Animals in the wild found to use running wheel if given the choice | Hacker News Reader

Animals in the wild found to use running wheel if given the choice

phys.org

184 pointspwg115 comments

Hi there,

If you liked this article perhaps you'll be interested in a project I've been working on. My wife has a Hedgehog (yeah, like Sonic) and he's pretty shy. He also has a wheel and runs ALL night.

To feel that he interacts a little more I connected a wireless node with a magnetic switch so I could count how many laps he runs every night, and therefore the equivalent distance. Every morning he tweets how much he ran, just like RunKeeper :)

Check out his twitter account here: https://twitter.com/runhedgie

And, of course, the code is hosted on github: https://github.com/jlhonora/iot

I just finished this project yesterday, but I have many more ideas to add. I'd like to correlate running activity with temperature (hedgies are pretty sensitive to cold weather) and ambient light. I'd also like to make a public API so that anyone can analyze his activity patterns.

So, stay tuned and follow!

... now I feel terrible at slacking off at my jogging. Little guy is like 4 inches tall and running 5.8km last night.

Well, there's a catch with all of this. The wheel has some inertia, so running in it should be easier than running the same distance on the floor. The ran distance is still the same , regardless of this fact.

And I'm trying to keep up with my jogging as well :)

A body also has inertia that makes it easier to keep running. The wheel may have more, but that also means that it takes more effort to bring it up to speed.

Also, one should take air resistance (of the running body or the spinning wheel) into account.

In physics it's generally safe to assume that all the different air resistances and drags and so on cancel out. You just draw a force diagram and everything always cancels, otherwise the hedgehog would have constant acceleration which we know isn't true.

Boundary drag on the wheel as it spins causes a loss of angular momentum, and so it slows over time unless force is applied (via adorable hedgehog legs) to keep it constant. Additionally, there are likely normal frictional forces at the meeting of the wheel and the supports, as I highly doubt they gave the pet a wheel with magnetic bearings in a vacuum.

And yes, the hedgehog must exert constant force in order to overcome this viscous friction.

On a related note, this viscous damping term scales as velocity, so the faster the wheel turns the harder the little thing has to work to keep it at a constant velocity.

In high school homework physics, it is.

This is easily a business. Easily.

Also, how about hooking up a dynamo and trickle charging devices?

Yeah, I think so too. At least a Kickstarter project. You could sell an integrated wheel with this tweeting device.

I'm already a startup founder at http://satelinx.com and http://beetrack.in , apart from teaching Computer Architecture. I do have experience making and selling hardware, what I don't have is free time :)

I'm preparing a more technical description about the system (I designed and built the hardware myself), I should post it on the feed over the weekend.

As for the dynamo, definitely! But I'd rather let the hedgehog run as smoothly as possible.

> As for the dynamo, definitely! But I'd rather let the hedgehog run as smoothly as possible.

It wouldn't take much of a dynamo to provide enough power to trickle-charge a tiny battery for a microcontroller that can connect to wifi.

Also, if you're setting up a kickstarter, don't underestimate the marketing power of powering electronics off of a hamster wheel.

You are now the only twitter account I'm following. That's awesome.

Could make videos, they could be automatic montages of different parts of his run.

Definitely. I'm saving for an infrared raspberry pi camera: http://www.raspberrypi.org/tag/pi-noir/

I like what you are doing. Where are you from and how can I help you get one of these(it's very cheap, I am happy to buy a cool gadget for someone who does cool stuff). If you'd like, then send me an email to my nick at gmail.

Nice! I never quite finished my identical project 3 years back: see https://github.com/anthonydanza/whatsuphedgehog

At first it seemed like it would be posted automatically. But you read and interpret the data for your little friend, right?

It is totally automatic. I'm still working out the tweeting time, so some variability should be expected.

The phrases are random, check the code for them here: https://github.com/jlhonora/iot/blob/master/rpi/twitter_mana... . The "mood" for the phrases depends on the ran distance.

The graph I posted was generated with matplotlip and I tweeted it manually. When I finish struggling with D3 I'll put an on-demand graph with the data.

over 14km a day for such a small creature? That's insane.

I thought just the same. At first I thought there was an error with the counting, but there's a debounce of 0.2s for every pulse https://github.com/jlhonora/iot/blob/master/arduino/IoT/pir..... The wheel is not perfectly symmetric, and I'm placing the magnet on the opposite side of the reed switch used to count each lap, so that there's no risk of getting the switch stuck generating lots of pulses.

The activity graph (shown on the twitter feed) is for that same night, which seems to be quite consistent over time. There are no peaks either, so I think it should be accurate. After all, he does run all night.

Apparently it's pretty natural for these small animals to run such long distances. My wife has a hamster and they are known to run at least 9km a night. We had to find it a different room to live in because it will be up ALL night running, and running, and running.

A) this is really cool and B) your Antu the Hedgehog has shamed me into running again.

The units used on Twitter seem a bit odd, what are mts? I'm guessing kms is KM? Would that make mts meters?

>The researchers claim the animals ran on the wheels because they enjoyed it, which could be a little bit of anthropomorphizing, as no one has been able to prove that animals other than humans experience emotions.

Is this really the state of the art? I thought the entire animal rights movement is rooted in the idea that animals can experience emotion

This is pretty great research, seeing a slug in a running wheel is particularly silly

There's proof and proof. No one has managed to prove other humans experience emotions, or even exist. Given a hypothetical model of a continually manipulated memory and consciousness you could even argue that you can't prove that you yourself have emotions (you might merely have the mistaken belief that you experience them).

To take a more pragmatic approach to proof (good enough but not absolute) Humans and some animals experience emotions. At the very least most Mammals. Probably not all animals. A trickier proposition would be whether all vertebrates do, that's a different level of debate entirely.

If you can't take things like the Monkey fairness tests as a sign of emotions https://www.youtube.com/watch?v=meiU6TxysCg&feature=player_d...

then you have a standard of proof that a lot of humans wouldn't meet.

I'd highly recommend the Blackfish documentary about killer whales regarding mammal emotions (trailer: http://www.youtube.com/watch?v=8OEjYquyjcg).

Especially this part where a mother is separated from its baby, http://www.youtube.com/watch?v=eWFo6kf21Hw ; it gives pretty good insight about whether animals can experience emotions.

Yep, I absolutely agree. Even if mammal emotions have not been scientifically "proven", I think there's a lot of strong evidence that they do experience most or all basic emotions.

It's not like it's very shocking that they would, either, considering humans aren't that distantly related from them.

As someone who has two cats, and has had a dog and a cat previously, I'm always amazed when I come across people who categorically state that animals don't have emotions. Spend a small amount of time with a cat or a dog, and it becomes pretty clear that they have moods and emotional states, albeit simpler ones that humans. I realise that domestication will have changed animals and their environmental responses, but I find it very hard to believe that dogs or cats would have developed emotions from scratch in the ~10,000 years since they were domesticated.

In my experience, those who claim animals don't have emotions are usually justifying some kind of behaviour; in one case, it was a hunter, and another, someone who was generally unpleasant and cruel to animals. The former was otherwise a nice guy, though I found his hobby extremely distasteful; the latter was an irredeemable arsehole.

> In my experience, those who claim animals don't have emotions are usually justifying some kind of behaviour

I agree. Similar things were said historically to justify slavery.

This poses an interesting ethical question.

If a subject is not known to have emotions or not. Should the party that would be inflicting emotional pain on the subject have the burden of proof (that the subject does not in fact have emotions)? Or the party that would not inflict it?

If there's a plausible chance of the entity being able to experience emotion, then the burden of proof needs to be on the inflicter. "Plausible" because inanimate objects like rocks obviously cannot ever have emotions.

Things get a little more complicated with plants, such as trees and flowers, but even there I would say it's pretty implausible that they experience emotion.

Spend a small amount of time with a cat or a dog, and it becomes pretty clear that they have moods and emotional states

Completely agree. Anecdotal I know, but I've experienced a few cases that make me certain that cats (and therefore other animals) do, indeed, have moods and emotions.

The first time I was away from my cat for more than a day (I was away for three), she sat in my front window the entire time and wouldn't leave. I had a friend feed her and she barely left to eat, wouldn't play or otherwise interact. When I got home, she saw me through the window and started meowing and pawing at the window. When I came in the door, she flopped on her back on the ground in front of me and started purring.

A friend of mine has a cat that she had to bottle feed. He (the cat) is now ultra-protective of her and gets extremely jealous when she pets her other cats - occasionally going so far as to attack the other cats for it, or not letting her pet him afterwards.

That's only two of many examples. The stories that I've heard from dog-owner friends make a good case for dogs having emotions and moods too.

We have a cat like that. He was taken from his mother too young, so over attached some. He gets upset if my wife pets any of our cats in front of him, and will sit approximately six feet away, facing away, and ignoring us if we call him over (generally you just have to look his direction). His ears twitch, so you know he heard you, he's just too stubborn to give in.

I live with two cats, and try pretty hard to keep them happy. However (even though I don't feel I'm a terrible person... ;) ) I don't think that the two cats I live with are people. I think you can make a distinction between "cats have emotions" and "cats are people who have emotions", and I think that the latter is what people must mean by "cats don't have emotions".

I don't quite get what you are implying here. "cats are people" is a patently bogus claim whereas their possession of emotion is hardly worth debating.

> "cats are people" is a patently bogus claim

There's a pervasive idea or feeling in a lot of people, I think, that animals are not just machinery, but actually very limited people, akin to mentally disabled humans, and should be treated as such (animal rights protesters, at least some vegetarians, etc). I don't think that this is patently bogus, but I do think it's not very likely.

I think when people start talking about animals feeling pain and having emotions, they don't mean that those animals have the sensory and neural hardware which produces and consumes pain signals and emotions (which is "hardly worth debating"), but that there is someone experiencing that pain or those emotions. If that's not what they mean, then the mere fact of pain or emotions wouldn't carry any impact higher than rerunning a horror film.

The whale is also pretty good. It's a documentary about a killer whale that was stuck in an inlet in Canada for years. It does a job at pulling strings, but it sold me on the animals have emotions bit. http://www.thewhalemovie.com/

This realy impressed me: Koko the Gorilla watching a sad movie https://www.youtube.com/watch?v=EWxCM6llL60

Pug watches Homeward Bound https://www.youtube.com/watch?v=Cnstd0ASQHg

Human are animals too in the end. We are just a bit more evolved than the other animals, emotion wise. So, I think emotions just evolve with the species. Maybe the mice are starting to get emotions for liking running in a wheel. The slug is just coincidence I would say.

Russell Stannard can explain it very nicely: http://fixyt.com/watch?v=IF54xqYhIGA

>We are just a bit more evolved than the other animals, emotion wise

his point is that we don't have a scientific way to measure emotions.

In my opinion if we have emotions we should demonstrate that other animals don't not the opposite.

Why do you assume that we are more evolved? The only evidence we have is that we are better at building and using tools. "More evolved" can be defined in a lot of different ways (why are we more evolved than a wasp?) I think the idea that humans are more evolved it's just a anthropocentric assumptions.

I actually made a similar argument in a graduate psychology class at an ivy league as things got a bit heated over whether animals could suffer. I might have said something like, "If you get hit in the face in such a way you can't use words, how can I know you're actually suffering?"

When working in labs studying brain function, the oddest thing I found was the huge resistance in what or what not an animal can do. Even in the face of years of research by big and small names, even with video, even when you train an animal and show them. They couldn't even provide a good hypothesis on why it was not so. It was argued circularly like trying to talk a paranoid schizophrenic out of their false world-view. Very frustrating. I would usually just tell them that if they could find a reason it wasn't so, they could easily get a nature paper out of it.

Could you provide an example? I'm having trouble understanding what you mean.

It could be as simple as a mouse being able to discriminate white from black or low tones from high tones. Sometimes I think the culture in some areas of science has become twisted. It really has to be experienced to be believed.

Ah, are you saying that scientists had trouble accepting the idea that a mouse could discriminate white from black? It seems like a repeatable test would be pretty convincing evidence. What justification was there for ignoring it?

> I thought the entire animal rights movement is rooted in the idea that animals can experience emotion

I thought it was rooted in people's knee-jerk anthropomorphic emotions, science be damned...

(Not saying they're right or wrong; they may well be right - but pretty much everyone I know who is involved in that movement does so for un-scientific reasons)

Everyone I know, who has a conviction that other humans experience emotion, believes it for unscientific reasons.

What science do you suggest they are ignoring?

I wouldn't call it "knee-jerk". It's not a reaction to a new thing. It is the new thing. Animals not having rights has been the norm for a long time.

> What science do you suggest they are ignoring?

All of it - again not saying they're wrong, just that the overall mindset I've seen is "I believe animals have emotions, and that's what matters" or "we don't need proof, it's just obvious", not "I have collected evidence beyond anecdotes that animals have emotions". By knee-jerk, I mean people tend to believe first, and look at the evidence either later or never.

(Though to be fair, much of the animal-non-rights movement seems to be similarly non-scientific :P)

Have you had a look at The Cambridge Declaration on Consciousness?

We declare the following: “The absence of a neocortex does not appear to preclude an organism from experiencing affective states. Convergent evidence indicates that non-human animals have the neuroanatomical, neurochemical, and neurophysiological substrates of conscious states along with the capacity to exhibit intentional behaviors. Consequently, the weight of evidence indicates that humans are not unique in possessing the neurological substrates that generate consciousness. Non- human animals, including all mammals and birds, and many other creatures, including octopuses, also possess these neurological substrates.”

http://fcmconference.org/img/CambridgeDeclarationOnConscious...

Perhaps (I think you could say similar things about the average supporter of any mainstream issue.) I support animal rights, but evidence came out that they don't feel, I would find that extremely comforting.

> (Though to be fair, much of the animal-non-rights movement seems to be similarly non-scientific :P)

Much of the "animal non-rights" movement is anti-free speech (e.g. ag-gag laws) (and is the recipient of lots of government hand-out money, tries to convince that government that peaceful protesters should be classified as 'terrorists' for pushing an agenda that is detrimental to their business, etc), so they should be opposed by more than just the animal rights people.

Animal rights seem like a predominantly ethical issue to me that has little to do with science.

It's an ethical issue because it's likely that they have emotions. For instance, there is not a widespread movement for the ethical treatment of rocks. If science moved that likelihood close to certainty, the animal movements would gain lots of traction, which is what might be happening already

Insects are animals.

Jellyfish are animals.

I don't think they can feel the great range of emotions mammals can.

In fact they totally lack a brain limbic system, and it is presumed they can't.

Yes, this means that I believe it is unethical to torture a dolphin or a dog, but I don't give a damn for mosquitoes or flies.

I don't know how credible this is, but scientists have apparently declared that some non-human animals have consciousness: http://fcmconference.org/img/CambridgeDeclarationOnConscious...

>The absence of a neocortex does not appear to preclude an organism from experiencing affective states. Convergent evidence indicates that non-human animals have the neuroanatomical, neurochemical, and neurophysiological substrates of conscious states along with the capacity to exhibit intentional behaviors. Consequently, the weight of evidence indicates that humans are not unique in possessing the neurological substrates that generate consciousness. Non-human animals, including all mammals and birds, and many other creatures, including octopuses, also possess these neurological substrates.

I think that the criticism that it is wrong to read emotional responses in animal behavior runs somewhat counter to evolution as it assumes that our emotional responses have not developed from our mammalian ancestry, but have rather sprung fully formed from somewhere. I tend to see the concept of anthropomorphism as something of a Abrahamic position, as it only makes sense if you already think of humans as being separate from animals and nature in general.

The "Abrahamic position" comment was interesting, although I'm not certain I understand what you meant.

I do know that while the nomadic culture of Abraham's time used animals for sacrifice and the necessities of life, the Torah explicitly states that animals have souls[1]. The Bible goes on to say animals have an affinity to God[2] and will go to heaven[3].

[1] Gen 1-20-21, 24, 30 (translation from Hebrew word nephesh)

[2] Ps 148:7-10, 150:6

[3] Isa 65:25, Rev 5:13-14

What I was getting at is that in the Abrahamic tradition, while animals may sometimes be considered to have a form of soul, they are still kept very distinct from humans, who are considered made in gods own image. In some other cultures, such as Hinduism, although the form that a soul inhabits affects it, the soul itself can move from animal to human and back again over cycles of reincarnation, so there may be less resistance in those cultures to the idea that humans are part of a continuum rather than being a separate class of entity.

But here's what people say about "dominion" in the bible.

http://hermeneutics.stackexchange.com/questions/2860/what-do...

In Psalms 145:8-21, God is described as exercising dominion over creation with compassion and loving kindness.

As an aside, I think dominion also refers to harnessing and utilizing natural resources in an economic sense. In Genesis chapter one, God mentions the word 'good' seven times, each time in reference to His creation.

The eighth time the word good is used is for gold[1], the eternal symbol of commerce.

[1] Gen 2:12

> This is pretty great research, seeing a slug in a running wheel is particularly silly

I think having some (seemingly) humourous bits in research is a great way to make it presentable to the public. Personally I found if very funny.

Sometimes yes. Other times the silly bit becomes the headline and the rest is ignored.

ah yes, good point.

  > > The researchers claim the animals ran on the wheels because they enjoyed
  > > it, which could be a little bit of anthropomorphizing, as no one has been
  > > able to prove that animals other than humans experience emotions.
  > Is this really the state of the art? I thought the entire animal rights
  > movement is rooted in the idea that animals can experience emotion

Indeed. That statement surprised me too, since I remember reading a number of sources stating that research pretty much confirms that some animals do experience emotions. So I headed over to wikipedia[1] and saw that although some (most?) research does lean towards confirming this, the scientific community is not convinced, yet. Interesting stuff.

[1] http://en.wikipedia.org/wiki/Emotion_in_animals

The "scientific community" doesn't have a unified view on animal emotion, or on any matter.

However, it is widely understood that animals are non-human persons who are aware of their own existence and who feel a wide range of emotions, just like we do. Mice feel empathy[1], elephants grieve[2], birds hold funerals for their dead[3] and so on[4].

But yes, for many scientists the overwhelming evidence that animals are sentient beings[5] with feelings akin to ours is an inconvenient truth, since nearly 20 million animals are killed each year during experimentation in the U.S. alone[6].

[1]http://www.cosmosmagazine.com/news/researchers-say-mice-feel...

[2] http://www.tor.com/blogs/2013/06/when-doves-cry-scientific-a...

[3] http://news.discovery.com/animals/birds-hold-avian-funerals-...

[4] http://www.psychologytoday.com/blog/animal-emotions/201112/e...

[5] http://www.psychologytoday.com/blog/animal-emotions/201306/u...

[6] http://www.statisticbrain.com/animal-testing-statistics/

Some of the experiments historically done (and that continue to be done) on animals are horrific. If animals do indeed suffer as humans do, just think of the massive suffering that must have been caused in the learned helplessness experiments[1], or countless unanesthetized vivisections[2], and the likely millions of animals at this point that have been purposefully infected with terrible diseases to gain insight into treating humans.

Strong evidence does not even matter, when acknowledging the facts and their implications means we have to accept our responsibility and culpability for the terrible crimes we have committed against fellow sentient beings.

[1]http://en.wikipedia.org/wiki/Learned_helplessness

[2]http://en.wikipedia.org/wiki/Vivisection

I would not use the animal rights movement as an example of scientific rigour. :)

My wife is a biologist working in animal behaviour. Among her peers, it is widely accepted that animals have emotions. Proving it in a scientifically rigourous manner, however, is extremely difficult.

> is rooted in the idea that animals can experience emotion

Is this really still a question? Isn't it common sense that many animals do have emotions? If you call emotion a state of mind, controlled by a flood of certain hormones/neurotransmitters into the brain, then even the most simple animals will have at least fear emotion. I'm pretty sure most developed animals like elephants, orcas, etc., have pretty complex emotions that are not too far from humans.

Sometimes it seems obvious they do. Other times you think they seem to be having an experience, but it's not really comparable to human emotions. And several times per day you doubt the presence of higher brain functions in the people around you.

Why should the 'emotions' animals can or can not experience have to be like 'human emotions' though? Maybe the dog can be 'sad' in a way that isn't exactly like sadness as experienced by humans, but it's still an emotion, right?

It doesn't matter how it seems though. Fact is they have.

What many are not aware of, is that when they mean "animals have emotions", they actually mean "animals have exact same emotions as human", which is false. But saying that animals don't have emotions is the same as saying that dogs are blind just because they can't differentiate some colors humans can.

> as no one has been able to prove that animals other than humans experience emotions.

Anyone who has ever had a dog who happens to be afraid of thunderstorms will tell you that dogs can very genuinely experience fear.

Fear is an emotion (http://dictionary.reference.com/browse/fear).

Well that's humans for you. Until proven otherwise, a species lacks intelligence, emotions and self-awareness.

It was not long time ago we'd claim that for our peers, based on silly traits like skin color.

By the way, I wonder where's the "proof" that humans experience emotions. I demand someone prove it to me.

We can't prove that other humans experience emotions; each individual only knows what he or she experiences. It's possible that everyone else is a sophisticated simulation.

It's possible that everyone else is a sophisticated simulation.

I'm not. I'm just the output of /dev/random on a server in Iceland, converted directly into ascii by a line of perl. It is pure chance that anything I post is coming out as understandable words. vyfQUct 18x9t ngm3H60gODwOG2OpRSeSp5 7cMG3fF9

Then why do we expect to prove such traits for animals?

Keep in mind we use said "proofs" to justify how we treat animals used for food, experiments, hunting them for sport, and so on.

Direct links to videos:

https://www.youtube.com/watch?v=T5gI1joaCxI

https://www.youtube.com/watch?v=VNaZvGZubvw

https://www.youtube.com/watch?v=5KnbD1dmJzk

Not sure why the video were wrapped in another player.

I loved the slug video. In my mind the slug is making broom brroom noises as it 'speeds' along the wheel.

Someone should put cubicles out in the woods and test whether random humans that come along decide to sit at them for fun.

Egads. I tried to read the article. I really did. But it brought my chrome to its knees. Ran a quick javascript profile, and the minified function wa() was taking using 94.16%. Inspecting it, there's a for(;;){} loop that never hits a break condition.

This only makes me hate phys.org even more than I used to.

I use Ghostery, and I got a message: "It appears that you are currently using Ad Blocking software. What are the consequences? Click here to learn more."

But at least the page loaded.

If any phys.org admins are reading this: I don't mind seeing your ads; I do object to their tracking me.

As usual, phys.org is not exactly the best source for this. (I can't think of any occasion when phys.org has been the best source for anything.)

A more informative informal summary of the research can be found at the GrrlScientist blog http://www.theguardian.com/science/grrlscientist/2014/may/21....

For those who don't mind the much drier writing style, the full text of the original scholarly article is at http://rspb.royalsocietypublishing.org/content/281/1786/2014... (it's quite short) and the "Data supplement" link at the right will get you the three videos of animals running on the wheel.

HN submitters: When you see something cool on phys.org, before submitting it ask yourself "Can I find a better source than this for the same story?". Take two minutes -- google the title of the paper, the author's names, etc. I claim that at least 75% of the time you'll easily find something that's either substantially better or textually more or less identical but closer to the original source. Then submit that instead.

The phys.org article includes the link to the original paper.

How is the GrrlScientist blog better than the phys.org article? Based on a quick scan, it seems more or less equivalent to me in terms of basic journalism standards. It just looks like a different style and perspective.

What, specifically, is problematic about phys.org?

Yes, the phys.org article includes a link to the original paper. (Did I say or imply otherwise? If so, I screwed up and I apologize. I didn't mean to.)

The GrrlScientist blog entry is better in (for instance) the following ways. It gives more context (e.g., Lorenz's earlier observation about formerly-captive animals running on wheels). It gives more information about the frequency of wheel-running by different kinds of animal. It is more accurate on at least one important point (article and GrrlScientist say 200k animal visits recorded of which 12k used the wheel; phys.org says 200k instances of animals using the wheel). It mentions, where phys.org doesn't, a very important finding: wheel-running continued even after the experimenters stopped putting food near the wheel, so it wasn't just that animals run on the wheel because they've found food there and think getting into the wheel will somehow provide more. It describes the article's comparison to wheel running in lab mice.

On the other hand, it's also more chattily verbose, which might be a good thing or a bad according to taste.

What's problematic about phys.org is that it's scarcely ever the best source for anything. Much of its content is recycled press releases, exactly the same as you can get from (usually) the website of the institution where the work was done but often with some illustrations removed and extra advertising added. Sometimes (as here) phys.org does actually write its own material, but (as here) it's usually more superficial and less informative than one can get from elsewhere.

There may be cases in which the phys.org writeup is (1) not just recycled from someone else and (2) the best available account of the matter for some plausible audience. If so, I just happen never to have encountered any.

[EDITED to add: I am not alone in thinking HN would be better linking to better sources than phys.org's blogspam. See, e.g., this lengthy collation: https://news.ycombinator.com/item?id=4676259. Full disclosure: some of the critical comments listed there are also mine.]

Well, when you encounter a running wheel for adults along your way, you would try it too: http://www.notempire.com/images/uploads/grasswheel.jpg

... which doesn't suggest that you would enjoy being imprisoned for life in a tiny cell where there is a, running wheel, bed, food and nothing else.

Certainly. That would be a different study though. The hypothesis that this study investigated is:

> If wheel running is indeed caused by captive housing, wild mice are not expected to use a running wheel in nature. This however, to our knowledge, has never been tested. Here, we show that when running wheels are placed in nature, they are frequently used by wild mice, also when no extrinsic reward is provided. Bout lengths of running wheel behaviour in the wild match those for captive mice. This finding falsifies one criterion for stereotypic behaviour, and suggests that running wheel activity is an elective behaviour.

The frog video made me laugh. It's a great experiment and this is something really new about wild animal behavior.

Consider the normal use of running for an animal: running for prey, running to not be prey... Yet, we know as humans that running can be enjoyable. For an animal, running is more often associated with hunger and fear of being eaten. I propose the running wheel presents to the animals a rare "place to run safely". Normally, running transports an animal into new, potentially unsafe locations. This running wheel was both in an enclosure, and the wheel itself offers protection from attack. I wager that 18 minute run was a mouse experiencing the joy of running without fear for the first time, and was exhilarated.

You presuppose the wild animal can understand a running wheel, something it never encountered before.

The mice, on seeing something novel, did what that normally do and try to climb all over it looking for food. They then got stuck running on it, not realizing they were getting nowhere.

It is my understanding that rodents run a lot while foraging. I've heard, for example, that wild hamsters run 4-10 miles at night while foraging.

If they put a human-sized one of these around my residence, I'd run in it.

I have one nearby, and it's great! (I can't do more than a few seconds without falling over though)

I always thought those things were impossible to run in because the rotational inertia of the wheel is way higher than the inertia of one running in it. That requires you to run at almost constant speed (if your foot stays a bit longer on the ground, you do not decelerate the wheel much, but your feet ends up a few centimeters backwards. Repeat for two or three steps, and you lose your balance).

That changed when I saw the Ukrainian entry for this year's Eurovision contest (http://www.youtube.com/watch?v=h5DhH0jWyfk). On the other hand, that wheel is smaller and likely has way less rotational inertia than the ones one finds in the typical playground, and probably also has less rolling resistance. That guy must have trained, if only to make it look effortless, but it may be easier than one would think it is.

I would imagine that the sudden appearance of food and new environment elements would set the mind of any animal in a "run around and explore" mode, especially for species living near humans.

The wheel was there for 3 years.

And one of them ran for up to 18 minutes.

2 wheels, used by 200,000 animals, which has got to be a typo, cuz thats on average 137 animals per hour.

2 wheels, 3 years, 200,000 animals is an average of 3.8 per hour.

200,000 triggers of the animal sensors, 12,000 times that the wheel started spinning.

Also: the researchers hypnotize that the slugs ended up in the wheel by accident. Some mice returned multiple times; that's a fairly good indicator that they found some benefit from it (need not be that they liked it; it's fairly easy to make up perfect direct benefits. For example, it might be that fleas jump of a mouse if it runs in a wheel for a while.

2 wheels => 100000 animals/wheel 1000 days => 100 animals/wheel*day

Do animals in cages run only after being fed? Do animals run around after being fed in general?

Based of my experience of gerbils and hamsters, there doesn't seem to be a link between feeding and playing activity, but they were always well-fed so that probably doesn't reflect anything like a state o nature.

My two cats are definitely more active when they've not recently eaten. When their food bowls are empty, they run around and play much more --- `hunger' tends to stimulate activity in them. Once they're fed, especially with something they really like and will gorge on, they tend to lie around and sleep after eating.

My understanding is that cats do this because the relatively short length of their digestive tract requires them to lie dormant for a long period to digest their food.

The article seems overly political in trying to refute the claim that laboratory animals run on wheels because they are driven insane by their environment. However ultimately they are undermining their position because it begs the question, "If animals like to have fun, should we really be doing experiments on them?". This is probably a lot easier to grasp by the general public than the more nebulous concept of whether animals experience emotions.

> the more nebulous concept of whether animals experience emotions

Is there debate about that? I suppose I took it as a given, hence all the efforts people go through to treat lab animals humanely.

I agree this debate is already over. However I think this simplifies the issue enormously and makes it a lot more likely that general public opinion can be mustered against animal testing. If you tell the tell the future adults of this world that animals like to play and have fun then ask them whether it is right that animals are experimented on then the answer, for good or for ill, is going to be a resounding no.

I see opportunities for new ways to generate electricity :)

"My Tesla is using environment friendly electricity. It is slug powered"

And it only takes 16.3 years to recharge!

I wonder if the same free animal would enjoy it for a long time or if it is merely the excitement of something new.

Thanks to this research I feel slightly less weird for preferring to run on a treadmill.

Now we need to make giant wheels for dogs!

Well I can see why, as the research states at the end animals enjoyed it.

If we see it in a scale, it's like for us humans going on a roller coaster!

Still, the experiments should put to rest the argument about whether mice in the lab are running on wheels because they live in cages—they'll do it anywhere they find one

and

They also put the wheel inside an enclosure with a small entranceway to keep large animals from knocking the wheel on its side

They mean because they are trapped in the cage and can't run anywhere else. Not that it's just in an enclosed area.

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