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Giant African Rat Kills With Poisonous Mohawk

samzenpus posted more than 3 years ago | from the T-approved dept.

Idle 97

thebchuckster writes "The African crested rat has been known to kill local dogs, but researchers have just figured out how. After eating the 'poison-arrow plant,' the over-sized rodent stores its poison-laced spit in special hollow hairs in its mohawk. Then, when a predator grabs the rat, the animal gets stung with the poison and spit-tipped hairs which can sicken and kill."

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Punk (2)

ctrimm (1955430) | more than 3 years ago | (#36978970)

Now that's punk.

Punk (1)

hoboroadie (1726896) | more than 3 years ago | (#36979200)

Another Marvel character, I thought.

Re:Punk (1)

Abreu (173023) | more than 3 years ago | (#36979306)

More like a randomly generated Gamma World character

"Poisonous / Ratman"

Re:Punk (0)

Anonymous Coward | more than 3 years ago | (#36981934)

I thought R.O.U.S.

Re:Punk (0)

cfalcon (779563) | more than 3 years ago | (#36979350)

No, that's trendy.

Re:Punk (1)

flyneye (84093) | more than 3 years ago | (#36979748)

We're breeding it into our next gen Marine stock. Semper Fi!

Re:Punk (-1)

Anonymous Coward | more than 3 years ago | (#36979580)

IThank God niggers have curly hair, which precludes the formation of the requisite hairstyle , or we'd be in deep shit.

On second thoughts, it requires too many complicated interdependent actions for a darky to perform reliably. No need to worry, folks.

Re:Punk (1)

hairyfeet (841228) | more than 3 years ago | (#36983558)

Yeah what idiot in the animal kingdom gonna mess with this baaaad mofo, he's a rat with a mohawk! The fact that its poison just shows he's a rat that takes NO shit from nobody. I bet he's got a little switchblade to, just ready to stab your ass if you piss him off. he's a baaaad little rat dude!

Re:Punk (1)

hesaigo999ca (786966) | more than 3 years ago | (#36984832)

Now that's Spunk ....there ...fixed that for you.

Is this tool use? (2)

es330td (964170) | more than 3 years ago | (#36978996)

I realize it isn't termite fishing with a stick like monkeys do but it is certainly manipulation of an object for the animal's benefit.

Re:Is this tool use? (1)

blair1q (305137) | more than 3 years ago | (#36979412)

Only if the rat bought the quills at the Home Depot.

Re:Is this tool use? (2)

Chris Burke (6130) | more than 3 years ago | (#36979532)

I wouldn't call chewing bark tool use. Nor grooming. It's "manipulation" only in the broadest sense of "using", but eating food is "using" an object for the animal's benefit.

Regardless of semantics, it is doubtful this is a sign of intelligence (which tool use is usually taken to suggest).

However it is a sign of awesome. Punk rock murder rats? Hell yes.

Re:Is this tool use? (1)

shugah (881805) | more than 3 years ago | (#36980188)

The article says the behavior seems to be hardwired into the rat's brain; that is, it's instinctive.

Chimpanzees have to be taught to fish for termites with a stick. Chimps don't have any evolutionary adaptation specific to fishing for termites (an opposable thumb is not specific to this behavior or even to primates). My understanding is that some populations of chimps (and even individuals within a population) learn / exhibit this behavior, others don't.

The giant crested rat chews poison bark and grooms its specially adapted crest hairs instinctively. Rats don't need to be taught to chew, or to groom. While it is a little more involved (requires a specific behavior or chewing and grooming) it is very similar to a poison dart frog absorbing, concentrating and sequestering in their skin, toxins from centipedes, ants etc. that they eat. My guess is that all giant crested rats, in an environment where this tree is native, would exhibit the same chewing and grooming behavior.

Re:Is this tool use? (0)

Anonymous Coward | more than 3 years ago | (#36982750)

Punk rock murder rats

Now there's a great name for a band :D

How did this evolve? (3, Interesting)

improfane (855034) | more than 3 years ago | (#36979006)

It does make you wonder how something so specific could evolve, the relationship between a poisonous plant and then the distribution mechanism.

I know that when I eat certain herbs, I sweat them out and smell strongly of that herb whereas other people I know are fine. I wouldn't be surprised if that is related, the rats that could not sweat out the chemicals died, those that could survived, the ones who sweated through barbs fared even better. Do animals that disperse poison even know it's a defensive mechanism?

How can they evolve that knowledge? Or is it aggression that is evolved too? A poisonous rat that is passive will probably not survive (it might still get eaten if it kills its predator) whereas one that is aggressive can attack its predator before it eats it.

What do you think?

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36979044)

I'd say stop eating those herbs.

Re:How did this evolve? (-1, Troll)

Anonymous Coward | more than 3 years ago | (#36979152)

I have to post this as "A.C." because if I use my real ID, the retribution is intense!

Because the THEORY of Evolution is merely a man-made attempt to push God out of their lives. This is yet another example of Intelligent Design. Anyone who examines the INCREDIBLE COMPLEXITY of living things should be able to realize that these are examples of intelligent design. Symbiotic relationships, even moreso.

Let the immature ranting and name-calling begin... sigh. So much for "open minds".

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36979246)

I'm having a hard time telling whether this is a troll, or a joke or what.

Re:How did this evolve? (1)

Chris Burke (6130) | more than 3 years ago | (#36979602)

I'm having a hard time telling whether this is a troll

Are you really?

Re:How did this evolve? (1)

retchdog (1319261) | more than 3 years ago | (#36991300)

unfortunately, yes.

Re:How did this evolve? (1)

Chris Burke (6130) | more than 3 years ago | (#36991622)

Well let me help you out -- regardless of what else that post was, whether earnest or in jest, it was definitely a troll.

Re:How did this evolve? (1)

furbearntrout (1036146) | more than 3 years ago | (#36981750)

It's called Poe's Law [wikipedia.org] . No matter -- flamebait and troll are both -1.

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36979266)

Because the THEORY of Evolution is merely a man-made attempt to push God out of their lives.

You're in my life more than God is. At least you communicate with me.

Re:How did this evolve? (2)

rubycodez (864176) | more than 3 years ago | (#36982368)

But he can never hate you as much as God does, sinner.

Now repent and send me money for telling you so.

Re:How did this evolve? (1)

NiceGeek (126629) | more than 3 years ago | (#36979330)

Look up what a scientific theory entails and maybe you can post without someone calling you an imbecile. Intelligent Design isn't even a decent hypothesis, let alone a theory. You're the one with a closed mind.

Re:How did this evolve? (1)

Anonymous Coward | more than 3 years ago | (#36979378)

I'd like to encourage you to watch Professor Kenneth Miller of Brown University speaking at Case Western Reserve University [youtube.com] . Every irreducible complexity argument has been debunked, and if you were to argue that this rat's unique ability is evidence of irreducible complexity, I'm sure it would be too. There have been many other instances that were much more convincing than this rat, all of which have been explained to my satisfaction and the satisfaction of most of the scientific community. Some of these very compelling instances are beautifully explained by Professor Miller in this video.

Re:How did this evolve? (1)

Heed00 (1473203) | more than 3 years ago | (#36979496)

Right, so here we see the mighty argument from design -- "It's complex therefore it had a designer."

It's a complete non-sequitur. One simply doesn't follow from the other. Designers can design simple things and complex things can arise without a designer.

You complain about open minds but provide no actual argument -- you do what everyone who has ever put forward the argument from design or one of its variants does -- you go, "See, see this complex thing! Doesn't that blow your mind? Yep, it just makes sense that something made it, right? Right?" And you do that because there is no actual argument to make -- it's just a trick of the light.

Re:How did this evolve? (1)

Macgrrl (762836) | more than 3 years ago | (#36979556)

I blame Douglas Adams, the Bablefish proof is obvious prior art for the concept of Intelligent Design.

With a bit of luck they will all get knocked down at a zebra crossing. :P

Re:How did this evolve? (1)

Heed00 (1473203) | more than 3 years ago | (#36979608)

Hehe.

Yeah, but the Babelfish proof actually disproves god and he vanishes in a puff of logic. ;) Wish these ID'ers would do the same.

Re:How did this evolve? (1)

Xenx (2211586) | more than 3 years ago | (#36979498)

Because the THEORY of God is merely a man-made attempt to explain what we don't understand and control society.

Everyone has their own choice to make on the matter.

Re:How did this evolve? (1)

Translation Error (1176675) | more than 3 years ago | (#36979502)

Because the THEORY of Evolution is merely a man-made attempt to push God out of their lives. This is yet another example of Intelligent Design. Anyone who examines the INCREDIBLE COMPLEXITY of living things should be able to realize that these are examples of intelligent design. Symbiotic relationships, even moreso.

Yes, the theories all those scientists have come up with, pieced together from many data and refined time and time again to account for new data, has nothing against your assertion backed by "BECAUSE I SAID SO."

Really, why do they even bother scrounging around in the dirt to come up with some absurd theory of 'evolution' when any fool can see--wait, that sounds familiar somehow...

Re:How did this evolve? (1)

M0j0_j0j0 (1250800) | more than 3 years ago | (#36979720)

Because the THEORY of Evolution is merely a man-made attempt to push God out of their lives. Let me fix this for you, Because the THEORY ( Intelligent Design) is merely a man-made attempt to push ( Science ) out of their lives. There, now you have it :)

Re:How did this evolve? (1)

rubycodez (864176) | more than 3 years ago | (#36982432)

I see your Intelligent Design in the puddles outside my house. There is no way those puddles could so perfectly fit into those marvelously complex holes, without a Divine Puddle Maker lovingly creating and crafting them so. And when a puddle dies in the hot sun, it rises into puddle heaven and is born again to rain back. Praise the DPM! No, not Double Penetration. Mouth, you filthy heathen....

Re:How did this evolve? (2)

Genda (560240) | more than 3 years ago | (#36984136)

That's because there are a lot of folks out there who have little tolerance for other people's belief. By the way that goes both ways. There were people burning each other over toasty coals because they disagreed on the finer points of Jesus, long before science nerds heckled the faithful. In fact the holiest church in all of Christendom, the Church of the Holy Sepulcher, has for generations had its door locked and unlocked by a Muslim family because the various sects of Christianity don't trust each other enough to give any one the keys. That my friend is being human.

So there is faith and then there's science. One is based on the unexplainable, and the other on empirical fact and data. The reason people get pissy about ID, is because its a belief looking for justification. That's really bad science, and when they catch scientists doing that (which happens every so often) they get their hands slapped and lab coats handed to them.

We now have so large a body of evidence, from so many fields (biology, material science, computer science, biiochemistry... it goes on and on) that we can actually point right at evolution as it happens/happened both micro and macro-evolution. Intelligent Design simply isn't necessary. If you choose to believe in God, you should be all the more joyful at your Lords cunning and brilliance to create space time that would result in atoms such that they can assemble themselves into mountains, or stars, or people. Its like epicycles, as long as you assume the earth is the center of the universe, you have to go through all kinds of ridiculous gyrations and complications to account for the behavior of the universe. The instant you give up trying to make it fit your pictures and just appreciate it the way it is, natural order arises and is self evident.,

I have no problem with people who believe in God. Science suggests a God isn't necessary for this universe to happen the way it happens/happened. Maybe God doesn't have an ego problem? That's where the faith comes in, eh?... Bon Apetite.

Re:How did this evolve? (1)

tehcyder (746570) | more than 3 years ago | (#36984384)

I have to post this as "A.C." because if I use my real ID, the retribution is intense!

Hold on a sec, if real Intelligent Design is yours, you must be God. Now there's a first, the supreme deity posting on slashdot. Although you'd expect Him to have a slashdot account so that He can do some proper smiting to us unbelievers.

Re:How did this evolve? (0, Troll)

Anonymous Coward | more than 3 years ago | (#36979268)

Why, it was clearly designed by a benevolent creator that hates dogs and has a sense of humor. My personal best guess as to the relevant deity is Ifni, Goddess of Random Chance. Ifni works sort of like the infinite improbability drive -- by making things that are enormously improbable -- like electing George Bush (a certified idiot) president of the most complicated country on Earth during one of the most delicate of historical times -- happen anyway. So when you see Sarah Palin elevated from being a failed cheerleader in a tiny high school in a distant and underpopulated state to being a vice presidential candidate, possibly a presidential candidate -- one who, mind you, thinks that Paul Revere rode out to warn the British that the minutemen were coming and is willing to argue on national television with anybody who disagrees -- you can just nod your head and say, wisely -- "Yeah, African Crested Rats and Sarah Palin. Oh, Ifni is at it once again..."

rgb

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36979298)

How can they evolve that knowledge

This is the wrong way to think about it. Organisms do not pro-actively evolve with a goal in mind. They evolve by developing a random mutation that ends up giving a breeding advantage.

The answer to your question is always "dumb luck," even if you can think of a rational reason to explain why the mutation is beneficial, and why a rational being would want to evolve the trait. Again, evolution is not driven by desire.

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36979484)

Your understanding of evolution is overly simplistic and ignores recent evidence of non-DNA traits being passed down over multiple generations. It is not always dumb luck that determines traits of your progeny.

Re:How did this evolve? (1)

JeanInMontana (2020420) | more than 3 years ago | (#36979310)

It's a basic instinct to survive, I doubt the rats are aggressively using anything. Predator grabs rat to kill and the poison is released.

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36979434)

It does make you wonder how something so specific could evolve, the relationship between a poisonous plant and then the distribution mechanism.

...

Yes, I know you're not making it directly, but...

OMG how I HATE that line of creationist argument.

"Just because I can't figure out how it could happen, God must have done it!"

As if the possibilities of what can happen in the universe are bounded by what one credulous person can think of.

Re:How did this evolve? (1)

willy_me (212994) | more than 3 years ago | (#36979440)

How can they evolve that knowledge? Or is it aggression that is evolved too? A poisonous rat that is passive will probably not survive (it might still get eaten if it kills its predator) whereas one that is aggressive can attack its predator before it eats it.

In this example, aggression is not required. If an animal is killed but also kills the predator in the process, then the DNA of that animal will be more likely to survive via the increased likelihood of survival for it's relatives due to the death of a local predator.

For example, mother and baby rats get attacked by a fox. One baby rat dies along with the fox. Now the mother and remaining babies have an increased chance of survival. Because they all share similar DNA, the DNA traits that killed the fox survive.

Re:How did this evolve? (1)

Darth_brooks (180756) | more than 3 years ago | (#36979520)

People seem to think evolution is akin to this situation: "I was walking down third street just past the bank when I looked down and found a 1999 series A twenty dollar bill that happened to appear on the ground about six inches from the no parking sign, so I picked it up and put it in my left pants pocket." Evolution is more along the lines of "I found some money on the ground."

In this case, the rats probably evolved the hollow hairs for a reason (IIRC these aren't uncommon in the animal kingdom. Isn't polar bear fur the same way? A series of (hollow) tubes?), the plant evolved poison for obvious reasons, and the two working together is more a case of happy natural symbiosis than it is plain old fashioned evolution.

I'm curious if the plant chewing and bathing routines are unique to just this rat, or if they all do it.

Re:How did this evolve? (4, Interesting)

Chris Burke (6130) | more than 3 years ago | (#36979818)

Polar bear fur isn't hollow, but it is transparent, and directs sunlight down to the bear's skin like a coat of fiber optic cables, which is basically what they are.

But yeah, this isn't that unusual. Chewing and grooming are normal behaviors for rats. The hairs could have evolved for any number of reasons, and may have been quite different, maybe just specialized whiskers, before the poison plant made predator-poisoning the main selective pressure.

There's other cases of this kind of thing. For example, hummingbirds and the flowers they feed from will often undergo runaway evolution where the hummer's bill will be specialized to feed on the flower's specialized form that only the hummer's bill will fit. Even more amazing, there's a species on a Caribbean island where the males and females aren't just different in plumage, but also very different in bill shape which is unusual. Each of the two sexes feeds exclusively from two different but closely related species of flower.

The theory was that when the hummers first arrived on the island, there was only one species of flower, and the more aggressive males monopolized the flowers that had the highest nectar output while the females were stuck with the ones with lesser output. The result was that the higher output plants were cross-pollinated by the males while the lower output plants were pollinated by the females, setting the stage for the two populations of flowers to begin diverging into separate species, and for each sex of hummer to follow.

I dunno, I thought that was neat.

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36982464)

Polar bears do have hollow fur. It can occasionally have algae grow in the hollow hair and give them a pale green coloring. I used to love going to see the bears at the zoo as a kid where there legs mainly turned greenish during the summer.

Re:How did this evolve? (1)

Chris Burke (6130) | more than 3 years ago | (#36984544)

Nevermind, I guess my info was outdated and wrong.

Re:How did this evolve? (1)

shugah (881805) | more than 3 years ago | (#36980266)

This isn't exactly co-evolution because the toxin in the tree bark has evolved independently from the rat for reasons that benefit the tree - there is no co-dependence. Try co-evolution is where the dependency is mutual - such as with flowers and specific pollinators evolving together.

Re:How did this evolve? (2)

flibbidyfloo (451053) | more than 3 years ago | (#36979616)

I know that when I eat certain herbs, I sweat them out and smell strongly of that herb whereas other people I know are fine. I wouldn't be surprised if that is related, the rats that could not sweat out the chemicals died, those that could survived, the ones who sweated through barbs fared even better.

This is a common mistake made by people with a poor understanding of anatomy. Toxins in your body are excreted by your liver and intestines, not your skin.
Your sweat glands are there to regulate your temperature and are in no way designed to expel toxins.

People smell like things they've eaten because it's on their breath and on their hands.

Re:How did this evolve? (1)

Vaphell (1489021) | more than 3 years ago | (#36979778)

http://en.wikipedia.org/wiki/Garlic [wikipedia.org]
Garlic is known for causing halitosis, as well as causing sweat to have a pungent 'garlicky' smell, which is caused by allyl methyl sulfide (AMS). AMS is a gas which is absorbed into the blood during the metabolism of garlic; from the blood it travels to the lungs (and from there to the mouth, causing bad breath) and skin, where it is exuded through skin pores.

Re:How did this evolve? (1)

flibbidyfloo (451053) | more than 3 years ago | (#36979932)

http://en.wikipedia.org/wiki/Garlic [wikipedia.org]
Garlic is known for causing halitosis, as well as causing sweat to have a pungent 'garlicky' smell, which is caused by allyl methyl sulfide (AMS). AMS is a gas which is absorbed into the blood during the metabolism of garlic; from the blood it travels to the lungs (and from there to the mouth, causing bad breath) and skin, where it is exuded through skin pores.

Yes, ok, some exogenous organic compounds make their way into sweat. But garlic is not a toxin, and the gas that gets to your pores is a byproduct, not a design feature of sweat glands. Since you obviously know how to use wikipedia, try reading the one on perspiration.

Re:How did this evolve? (1)

Hognoxious (631665) | more than 3 years ago | (#36979862)

Really? I know if I eat curries/tajines with a lot of fenugreek in them the smell is strongest in my armpits.

Re:How did this evolve? (1)

ImprovOmega (744717) | more than 3 years ago | (#36979966)

OMG! Dude, that is waaaaaay TMI. I know this is slashdot, but c'mon.

Re:How did this evolve? (1)

rubycodez (864176) | more than 3 years ago | (#36982448)

Does this give you a breeding advantage?

Re:How did this evolve? (1)

Hognoxious (631665) | more than 3 years ago | (#37000994)

If I stand next to someone long enough, it gives them a disadvantage ;-)

Re:How did this evolve? (1)

rubycodez (864176) | more than 3 years ago | (#37003552)

I often eat food with all that good stuff in it, was wondering if upping the dose would have certain pheronome-like effects, even if only on women from certain parts of the world.

hmmmm, but not to smell like dinner in places where cannibalism was recently given up.....

Re:How did this evolve? (1)

improfane (855034) | more than 3 years ago | (#36980104)

No.

I can eat foods that do not taste of a herb with a knife and fork and my skin smells very strongly of the herb - even if you could not smell the herb in the food.

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36982768)

Gas chromatography [separationsnow.com] disagrees with you.

Re:How did this evolve? (1)

flibbidyfloo (451053) | more than 3 years ago | (#36993002)

I'm not sure which one of us you are saying it disagrees with, but if it's me, I'll have to disagree in turn with your reading of the linked article.

The key point I see is that while 8 compounds of the total 44 identified in sweat are associated with fenugreek consumption, none of them were determined by the olfactory experts to have a related odor.

The only GC zone characterized as having that odor was an unidentifiable substance. The researchers *merely speculated* that it might be a metabolite of the key fenugreek odorant sotolon.

So, while this it's still an unanswered question whether improfane's profane stench comes from sweating out his curry obsession, it's sort of a moot point.

I obviously wasn't clear in my original post, because my point I was trying to make is that many people think that human sweat glands are part of a detoxifying system that removes poisons from the body. It isn't, and it doesn't. This holds true for the OP's suggestion that food smells coming out in human sweat might be related to a similar mechanism in rats, which don't even sweat.

However, I will withdraw my overly broad statement about where peoples' smells come from because it is possible that some such odors might originate from one's diet. I may have been only partly right on that count.

Re:How did this evolve? (2)

flibbidyfloo (451053) | more than 3 years ago | (#36979624)

It does make you wonder how something so specific could evolve, the relationship between a poisonous plant and then the distribution mechanism.

I wouldn't be surprised if that is related, the rats that could not sweat out the chemicals died, those that could survived, the ones who sweated through barbs fared even better.

Oh, and rats do not sweat. They regulate their temperature by constricting or expanding blood vessels in their tails.

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36980614)

Fucking awesome.

This is the first new thing I learned on /. in years!

I don't know why I'm so fucking amused by this little fact. I think I worked too much.

How would say, huh

Rats don't sweat. They control their temperature with their tail. Fucking amazing.

Re:How did this evolve? (1)

AngryNick (891056) | more than 3 years ago | (#36980052)

It does make you wonder how something so specific could evolve

First of all, the rat (Lophiomys imhausi) evolved into a non-rat, with a nice, cute, fluffy tail (see exhibit A [youtube.com] . That prevented them from being killed by humans. The poison quill adaption was just to piss off dogs.

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36980150)

A bunch of rats all ate different things, the ones that liked to eat this herb poison crap survived eating it and was able to survive getting killed.

Then the next bajillion rats that came out following that rat ended up having some secrete poisons and they lived even better.

Evolution is the most insane version of trying out every methodology slowly but surely.

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36984966)

was able to survive getting killed.

I wish I could survive being killed.

Re:How did this evolve? (1)

blind biker (1066130) | more than 3 years ago | (#36981530)

If you read the fucking article, you'd know these weird rats chew the bark of the plant and then lick their fur to store the poison on it. They don't sweat the poison out.

Re:How did this evolve? (1)

improfane (855034) | more than 3 years ago | (#36983136)

If you read the article, they still don't know why they don't die when they chew the bark.

Idiot.

hedgehogs do it as well (2)

SuperBanana (662181) | more than 3 years ago | (#36981768)

My friend's hedgehog licked my hands and then started foaming at the mouth, and then spreading it on its quills. She explained:

https://encrypted.google.com/search?q=self-annoiting

If a hedgehog tastes something nasty, the froth it up and spread it on their spines. It works - if you get pricked hard, you can see a bit of an allergic reaction around the pricks (the spines are not like porcupines, ie, they don't have barbs. They're just somewhat sharp.)

How can they evolve that knowledge? Or is it aggression that is evolved too?

The same way any other trait evolves- the ones that do it survive better than the ones that don't.

Re:How did this evolve? (0)

Anonymous Coward | more than 3 years ago | (#36982410)

Ampulex Compressa. [wikipedia.org]
Evolution is amazingly intricate.

Do animals that disperse poison even know it's a defensive mechanism?

I think its largely irrelevant if they know because the ones that don't use it right die, so you generally only see the ones that know.
Its also difficult to reason about knowing of another creature without anthropomorphising too much.

Re:How did this evolve? (1)

guruevi (827432) | more than 3 years ago | (#36984492)

There is no such thing as macro-evolution. The rat doesn't all of a sudden start eating poisonous plants and sweating them out.

Most likely the selective pressure was made in several small steps:
- There is less food at one point and the only thing left is poisonous plants. Some die of the plant, some die of hunger. Those that are somewhat 'immune' to the poison get to breed.
- If there is less food for the rats, there is usually less food for the rest of the ecosystem as well. Things start eating or bringing to their kids the rats that are still alive (most animals don't eat carcasses). Some rats have groomed after eating the poisonous plants and thus are better at not being eaten thus they can breed.
- As time goes on, certain rats that bring out the poison better (sweating, length of arms for grooming, certain hair types that hold on to the poison better) have better survival rates and get to breed.

The thing is it doesn't even have to happen this way. I don't know the details about this rat but it could be that the hollow hairs evolved for an entirely different purpose. If the climate was dry, this might've been better at catching dewdrops to drink etc. etc.

Evolution is hard and the whole 'tech path' isn't always available to us (or we're simply not interested or we haven't investigated it yet) yet we can make conjectures based on the time and place of where we find a preserved ancestor specimen or DNA analysis reveals who it's cousins are in other areas.

It's a shame... (1)

NecroPuppy (222648) | more than 3 years ago | (#36979038)

That the rat isn't from Sumatra.

Re:It's a shame... (1)

Opyros (1153335) | more than 3 years ago | (#36979936)

If it were, the world would not yet be ready for the tale.

Coat (1)

thelowedown (2368436) | more than 3 years ago | (#36979064)

Where can I get a Giant African Rat coat before PETA is all over me?

Re:Coat (1)

littlegruz (2428768) | more than 3 years ago | (#36979442)

Africa I believe

Re:Coat (1)

omi5cron (1455851) | more than 3 years ago | (#36979964)

I'm thinking, if you wear the coat, they WON'T be all over you, except maybe as formerly living activistas!! (yes,that WAS activistas!!)

"hardwired into the rodent's brain" (0)

Anonymous Coward | more than 3 years ago | (#36979108)

No shit. This is how evolution works.

Why are journalists always so surprised that animals instinctively do things that gave their ancestors an evolutionary advantage (and hence are the reason why this animal's ancestors survived to procreate).

Clue bat for idiot journalists: The ones programmed to do things that get them killed before procreation don't pass on the instinctive trait.

Re:"hardwired into the rodent's brain" (0)

Anonymous Coward | more than 3 years ago | (#36979180)

The ones programmed to do things that get them killed before procreation don't pass on the instinctive trait.

Then how do you explain Americans ?

Oh, right, they evolved to breed at a younger age, beating the idiocracy clock.

next thing... (1)

Anonymous Coward | more than 3 years ago | (#36979172)

he gets a starring role in the desperate A-Team 2: What else can we do to ruin Mr. T

That's a shock (0)

Anonymous Coward | more than 3 years ago | (#36979248)

You mean my exwife came from Africa?

New Pets (1)

Forestwalker (2428752) | more than 3 years ago | (#36979254)

Could be a cool pet. Bet no one ever tries to pet it without permission.

Whoa. (1)

blair1q (305137) | more than 3 years ago | (#36979276)

Whoa.

I dated that chick.

The 80s were cool...

Pity (3, Funny)

ripdajacker (1167101) | more than 3 years ago | (#36979572)

I pity the fool who touches my mohawk!

Re:Pity (1)

funkify (749441) | more than 3 years ago | (#36996190)

Are you calling Mr. T a giant African rat?

Damn (1)

Thinine (869482) | more than 3 years ago | (#36979900)

Damn nature, you scary!

Imagine (0)

Anonymous Coward | more than 3 years ago | (#36980182)

Imagine a Beowulf cluster of those!

Denizen of the Fire Swamp? (0)

Anonymous Coward | more than 3 years ago | (#36980214)

Sounds like the ROUS.

'70s flashback (1)

circletimessquare (444983) | more than 3 years ago | (#36980334)

Ratvis Bickle: [Ratvis is admiring his crest in the mirror] Huh? Huh?
[Flexes]
Ratvis Bickle: Faster than you, fucking son of a... Saw you coming you fucking... shitheel.
[Crest Stiffens]
Ratvis Bickle: I'm standing here; you make the move. You make the move. It's your move...
[Lunges]
Ratvis Bickle: Don't try it you fuck.
[Reflexes]
Ratvis Bickle: You talkin' to me? You talkin' to me? You talkin' to me? Then who the hell else are you talking... you talking to me? Well I'm the only one here. Who the fuck do you think you're talking to? Oh yeah? OK.
[Stabs the wall with his crest]

Re:'70s flashback (0)

Anonymous Coward | more than 3 years ago | (#36984228)

You could do a movie about taxi driving zombies. That would be great.

Rat poison (1)

shugah (881805) | more than 3 years ago | (#36980422)

So would rat poison (coumadin / warfarin) still work on these rats?

Re:Rat poison (0)

Anonymous Coward | more than 3 years ago | (#36981134)

Probably. Rat poison doesn't work the same way. It has no effect on the heart. It works by interfering with coagulation of the blood, and in large enough doses you bleed into your stomach, from your gums, etc. That's why the antidote for warfarin poisoning is Vitamin K.

O'Reilly (0)

Anonymous Coward | more than 3 years ago | (#36980440)

Okay guys, what book are you gonna put this on the cover of?

Re:O'Reilly (1)

Sulphur (1548251) | more than 3 years ago | (#36980950)

Okay guys, what book are you gonna put this on the cover of?

Introduction to Ratfor?

Re:O'Reilly (1)

Alex Belits (437) | more than 3 years ago | (#36985274)

Managing Samba4.

Honey badger (0)

Anonymous Coward | more than 3 years ago | (#36981660)

Honey badger don't give a fuck.

This rat would (1)

future assassin (639396) | more than 3 years ago | (#36981686)

make quite the politician.

Re:This rat would (0)

Anonymous Coward | more than 3 years ago | (#36982990)

Don't insult rats by comparing them to filthy, rotten scum!

Newsflash: Africa sucks! (0)

Anonymous Coward | more than 3 years ago | (#36984238)

Like we needed more proof?

Chew (1)

immakiku (777365) | more than 3 years ago | (#36987272)

Summary is a bit inaccurate, leading to uninformed comments and questions on this thread. From the article,

The researchers found that the rats chew the bark of the poisonous tree and lick themselves to store their poisonous spit in specially adapted hairs.

They do not eat the plants. They chew it. This is the same way people chew certain herbs and then apply it to wounds to numb the pain. They don't eat those plants - if they did they'd be in poor health indeed.

It's an acquired Immunity! (1)

DadLeopard (1290796) | more than 3 years ago | (#36988618)

http://en.wikipedia.org/wiki/Mithridatism [wikipedia.org] It probably starts with the Mother rats milk and continues with additional doses each time it chews the bark! As for the Adaption of the Back hairs, that probably happened when the Rats that had hair better able to absorb the saliva lived longer to have more descendents than the ones that got eaten early because their hair didn't hold enough poison to deter predators!

In another study (0)

Anonymous Coward | more than 3 years ago | (#36989942)

Very similar traces of poison was discovered in the tips of Pauly-D's blowout; this however, is believed to have been evolved from very high levels of gel, hair spray, and spray tan combined for a duration of 23 years.

I dunno, I thought it was neat.

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