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Genetically Engineered Mouse is Not Scared of Cats
Gary writes "A team from the University of Tokyo has genetically engineered a mouse that does not fear cats. By tweaking genes to disable certain functions of the olfactory bulb (the area of the brain that receives information about smells directly from olfactory receptors in the nose) the researchers were able to create a 'fearless' mouse that does not try to flee when it smells cats, foxes and other predators. 'The research suggests that the mechanism by which mammals determine whether or not to fear another animal they smell -- and whether or not to flee -- is not a higher-order cerebral function. Instead, that decision is made based on a lower-order function that is hardwired into the neural circuitry of the olfactory bulb.'"
So he's fearless if he smells a predator. What if the mouse sees a cat running full speed at him?
I can't find myself fearing fearless mice. Why? Because there was most likely a very good reason for the mice that they are afraid of cats and large things that can eat them... I just can't seem to worry about these things getting loose and breeding in the wild.
It's sort of like the fear of spiders, snakes, bears, and large cats. There are very valid reasons for humans to be naturally afraid of things that can kill/harm and maybe eat us.
Whatever function is triggered is being disabled by the removal of the SMELL capacity, not the FLEE capacity. That part of the mouse's brain that is responsible for interpreting the smell of a predator is probably still working fine, but is just not being stimulated because they have disabled the SMELL part.
Not news. They already engineering ones that do not fear my wife. It was only a matter of time.
Another team took the opposite approach and genetically engineered many people I know to have an irrational fear of global warming.
I'm glad their tackling this fear things from both ends.
"If you want to improve, be content to be thought foolish and stupid." - Epictetus
Once we have this treatment available for humans, Slashdotters will no longer be afraid of women!
In other news, Doraemon is still scared of mice.
In Soviet Russia, Jesus asks: "What Would You Do?"
There's ample prior art.
Welcome to the Panopticon. Used to be a prison, now it's your home.
The company that made mouse an integral part of personal computer also makes all the OSes named like panther, tiger and leopard. So I am not surprised the mouse does not fear the cat. Aren't mice intelligently designed by Steve Jobs?
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
This mouse is often seen wielding a large mallet.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
these results to man. for unlike the lower animals, we are motivated by higher mental orders of conscience and reason. of course, some wankers will come along and say that we are also help captive to these lower impulses. but i say-
mmm... who's cooking brownies?
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
The sense of smell is a big deal in the way predator and prey interact. For example, without a doubt the best way to get rid of the squirrels in your attic is to squirt just a small amount of fox urine fox urine up there. Just a few drops around your attic ladder opening will have those little farts on the run and gone within a day. Then plug up whatever holes originally allowed them to get up there and the problem is solved.
One caution: I've found that it only works once. If you don't seal up those holes, the squirrels come back and the second application doesn't work. Maybe you just need fresh urine. But no matter the reason, don't put off the soffet repairs (or whatever work you need to do) after scaring them away.
No, what really freaked the cat out was when the mouse tried to mate with it...
Seven puppies were harmed during the making of this post.
It's sort of like the fear of spiders, snakes, bears, and large cats. There are very valid reasons for humans to be naturally afraid of things that can kill/harm and maybe eat us. It's not the mice I'm afraid of, it's the supersoldier program to which this could be applied.
Of course, I'm not entirely sure they took out the mice's fear as much as their ability to detect the smell... maybe that's in TFA, I'll go see.
You can't take the sky from me...
My cat doesn't have an eat mouse reflex - it's evolved into a "bat the mouse around for two hours until it dies of a heart attack, and then leave it somewhere that Food Bringing Slave can step on it!" reflex ...
A feral cat wouldn't have those issues, it would have slaughtered that mouse the second it didn't run fast enough. Yours is just a pussy.
Maybe someone pointed this out already, or perhaps I am just a bozo...
If a mouse's sensorium is determined a great deal by its sense of smell... and you disable that sense of smell... its "higher-order cerebral functions" would be impaired because they would not be getting the input they require to make decisions. How can you conclude that fear in mammals is related to the oflactory sense? Other mammals may use other senses to a larger degree.
To me, this seems like the old joke about the bad scientist who concluded that a frog with all its legs removed becomes deaf because it doen't jump when he yells at it.
http://en.wikipedia.org/wiki/Toxoplasmosis
"It has been found that the parasite has the ability to change the behavior of its host: infected rats and mice are less fearful of cats"
http://www.dieblinkenlights.com
I've been reading Slashdot daily for nearly a year. I don't usually post, I'm more interested in what the experts have to say. I'm getting a little fed up with the stupidly over used comments though. There are places (lots of places) online where you can go to say these things and get a laugh. Leave Slashdot as an intellectual retreat :)
We're engineering our mice to be stronger... faster... smarter... better... The new super-mouse will be able to take on a cat... and WIN! Immortality for mice is just around the corner. This is not an evolutionary dead end! This is the future of life as we know it!
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
This is developing into a new field of study known as Epigenetics. Environmental factors, such as diet and exposure to toxins can activate or deactivate genetics.
Read more at:
Discover Magazine, November 2006
Wikepedia: Epigenetics.
Science Magazine
It seems the only way evolution could explain this is by saying that the vast-majority of mice without this gene were promptly eliminated by cats and taken out of the gene pool.
Not at all.
Consider a population of pre-mice, without the gene, that are reasonably adept at avoiding predators for other reasons -- camouflage, fast, good hearing, whatever. Then some sub-population of these critters acquires this gene. Said sub-population becomes much more adept at avoiding predators, and tend to out-survive (and hence, out-reproduce) those without it. Perhaps later, since that gene is so effective, the biological cost of the other avoidance factors (camouflage, hearing, speed etc) outweighs the advantage they confer, and they fade from the population, or perhaps not. Probably in the pre-smell avoidance gene days, cats and other predators were on average slower, and the predator population slowly gets faster as the quick ones outcompete the slow ones.
Likewise for the smell of other predators. But that would imply that there was initially an enumerated list of odors
Not at all.
This assumes that not only do all predators smell different, but that the odor-causing chemical in each species is completely unrelated to all others. This is highly improbable. More likely the odorant chemical is identical or very nearly so in mouse-predator species, probably some byproduct of digesting and metabolizing mouse (and other rodent) proteins. (Consider also that there are only a few different families of mammalian rodent predators - felis, canis, mustelidae - and this smell aversion probably doesn't work for snakes or owls.)
-- Alastair
You have some wrong implicit assumptions there.
1. First of all, you seem to assume that the gene that recognizes "cat smell" just appeared out of nowhere. That's not the case. Even one cell organism have various degrees of analyzing the chemistry around them, because that's such a damn useful signal. Primitive sea organisms had some kind of sense of smell long before they even evolved eyes. Move out of the water and even primitive insects have a lot of smell sensors on their antennae.
So by the time they evolved to a mouse, it _already_ had a very sophisticated sense of smell, and the brain power to process, analyze, categorize and react to smells.
2. Even being sensitive to a very specific cat protein, if they have such cells, is easily explainable by mutation. Binding to some other mollecule is what proteins _do_. There are thousands of enzymes in your body that, basically, interact with just a single chemical, repeatedly. That's how you can process fructose (corn syrup) into glucose: an enzyme just breaks one molecule after another.
Heck, you even have cells in your immune system which _deliberately_ mutate until they make a protein that can match another protein. There's an enzyme whose sole role is to junk a random codon (think: byte) of DNA, so the DNA repair mechanisms would kick in, and occasionally get it wrong. And given enough time eventually you end up with a gene, by sheer random chance, that exactly matches the capsid of a new virus or some membrane proteins of a new bacteria. Amazing (and amazingly inefficient, if some God designed it), but there you go: making a protein that matches another protein is nothing new.
So given billions of billions of individuals, over millions of years, it wouldn't be surprising at all if some mice accidentally evolved noses perfectly attuned to cats. It could even start with a mouse with allergy to, say, FEL-D1 (a protein all felines have, and which is triggers cat allergies in some people), and it ended up giving his kids an advantage. From there it could evolve from mere allergy to panic attack, because the more scared you are of a cat, the more survival chances you have.
3. It's all chemistry, and there aren't that many mediators that regulate the moods. Triggering, for example, a panic just involves giving the right chemical signal.
And in the case of mice and rats, it's just that. There is no higher logic circuit in deciding to run from a cat. The smell just literally gives them a severe, illogical panic attack. When they test anxiety medication on rats, it's quite common to use cat urine to give them a reflex panic attack, then see if your drug calms them down. The running away is just the result of that panic, nothing more.
So don't think there's some complex coding involved. Even a simple enzyme could do just that: process the protein or chemical specific to cats, into the chemical that puts the brain into panic mode.
Plus, the way proteins work is rarely orthogonal coded. A small change here, produces an unrelated effect there. Some circuit in the brain could have simply been accidentally mis-wired to relay the signal along the wrong path, or release the wrong mediator.
At any rate, so a proto-mouse got a severe panic attack at the smell of a proto-feline, just because of a mutation, and it ended up saving his/her life. Then the kids inherit it and are the ones who have less of a chance of getting eaten.
4. Precisely the fact that it _doesn't_ react to other predators, should probably tell you that there is no higher intelligence or design at work.
The mice simply evolved to deal with the _existing_ threats, not to be the thing that can universally deal with any imaginable carnivore. Threats that actually existed and killed some of the mice, were evolutionary pressures. The mice which could deal with them, were more likely to survive, so those genes got passed on. The threats that they didn't have to deal with, _weren't_ evolutionary pressures and made no difference. So if a mouse-e
A polar bear is a cartesian bear after a coordinate transform.
I think that although your post is humorous, it's also incorrect. There was a nature show on TV with a young antelope and two lions. The antelope had no fear of the lions, and the lions dodn't know how to act, although they did wind up eating it in the end.
mcgrew's razor: Never attribute to stupidity that which can be explained by greedy self-interest