How does a reindeer get enough sleep? A tale of four chambers in the stomach of a herded Sámi
Furrer looked at the brain waves of the reindeer as they ruminated, and sure enough, they resembled those of deep, non-REM sleep. The less deep sleep the reindeer required, the more ruminated they were.
Santa and his reindeer deliver gifts on Christmas Eve when the king of all-nighters is pulled. But what about the rest of the year? How do real reindeer manage to get enough sleep?
She theorizes that it is a response to the environment of lush, grassy summers and snowy winters in the north. To get enough time in the summer for constant food feeding, to fatten up for the winter with very little food availability, is a strategy.
Like a cow, a reindeer has four separate chambers in its stomach and it uses the first to store grass for later use and chewing.
As scientists look to what’s next, these new findings also echo the traditional wisdom of the Sámi, Indigenous people of Norway who have herded reindeer for centuries.
Menno Gerkema, a retired chronobiologist who was not involved in the research, found the study fascinating. “I’m rather enthusiastic about all the suggestions that are hidden in this paper,” he says. Suggestions for further research to look at other animals.
Sleep and chewing with Reindeer in the Arctic (with an appendix by Mel Gibson Furrer at the University of Switzerland)
“While they chew,” Furrer says, “they are in a body position that is very similar to the one of deep sleep. They are usually quite still, though they usually have their eyes closed.
“We recorded our data without the need to use tools that would cause brain damage,” says Melanie Furrer, a neuroscience professor at the University of Switzerland.
They’re active in the summer because of the short growing season. They are lazy in the winter when there isn’t any food.
Reindeer are unusual in that their habitat is different from most other places on the planet: In winter and in the summer in the Arctic, we either have darkness or light.