Mice Run for Fun, Not Just Work, Research Shows

[alfred russel]

You typically don't see animals running laps in the wild.

There typically aren't tracks to run laps in the wild either.

[grumbler]

I'm confused why you wouldn't anticipate these results. Lots of humans run for fun, and it is hard to find many human behaviors that don't have parallels in animals. Also there appears to be clear cardiovascular benefits to running and biological processes to make it rewarding.

I am confused by what you mean when you say "it is hard to find many human behaviors that don't have parallels in animals."  Humans dress in clothing, but for decoration and for protection from the weather.  What animal dresses in clothing?  What animals employ money, or cook their food, or post on the internet?  There are a host of human activities with no animal parallels.

I wouldn't expect mice to climb into wheels in the woods and run for no gain, because it is counter-survival.  It expends energy which the critter is going to have to risk its life to regenerate.  It places the critters in the open, where their protective coloration and behaviors do them no good.  This specific behavior cannot be instinctual, because the wheel is artificial.  So, the mice must be willing to court death in order to run unimpeded by terrain or obstacles.  That surprises me, given how timid mice normally are.

[alfred russel]

I am confused by what you mean when you say "it is hard to find many human behaviors that don't have parallels in animals."  Humans dress in clothing, but for decoration and for protection from the weather.  What animal dresses in clothing?  What animals employ money, or cook their food, or post on the internet?  There are a host of human activities with no animal parallels.

Dressing in clothes has a parallel, for example hermit crabs. Primates have been shown to use various objects as mediums of exchange.

Your last two examples are concerning using technology. Of course there are many technologies that humans have that other animals do not. I don't know of any non human animals that cook food, as humans are the only species that has the technology of fire, but some take steps to prepare it by doing things such as washing. Likewise, humans are the only species that uses the internet, but the underlying activity, communication and learning, has many parallels.

I wouldn't expect mice to climb into wheels in the woods and run for no gain, because it is counter-survival.  It expends energy which the critter is going to have to risk its life to regenerate.  It places the critters in the open, where their protective coloration and behaviors do them no good.  This specific behavior cannot be instinctual, because the wheel is artificial.  So, the mice must be willing to court death in order to run unimpeded by terrain or obstacles.  That surprises me, given how timid mice normally are.

It is counter to one aspect of survival. Another aspect of survival is that many mammals seem to have designs that require a good bit of physical activity to be in top condition. Running is a good example of an activity that has both a cost (energy) and a payoff (better health). Running without a wheel generally means you have to cover a bunch of territory--which exposes you to predators. A wheel keeps you contained in one place.

[dps]

My thought was that we already knew that hamsters runs for fun.  Since mice and hamsters are both rodents (and in the same family IIRC), I figured it highly likely that mice would also do so, and would have been quite surprised to learn otherwise.

[Josquius]

Bit gerbils don't like wheels

[dps]

Bit gerbils don't like wheels

I wouldn't know, I've never bit a gerbil.

[CountDeMoney]

You know, they make little irradiators specifically for rodents.  They're like little microwaves with no windows.  30 seconds and they're done.

[grumbler]

My thought was that we already knew that hamsters runs for fun.  Since mice and hamsters are both rodents (and in the same family IIRC), I figured it highly likely that mice would also do so, and would have been quite surprised to learn otherwise.

I always thought hamsters ran in the wheel because they had no other choice.  I'm surprised that the mice prefer the wheel to just running around on their own, not that mice run around a lot.