Tiny 'saber-toothed squirrel' found
These mouse-sized mammals with long teeth lived 94 million years ago, as depicted in this illustration.
November 2nd, 2011
02:00 PM ET

Tiny 'saber-toothed squirrel' found

As suggested in the "Ice Age" movies, some crazy-looking creatures roamed the planet millions of years ago. But there is a large gap in the fossil record from about 60 million to 120 million years ago when it comes to mammals in South America. Where were they, and what did they look like?

Scientists have now discovered a quirky little creature from this time period, as reported in the journal Nature. It's called Cronopio dentiacutus, and it resembles a mouse-sized squirrel with proportionally long teeth, although technically speaking it is neither a squirrel nor saber-toothed.

"The reality of exploration and research can sometimes be as strange as fiction that we see in the movies," said Guillermo Rougier, lead author of the study and professor at the University of  Louisville.

The extinct mammal, which lived 94 million years ago, belongs to the lineage that has given rise to the marsupials and placental mammals that we know today. It's related to all living mammals, including humans in a remote way. It has been extinct for about 60 million years. Rougier and colleagues examined its unique skull.

"It was a lot more primitive than we are with regard to the way in which the skull was put together; the teeth were very primitive," Rougier said. "The skull is about an inch long."

Scientists believe was Cronopio dentiacutus was an insectivore, which is common for small animals today. Their teeth seem to be specialized for cutting and crushing; the large canines of Cronopio dentiacutus could puncture through small insects. To give you some perspective on the size of these canines, imagine if one of your front teeth came down below your chin, Rougier said.

Coronpio dentiacutus lived at the same time as small carnivorous dinosaurs, terrestrial crocodiles and snakes with legs. It inhabited the flood plains of Argentina that is now a desert area in Patagonia, where people live on subsistence farming.

Most mammals were very small, like Coronpio dentiacutus, at that time, said Rougier. It wasn't until big dinosaurs went extinct that mammals grew to be as large as cats and small dogs.

"These were the tiny little guys that would squirrel in between the toes of the dinosaurs trying not to get stepped on."

Post by:
Filed under: Discoveries
soundoff (532 Responses)
  1. this

    Great post. I used to be checking continuously this weblog and I am inspired! Very useful information specially the remaining phase 🙂 I deal with such information much. I used to be seeking this certain info for a very lengthy time. Thank you and best of luck.

    April 2, 2012 at 6:43 am |
  2. Lynette Platek

    Nice Article! Quick read and informative.

    December 12, 2011 at 8:13 am |
  3. Hmmmm

    The teeth might have been for show, in order to find a mate.

    November 11, 2011 at 8:51 pm |
  4. Chris

    Wow, so that's how the little fella in ICE AGE finally ended up! LOL

    November 6, 2011 at 12:34 am |
  5. Bob Row

    If anybody wonder where the name "Cronopio" comes from:

    November 5, 2011 at 3:41 am |
  6. That_Guy

    Think about religion like this: At one time, the ancient Greeks believed in the Olympian Pantheon. This was a time in history when Christianity was not even heard of, let alone recorded. We now regard this as "mythology", but the people of that day saw this as true faith – religion. Image history reversed. Had you believed in Zues today, and the Christians being just another historical footnote, would you see it as "myths" or "legends" of an ancient people? Yes. You would. And when the time comes for EVOLUTION to take place in modern homo-sapians, they will shed the chains of fanatical devotion in lieu of something that, just an idea, makes sense. You saw God? I see pink elephants when I down a bottle of whiskey, but I still know they're not there. Check and mate.

    November 4, 2011 at 10:22 pm |
  7. lilyaqha

    And he comically tried to bring home an acorn ..

    November 4, 2011 at 1:31 pm |
  8. Mac

    It's Scrat from the Ice Age film!

    November 3, 2011 at 8:04 pm |
  9. cody simpson

    pretty awesome

    November 3, 2011 at 5:10 pm |
  10. Sydney

    So i had to do this current event thing for school and i thought this was a good idea. I hope i get an A+! ( or at least a B) =D

    November 3, 2011 at 5:09 pm |
  11. Jack 63

    And all this time I thought Skrat was just an Ice Age cartoon character!

    November 3, 2011 at 4:10 pm |
  12. MaybeAgnosticMaybeNot

    All theological debates can eventually boiled down to 2 possibilities.

    1. In the beginning there was stuff.
    2. In the begininning there was God, and God created stuff.

    Both assume some "thing" whether God or the universe, simply existed. Christians are quick to disregaurd option 1, with no explanation of where God came from. How is it any more rational to assume God just always existed as opposed to the universe?

    November 3, 2011 at 11:30 am |
  13. Griff

    The great thing about the physical laws of the Universe is that they work for everyone whether you believe in them or not. Reality doesn't discriminate nor promote any particular dogma.

    November 3, 2011 at 11:10 am |
  14. /b/ro

    pics or it dident happen.

    November 3, 2011 at 10:52 am |
    • fimeilleur

      I guess the pyramids were never built.... they must have just appeared... after all, there are no pictures of their construction....

      November 6, 2011 at 8:42 am |
  15. r.ortiz

    with teeth like that be glad he not around today.

    November 3, 2011 at 10:46 am |
    • Goddog

      Web... I realize that you are not mocking science here as I said in my last sentence, but to compare the two and say that they are equal is a mockery of science.

      November 3, 2011 at 11:50 am |
      • Webrydr

        Goddog, it comes down to "possible" versus "plausible." Damn near anything is possible on a universal scale. But, what's plausible? Certainty is hard to come by in any cosmological way. Any opinion that ANY of us have is just that. No irrefutable proof, but I lean towards evolution. We've reached the point scientifically where we, as humans, know more about the cosmos than we've ever known. Exo-planets, black holes, quasars, pulsars, neutron stars, red giants and white dwarfs. The details we now know about the moons of Saturn, all 60 some-odd of them. I am grateful to science for revealing thousands of secrets and details. But, I still find no reason to dismiss entirely that it was all "made." Our entire universe may be nothing more than where a couple of "dimensions" rubbed shoulders and the result was the big bang. Or, we could all be a tabletop experiment on some God-kid's playground. I just hope no one pops the bubble.

        November 3, 2011 at 12:23 pm |
      • Goddog

        And I'm not saying that there couldn't have been some creator of it all. But I don't think it serves any usefull purpose to explore that idea whithout any evidence. Do we want creationism taught in school? According to which faith? Just a random statemen "the creator created everything" have a nice day? Beliefs of the supernatural are best left questioned and explored by the individual because science has nothing to say about it.

        November 3, 2011 at 12:37 pm |
      • Webrydr

        I agree that education SHOULD encompass evolution. We have so much more evidence to support the thesis that "things" have evolved over the ages. And, God's not come back to assure us that it's HIS or HER doing, so we cannot know. So, no, creationism should not be the focal point. Evolution is pretty well established. We see it everywhere. But, as I said in my first post on this topic, I don't have a problem with both existing. I'll put it this way: If I were God, I would have tried to look at all the angles, recognized that once something is in place that change is the norm. Whether it's improved or degraded depends on the adaptation. Then, I believe I would have just stepped back and watched. Never mind that it's literally billions of years spent watching. God's got all the time in the universe.

        November 3, 2011 at 2:10 pm |
      • Webrydr

        By the way, Goddog, this conversation has been enjoyable. We've kept it civil, said our pieces, respected the views of the other. What a concept!!! It's been good talking to you.

        Be talkin' to you.........................Webrydr

        November 3, 2011 at 2:15 pm |
      • sumday

        Goddog sometimes the evidence is in the lack of evidence. IE we have no proof of how the Pyramids were built it's still a mystery, yet we don't say they just eroded that way do we? We assume it was humans that built them right? Well as for evidence of a creator I'd say the same is true we look around and see that things have slowly progressed from simply to complex in a balanced and orderly manor then deny anything made it that way. You hold evolution to be the solution, yet I'll point out that evolution does not fit into the scientific method in that it can't be tested, repeated, predicated and does not have a mathematical formula- ALL things that any other theory is required to have before being accepted. We have some observations I admit, and I'm not even saying evolution is wrong. I just don't buy the no design, random accident part. We use math in everything we do and the statistics that everything evolved at the correct time and in balance for millions of yrs are to astronomical to reasonable accept. Looking at "life" it follows a very close pattern of the same things humans do- we started with sail boats, then advanced to steam engines, then to the model T then to sports cars and all of that took planning and design- life follows pretty close to that same pattern going from simple and adding on until we get to humans (we have no known predators or reasons to account for our rise of intelligent). Science clearly states things don't just happen out of nothing- something cause it to happen (action-reaction), as such science has failed to tell us what causes evolution to occur and why it happens in "harmony" with all other life (prey doesn't out evolve the predator, they evolve together). Yes I do think creationism should be taught bc statistically it is much more likely that life was created than randomly happened. No need to bring religion into it, just mention that life has the characteristics of an intelligent design. Personally I look at it like this- we created simple calculators decades ago, then came basic computers, and now look at the computers today- did those programs write themselves or just evolve over time- I mean we are only talking 1 n 0's here- one could argue that over time some 0's turned to 1 and some 1's turned into 0's until the program evolved into an excel program. One of the main contradictions I hear in science is that it is statistical likely that this universe has other life in it (although no proof of that exist), but yet life on earth could not possible be created by anything else other than chance.

        November 4, 2011 at 12:06 pm |
1 2


  • Elizabeth Landau
  • Sophia Dengo
    Senior Designer