Eve Gersh – Bee Campus USA Eco Rep
If flying up to ten miles a day, a distance more than 100,000 times your body length, sounds like hard work: that’s because it is. Yet, foraging honeybees do this daily to contribute to their honey stores for the hive. It is no wonder they need to sleep at night. While this is a logical conclusion, the scientific community did not have much data to support bees’ need for sleep until 1983, when Walter and Jana Kaiser’s research on sleeping bees was published.
In their experiments, the Kaisers tested the effects of sleep deprivation on bees. When bees were not allowed to sleep, their waggle dances became sloppy, which led other bees to the wrong foraging locations. They also needed to spend more time orienting themselves when returning to the hive, and, in some cases, they even got lost and were unable to return.
The Kaisers also found that older bees needed more sleep and that bees slept in certain locations of the hive depending on their responsibility. For example, older foragers tended to sleep towards the outside of the hive, away from the cluster. While there is no answer as to why that is, there is some speculation that older bees may need to get away from the business of the crowd or that sleeping on the outside of the cluster best insulates the vulnerable larvae from diseases and parasites.
Like sleeping humans, a sleeping bee’s body temperature drops, and a certain signal pattern is noticeable in her brain. Honeybees are not the only ones who need sleep. Bumblebees also sleep and have even been found napping in flowers. A group of Israeli researchers found that bumblebees give up sleep to tend to young larvae even when the larvae are not their own.
What happens inside the mind of a bee while it is sleeping remains a mystery. Perhaps they are processing memories of the day, such as where the best nectar flow was. Maybe their bodies use the downtime to repair cells and build their immune systems. Or, could it be that these little insects are dreaming?
Sources:
Kaiser, W., Steiner-Kaiser, J. (1987). Sleep Research on Honeybees: Neurophysiology and Behavior. In: Menzel, R., Mercer, A. (eds) Neurobiology and Behavior of Honeybees. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-71496-2_10
“Where do bees sleep?” MyBeelineBees, 8 June 2017, http://www.mybeeline.co/en/p/where-do-bees-sleep#:~:text=But%2C%20even%20though%20that%20seems,some%20bees%20even%20fall%20sideways.
Gander, Kashmira. “Bumble Bees Give up Sleep to Care for Young, Even When They’re Not Their Own.” Newsweek, Newsweek, 3 Oct. 2019, http://www.newsweek.com/bees-lose-sleep-caring-young-1461997#:~:text=A%20study%20has%20revealed%20that,Almost%20all%20animals%20sleep.
Nagari, Moshe, et al. “Bumble Bee Workers Give Up Sleep to Care for Offspring that Are Not Their Own.” ScienceDirect, vol. 29, no. 20, 3 Oct. 2019, doi:https://doi.org/10.1016/j.cub.2019.07.091.
Burlew, Rusty. “Do honey bees sleep? Of course they sleep!” Honey Bee Suite, http://www.honeybeesuite.com/do-honey-bees-sleep-of-course-they-sleep/.
The Wonderful World Of Bees, BuzzAboutBees.Net, 12 Feb. 2021, http://www.buzzaboutbees.net/do-bees-sleep.html.
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