43 AM PDT by Red Badger (Obama's number one economics advisor must be a Magic Eight Ball.................)
[ Post Reply | Private Reply | To 28 | View Replies]

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
News/Activism
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson