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Subscribe to RSSEngineers have used high-speed videos and mechanical gizmos to figure out the mechanics of a cat's drinking style, confirming what most pet owners know already: Cats are way different from dogs.
Dogs drink by dipping their tongues into liquids like ladles. A little pool of water is brought into the mouth every time Fido takes a gulp from the toilet bowl. Cats, in contrast, touch only the curled-back tip of the tongue onto the surface of the liquid. When the tongue is drawn back up into the cat's mouth, a thin column of the liquid is drawn up as well. Then the cat closes its mouth around that column.
The cat-lapping study was published today on the journal Science's website.
Roman Stocker, an engineering professor at the Massachusetts Institute of Technology who specializes in fluid dynamics, admitted in a Science video interview that the research was "somewhat unusual."
M. Pilotto, R. Stocker, P. Reis
How do cats lap? Cutta Cutta shows how it's done.
"What prompted this study of cats was in fact my cat," he said. "I was watching him one morning, three years ago over breakfast, as he was lapping his water. It occurred to me that there was an exciting biomechanics problem hidden behind the commonplace and apparently simple action of lapping."
Researchers spent hours at Stocker's house, waiting for the cat (named Cutta Cutta) to take a drink while the high-speed video camera was rolling. They also analyzed scores of videos of drinking cats -- ranging from recordings of big cats at Zoo New England to cute videos they found on YouTube.
They found that domestic cats average about four laps per second, with each lap bringing in about 0.1 milliliters of liquid. In contrast, tigers, lions and jaguars lap at less than half the rate. In each scenario, the lapping action strikes a balance between the inertia that makes the liquid rise into the cat's mouth ... and the gravity that makes the liquid fall.
"What is remarkable is that cats seem to know about this balance, and lap with a frequency that maximizes this volume ingested," said MIT's Pedro Reis, another co-author of the paper.
To tease out the full story behind a cat's lap, the researchers basically used an artificial cat tongue -- a little glass disk attached to the end of a plunger that dipped down onto the surface of a liquid at an adjustable rate. This gave the scientists a way to quantify how gravity and inertia worked together ... without waiting for Cutta Cutta to decide he was thirsty.
This is the kind of research that sounds as if it came to a conclusion everybody already knows, but Stocker told me these are new discoveries. "I don't think anyone has explained it," he said, "certainly not the balance of forces behind it."
A lapping cat was one of the subjects covered in the Oscar-winning short subject titled "Quicker 'n a Wink," released back in 1940. MIT engineer Doc Edgerton recorded the cat's technique using a high-speed camera, but didn't delve into the detailed fluid mechanics behind it.
Stocker admitted that there's not an immediate practical application to the research, which was conducted with borrowed equipment and no outside funding. But he said the mechanics of a cat's tongue could be adapted for robotic devices that move water around using soft structures (like, say, an elephant's trunk). There might also be some evolutionary lessons to be learned from the differences between the drinking habits of cats and dogs.
The way dogs drink liquids is somewhat messier, Stocker noted. "Part of a cat's face is highly sensitive -- for example, the whiskers. There might be a desire on the part of the cat to keep those dry," Stocker speculated.
But when you get right down to it, the experiment was "purely curiosity-driven," Stocker said.
"Although people may not appreciate that, curiosity is often what motivates science," he said. And the nicest part is that in this experiment, curiosity did not kill the cat.
"The cat is still quite happy," Stocker told me over the telephone. "In fact, he's sitting right beside me now."
Update for 2 p.m. ET Nov. 12: Over at the Not Exactly Rocket Science weblog, Ed Yong goes into more detail about the experiment as well as feline drinking habits. He includes a link to "Quicker 'n a Wink" on YouTube -- a link that eluded me yesterday. You can see the cat-drinking footage at around the 4:40 mark in this clip:
More on cats and dogs:
- How science measures up cats and dogs
- In war of dogs vs. cats, the answer is clear
- Cat calls monkeys to their doom
- Cat vs. dog evolution
In addition to Stocker and Reis, the authors of "How Cats Lap: Water Uptake by Felis Catus" include Virginia Tech's Sunghwan Jung and Princeton's Jeffrey Aristoff.
Connect with the Cosmic Log community by "liking" the log's Facebook page or following @b0yle on Twitter. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.
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For those bashing the "purpose" of this research--ummm how do you think scientific discoveries are made? Yes, I agree this research is not going to find a cure for cancer or solve world hunger, but there are loads of reserach done each day that are meaningless and if one of them can create progress somewhere in our lives then maybe it is worthwhile. Maybe they can discover a way for starving people in Africa to make wells that pull water up more efficiently--I'm just making that up--but you never know and I'm glad scientists have the curiousity to conduct experiments, no matter the "insignificance". Perhaps one day one of those "silly" experiments will find cures for a disease not yet known, or come up with a way to help third world countries survive better, or create the surgery that saves the life of a loved one. I'm not saying that this particular experiment is going to be some earth shattering solution for the world, but I give kudos for those who have the curiousity to ask questions and do something about it, instead of wondering for the rest of their life. And the article says he used his own time and resources.
p.s. my first thought when I read the title was also about a cat lap and I like many was thinking my cat sits in my lap?!? :-)
Or in this case, make advances towards "soft" robotics.
I love how there were physicists who commented on this article more intelligently than I could. It adds something to this news article.
I hate how with just about every article on science and scientific discoveries there are always knuckle draggers who come out saying something to the effect of "Durr! Science is stoopid! Nobody better waste my time trying to figure out how the uneeverse works!" and "Why are we wasting money on science when there are socio-economic problems to take care of?" To the former group I have this to say: If science is stupid then crawl back into your cave (not house, cave) and stop typing on your electrically powered computer in your air conditioned home, eating convenient preprocessed foods, all of which were brought to you by SCIENCE! You're welcome! To the latter group I have this to say: If we wait until all the problems in the world are fixed to start making scientific discoveries and go out into space and study all the little innocuous things in the universe around us, THEN WE WILL NEVER MAKE ANY DISCOVERIES AND NEVER BECOME MORE TECHNOLOGICALLY ADVANCED THAN WE ALLREADY ARE!
The following links would add to the information we need to evaluate this internet article. Research means Research.
http://web.mit.edu/press/2010/cat-lapping.html
http://blogs.discovermagazine.com/notrocketscience/2010/11/11/how-the-cat-that-got-the-cream-then-drank-it/
Improve comments with a little research?
Seriously? Did I miss the article announcing the cure to Cancer, AIDS, Leukemia and all other illnesses? What's so important about the mechanics of how a cat drinks that warrants one cent to be spent on research? Give me a break!
Who are you to tell someone how to spend their money? Who are you to tell people how to spend their personal time? Let's all wait for you to have an extra amount of PERSONAL or DONATED money and let someone else tell you how to spend/use it
I didn't say this experiment would cure diseases-as a matter of fact, I said it wasn't going to. I'm just referring to the fact that scientific discoveries are made because people get curious and try things out and experiment with all sorts of things. Obviously, some experiments are more "crucial" than others, but people on here are bashing the fact that someone conducted this experiment and my point is that it's the process that is important, not necessarily this particular experiment. If you are not intelligent enough to get that, then I totally understand you inability to see any good coming from this article. And please keep complaining and benefitting each and everyday from all the resources we are able to use because some person/scientist got curious and solved/researched a problem.
I'm sure this was funded by a government grant........
I dare you to read the article.
Someone didn't read the article. Please oh please point out where it says public/government was used for this...........and I'll show you were id says that not only were there NOT public/government funds used....but GASP people...wait for it.........VOLUNTEERED their time for this study
Although this article was a bit interesting, my kitty doesn't care how the mechanics of drinking works as long as she can get the water from her bowl to her mouth and neither do I.
We would be better off focusing more on cleaning up and booting out the corrupt elected Corptocaracy on Capitol Hill and trying to actually get our country back on track again.
I am so so happy that this has finally been figured out!!! Yea! How many of my tax dollars did this require? Who was the complete idiot that determined that this was something that any one in the world really cared about?
I'm trying to figure out when you sent this gentlemen your tax dollars, did you read the article?
How much you wanna bet that somehow millions of your tax dollars went to help fund this study.
The article POINT BLANK states that people volunteered their time and there was no public funding. Please read the article before commenting
i learned this in Junior High School (remember those?) about 40+ yrs ago. why is this new and different and why was $$ thrown at this re-research?
Do people even read articles these days? Not a dime was spent on this research.
Knew about this ages ago. The scientist should have googled be fore he wasted money and time 're-inventing the wheel'! I saw a wonderful lecture at MIT by stop-action photography pioneer Dr. Edgerton. He had it in his slides then. It's actually pretty cool to see, too bad this article didn't post a video or images.
One thing you can tell about the volume the cat pulls in is that they don't swallow with every lap. One of my guys who's a very noisy drinker, has a very distinct lap, lap, lap, swallow pattern. So at approximately 0.1ml per lap that means he's swallowing about 1/2 a milliliter per swallow and that sounds about right for the size of his throat.
As I said before, nothing but time was put into this. No money. However, nice point about your cat having a pattern when it drinks.
 Other than being a Fun Fact, what is the importance of this study & how much money was wasted preforming the study?
RE-READ THE ARTICLE.
cats rule. dogz drool.
Since its free...do humans lap more like a dog or a cat-just saying.
And did someone pay anything for this study? Sure it is interesting but dont we have a lot of better things to spend time researching?
RE-READ THE ARTICLE.
It's amazing how many people are trolling on this article and complaining about how much money was wasted on it, when they obviously didn't even bother to read the article or any previous comments before their own.
"the research, which was conducted with borrowed equipment and no outside funding"
As to who cares? I do! As do many other curious people who have cats, like animals, or just like learning new things.
I mentioned this article to my Cat and the only answer that I got in response was =^';'^= Meow
if you like cats, here's a short i made on super 8 film called "Domesticated Kingdom"
http://www.youtube.com/watch?v=4GE3iXLdD0I
Can't anyone ever just read an article just for fun? Can't you just for a change say "oh, that's cool?" or "I never thought about that?" or even just chuckle and go on to the next story?
My first thought was first, hmmmmmm, my cat's lap, where exactly is a cats lap ... then it was "oh, now I know why one of mine dips her paw and then licks it ... more water at one time!"
So much drama for a story!
As to why is this research important? Not only does the smallest advances help for future research projects, but the students partcipiating in this study learned more about basic research. Now they can go do more "helpful" experiments.
Apples dropping helped discover gravity, which of course doesn't help at all in todays world. Even the simplest things can end up providing an extreme amount of use years later.
And they had to get this approved by the MIT board since MIT students aided in researching this problem. And if there weren't any projects currently being done with the equipment, and a collegue or friend owned it, I doubt that it would have been a problem to use it. Yes, probably a little money went into the project, but it sounds like the researcher put in his own to cover the costs, and at most MIT gave him some minor amount of money since he was exposing students to research.
Research is research. In many ways some of the greatest discoveries were made by piecing a lot of previous research together. eg. the discovery of DNA and it's structure.
What about a cat like mine... he drinks from the dog water bowl with his paws. He cups his front paw and lifts to his mouth... very strange.. but he seems satisfied...:)
Heheheh, maybe he thinks its disgusting cuz the dog drinks from it. Kinda like changing a babys poopoo diaper, we turn up our noses or hold our breathe but we still got to do it.
Catnip - 13 - You are among a group of quite a few whose cats stick their paw in the water dish and then lick their paw, at least 7 or 8 other posters have said the same thing as you. Including me, I guess my cat Jethro isn't quite as unique as I thought him to be. It is very interesting to see just how many cats drink this way.
So water tention is the big "SECRET" good fracking grief give me a break! Woo hoo I feel like Isak Newton suddenly the secrets of the universe are revealed all bow down and worship me!
Maybe all of you should go to the dog shake article. I would have not considered the "practical" uses for this research either, but they have some possible ideas. Maybe you can come up with others for the cat lap experiment
Geesh....all of us cat owners have known this for a long time. Just why was this subject studied by someone and not just asked of one of us? oh well....another pork bellied grant of our tax dollars at work I would imagine.
RE-READ THE ARTICLE.
Cap lapping, huh? New discovery? Secret? Revealed? Hardly. Cat lapping tactics and the attending physical laws have been known for decades. The only thing changed is the photography. It's better.
I don't know but the last thing I heard was that the country is about bankrupt but they can spend money on things that don't matter to anyone like how cats and dogs drink? Why not keep that money and give it to someone who could really use it like the national debt
RE-READ THE ARTICLE OH BRILLIANT ONE.