The urge to go for a spin has deep genetic roots (so it seems)

I was very surprised to hear from my son yesterday that he went on (what to me is) the most terrifying looking carnival ride at the Brisbane Ekka.  This one:

As you can probably tell, it spins around the central axis while the ends also spin.  Nauseating.

He did survive, but said he'll never go on it again.  

I'm pretty chicken when it comes to fast rides, and am not a fan of the falling sensation.   But by a coincidence, this week's Science magazine has a charming story about how the urge to voluntarily engage in unusual, repetitive motion goes back a long way down the chain of evolution:

Nearly everyone has fun on a carousel—including, possibly, fruit flies. Scientists observed some flies embarking on a spinning platform voluntarily and repeatedly, suggesting the animals may find the movement appealing for some reason, according to a study posted on the bioRxiv preprint server earlier this month.

“The flies are fulfilling all the criteria of play as we understand it in other animals,” says Samadi Galpayage, a behavioral scientist at Queen Mary University of London who discovered  bumble bees play with objects and who was not involved in the work. “There isn't really an alternative explanation so far. Whether that’s [evidence of] fun in itself—that’s the next question.”

Sergio Pellis, a behavioral scientist at the University of Lethbridge, says he finds the study—which has yet to be peer reviewed—“very exciting.” If confirmed, he notes, it would add to the small but growing pile of evidence for play in invertebrates—and would be the first instance of a type called “locomotor play” in these animals. Locomotor play involves the movement of one’s own body, such as running, jumping, or swinging. It’s different from object play, as bees have been observed doing, or social play, which has been observed in certain wasps and spiders.

The idea behind the study was inspired, ultimately, by a duck. Years before co-author Wolf Hütteroth became a neurobiologist, he remembers one day seeing a lone duck floating down a fast-moving river. Just as the animal was nearly out of sight, it flew back upriver, alit on the water, and floated back down—over and over again. “I never stopped wondering what motivated the duck to perform such curious behavior,” he says.

In February 2016, Hütteroth attended a symposium where researchers were discussing whether insects can act with intention. He pondered how to test whether flies would do something similar to the rapids-running duck.

He and Tilman Triphan, a colleague then at the University of Konstanz, decided to build a carousel of sorts. They’d offer male laboratory fruit flies (Drosophila melanogaster) the chance to hop onto a spinning section of floor in a stress-free, if otherwise unexciting, environment. He didn’t think the flies would actually go for it. “My expectations were extremely low,” he says. Some of the flies ignored the contraption. But a small group of them acted as if they’d just discovered Disneyland. 

Triphan and Hütteroth—who have both since moved to the University of Leipzig—report in their preprint that a subset of the flies spent 5% or more of their time on the turning wheel. When the researchers put two disks in the arena that alternated spinning every 5 minutes, some flies spent their time bouncing back and forth between whichever carousel was spinning.

Towards the end of the story, there's another "play" behaviour that I didn't need to know about:

Pellis notes there has been resistance to the idea that animals outside of mammals engage in play. He recalls research in the 1970s on roughhousing in cockroaches, for example, that would immediately be considered an example of play if puppies were doing it.

Maybe Mortein suppressed publicity about that research, because I sure don't remember it...