Given a choice between eating chocolate alone and rescuing their pals, rats will apparently save their pals and then share the chocolate with them. Trapping a rat in a cage sparks its cagemate into action, as it figures out how to open the cage and liberate its jailed friend. This is an unusual example of rats expressing empathy, a trait thought to be reserved to us higher mammals, the primates.
It's interesting from an evolutionary perspective, because it suggests that pro-social behaviors originated earlier than previously thought. And it's interesting from a neuroscience perspective, because it suggests rats are wired for pro-social behaviors, which means they can be used as a model for human behaviors.
"There are a lot of ideas in the literature showing that empathy is not unique to humans, and it has been well demonstrated in apes, but in rodents it was not very clear," said study co-author Jean Decety, a psychiatry and psychology professor at the University of Chicago. "We put together in one series of experiments evidence of helping behavior based on empathy in rodents, and that's really the first time it's been seen."
The simple experiment used no fancy technology and no bizarre new methods — it just separated two rat friends that normally shared a cage and watched what happened.
The rats started out sharing a cage for two weeks, enough time to get acquainted. Then the animals were placed in a special chamber, where one rat was inserted into a cramped restraining device that could be nudged open from the outside. The other rat was free to roam around and observe the plight of its jailed pal, both squeaking ultrasonic alarm calls all the while.
The free rat was agitated when its cagemate was trapped, which the researchers say is evidence of "emotional contagion," a lower form of empathy in which animals share in the fear or distress of another animal. But what happened next was much more like true empathy. Although the rats were agitated, they didn't freak out, freeze or become overwhelmed with fear, which is one possible reaction to emotional contagion. Instead, they coolly circled the container, bit it, clawed at it and generally spent time near it, even reaching through holes to touch (and comfort?) the trapped rat.
The researchers tried several different controls to figure out what was motivating the rats. They experimented with empty cages, to ensure the rats weren't just curious about the box-thing, and they found the rats ignored the empty ones. They tried keeping the rats separate even after liberation — socialization would be a reward for freeing the trapped rat — yet the rat still freed its friend.
They even tried a "cagemate versus chocolate paradigm," the authors explain. A free rat was placed in an area with two containers, one containing its cagemate and one containing pieces of chocolate. It would open the chocolate cage about as often as the rat cage, suggesting "the value of freeing a trapped cagemate is on par with that of accessing chocolate chips." But more than half the time, the free rats did not hog all the chocolate chips. They saved them and let their liberated cagemates have half of them.
The rats figured out several different ways to open the door, and the researchers say they clearly learned what would happen. "Whereas rats initially froze after the door fell over, later on they did not freeze, demonstrating that door-opening was the expected outcome of a deliberate, goal-directed action," they write.
Female rats were also more likely to become door-openers, "which is consistent with suggestions that females are more empathic than males," the authors added.
Inbal Ben-Ami Bartal, the paper's first author, said in a statement that the rats were not trained at all, but figured out how to complete a difficult task to help their cagemates.
"These rats are learning because they are motivated by something internal," Bartal said. "They keep trying and trying, and it eventually works."
The study is published in this week's issue of Science.
This looks more like the rats are just curious about the cage and want to see the inside. The rat on the outside immediately rushes into the cage after it opens, mostly ignoring the other rat. PopSci, I know you can do better than this.
@tyronemojojohnson You can read, right? "The researchers tried several different controls to figure out what was motivating the rats. They experimented with empty cages, to ensure the rats weren’t just curious about the box-thing, and they found the rats ignored the empty ones."
I hope PETA does not try to use these results against animal testing, they should realize that was the way we determined this.
To be honest that just does not amaze me. As far as i see it the rat was liberating his friend in, either; an attempt to breed,or reunite as a pack for survival (geese are a perfect example). When they grouped a female she had greater motivation , not because of being female with a strong sense of empathy, but because they had a greater urge to mate, and maintian survival. The scientist already claimed the two were cage mates so what is there to say that rats wont uniform in a colony and attempt to protect one another to ensure species survival. Take this same test, but with dogs, and you can see that dogs will attempt to free there caged mate, but later will try patience because they realize it is not possible, and in time their partner (so to speak) will be free. Lastly, we need actual proof. Maybe a CT scan that they have used to map the human brain and emotions. So lets not jump to conclusions and actually believe in animal emotions.
...At least not yet.
Soo... hasn't it already been proven that cats and dogs do this? I'm also pretty sure I saw something somewhere about an octupus doing this as well. This hardly seems ground breaking and/or amazing.
In fact, I'm fairly certain that if you did the same experiment with virtually ANY known social creature who is physically capable of performing the task, you would get the same results.
As far as the "Female rat's were more likely to become door openers" statement... well, again, I point to OTHER research, especially in primates, that demonstrates that in general females tend to learn "Skill" oriented tasks easier and sooner then thier male counterparts. However as the "males" got older they eventually picked up on the tasks and became equally adept. So the question then becomes, "How OLD were the rats?" and "Did they SEE other rats perform the task?" so on and so forth.
Xionanx, I think you missed the part of the article that talks about how this is the first observed instance of this behavior in rats. Yeah, they've already observed this type of behavior in higher-order mammals.
The implication is that this trait, empathy, showed up a lot earlier in mammals than they thought, making rats a better candidate for behavioral studies related to humans than previously thought.
Pretty interesting. Obviously way too many variable to make any truly accurate judgements, nevertheless a step in the right direction.
Interesting but ultimately not surprising really. They don't breed like crazy because they dislike each other, and this idea that animals are complete zombies is laughable. Be interesting to know however if certain insects can exhibit similar behaviours.
Also that is the loudest test environment on the planet, are they on a train or something? LOL
Humans are amazingly STUPID!
I don't think it was empathy. I think the rescue rat was jealous of his friend being inside the jail, so he wanted in. See how he immediately went inside the jail after opening the door? He did it every time. I think he knew that rescuing his friend is irrelevant, seeing that both of them are inside a bigger case, so he might as well do something worthwhile, like how to stop his friend from squeaking so much?
I think it is surprising that the scientists were surprised by a social animal behaving in a "socially acceptable" way.
I agree with much of which has been said. deebirs brings up a good point that these are social animals performing social behaviors. But to all who simply dismiss the idea of animals performing in empathetic ways, you should think twice. The title of the article suggest that the scientist were demonstrating that non-primate animals could carry the same empathetic feelings that primates do, not that all of a sudden these rats think like humans. Some driving force is acting here. Claiming this to be just an act of survival instinct is absolutely bogus. Would you not agree that an act of survival is completely selfish. Wouldn't the rat go and eat first? Wouldn't a mama bear flee instead of protecting her cubs? What i'm getting at is that the article suggest that more mammals than just primates can carry empathetic feelings. Maybe it's empathy, maybe it's not but something more is driving this rat to release the other. Something more than just a flight or fight, cut and dry survival instinct. Something on a more emotional level.
@gogotiff Are you blind? Does that rat look like it's sympathetic towards the other rat? As for the empty cage test, maybe the outside rat thought there was food or something in the small cage with the other rat. Don't be so narrow-minded, you sheep.
The trapped rat may have had something better than chocolate to offer ;) the way the free one runs straight in to sniff the area the trapped rat would have dribbled most urine.. was she in season perhaps?
Did they control this with same sex mice? or better yet neutered ones? I missed that bit in the article if they did..
@tyronemojojohnson You have just proved that you cannot, in fact, read. "They tried keeping the rats separate even after liberation — socialization would be a reward for freeing the trapped rat — yet the rat still freed its friend. They even tried a “cagemate versus chocolate paradigm,” the authors explain. A free rat was placed in an area with two containers, one containing its cagemate and one containing pieces of chocolate. It would open the chocolate cage about as often as the rat cage, suggesting “the value of freeing a trapped cagemate is on par with that of accessing chocolate chips.” But more than half the time, the free rats did not hog all the chocolate chips. They saved them and let their liberated cagemates have half of them."
These conclusions are not based on whether or not the test rats "look sympathetic". Talk about narrow-minded. Try reading the source material. I'm not just taking some random blog post at face value like a "sheep". I'm actually looking at the reported data and drawing my own conclusions.
I'm a neuroscience researcher by the way. This is my profession. Animal behavior happens to be my specialty. Look forward to hearing your rebuttal.
@gogotiff I'm sorry, but maybe I can't read after all. I have not seen any reported data in this article at all, other than the video showing one instance of a rat freeing another. You even said: "These conclusions are not based on... I'm actually looking at the reported data and drawing my own conclusions."
You are parroting Bartal's conclusion. Reported data my ass.
Also, a person with your ego would probably announce that you're a doctor if you were. Since you claimed to be a "neuroscience researcher," I'm assuming you do not have a Ph.D. I do congratulate you, however, for being an active member of PopSci. These articles do seem to be geared toward lab technicians.
@tyronemojojohnson Allow me help you out. You see those bolded blue words in the article? Those are called links. Click on them and they will lead you to... *GASP!* A scientific journal publication! With data! Numbers! Methods!
Holy chocolate chips, Batman! Someone give this girl a PhD! :)
@gogotiff Honestly, some people have better jobs than reading about recent experiments to try to impress post-docs. These people don't subscriptions to online scientific journals.
I do find it funny that you do not, in fact, have a PhD, yet you brag about being a researcher.
(Sorry, no sarcastic congrats included)
@tyronemojojohnson I never bragged about being a researcher. I was simply pointing out that my academic and professional career happens to be in the same exact field as the topic of this post, and therefore you could take heart that I was not just talking out of my ass when commenting on the experiments and conclusions being discussed above. And I only chose to mention this because you called me a blind, narrow-minded sheep. Just wanted to reassure you that I wasn't just your average amateur science buff trying to interpret complex animal behavior studies, so that you wouldn't prematurely write me off as someone who has no idea what they're talking about.
12/8, You question a key point in the text and put down PopSci for blogging about an experiment that you consider invalid.
12/8, I reply (maybe too harshly, I admit) by quoting where the text has already addressed your concerns.
12/14, You reply by questioning another point of the experiment, and then insult and scold me for blindly regurgitating conclusions that are not my own.
12/22, I reply by again quoting where the text directly answers your questions, defend the author's data interpretation, and then attempt to validate my own interpretation by pointing out the extra info in the reported publication and my experience in the field. See comment above.
1/11, You call out this invisible reported data, and my "ego", and start talking about graduate degrees.
1/13, I helpfully direct you to the linked publication, and wonder why I ever got involved with this thread in the first place, since it's clear you're the type of person that just comments on articles without reading them, a.k.a. an internet troll.
1/15, You reply with, if I may paraphrase, "I'm better than you. You're dumb. You suck."
Congratulations. You win. :)
@gogotiff Thank you.
Why I'm getting involved, I don't know but @tyronemojojohnson do you understand the difference between quantitative and qualitative research?
"I have not seen any reported data in this article at all, other than the video showing one instance of a rat freeing another."
So after you look up the definition of qualitative (assuming you can read it) you will come to realize that you just got your ass handed to you by @gogotiff. There is data there, in the hyperlinks (like @gogotiff pointed out you blind sheep), but that data is unnecessary to the article's chief goal because it's qualitative research not quantitative. The researchers goal was to observe the behaviors of the rats and then give a conclusion based on their observations. That is what qualitative research is.
btw if your going to criticize someone for not having a phd... at least finish your sentences troll
"These people don't subscriptions to online scientific journals. I do find it funny that you do not, in fact, have a PhD, yet you brag about being a researcher."
P.S. @gogotiff is a neuroscience researcher.... what are you? Sanitation Engineer?