Bee larvae and pupae seem to secrete a chemical pheromone that has the same effect as a late-night cup of coffee on their nurses. Self-sacrifice for new babies is usually a labor of love by new parents, but when it comes to bees, those whose lives are sleep-deprived due to insomnia and who must feed the babies in the middle of the night are not even the parents. They are the brood-caring team of worker bees.
In a study which appeared last year in the journal Current Biology, Moshe Nagari and other researchers found that baby bees produce chemicals that keep their caretakers awake. Therefore, these “nanny-bees” get less sleep than other worker bees tasked with non-brood-related jobs.
The title of the study is Bumble Bee Workers Give Up Sleep to Care for Offspring that Are Not Their Own.
In this unrelated 7:33-minute video called Inside the Beehive by Frederick Dunn, we look at some different roles of honeybees in the beehive, including the role of nurse bee:
While he was a postdoc at the Hebrew University of Jerusalem, Moshe Nagari studied sleep and was curious about the sleep sacrifices animals sometimes make when they have important work to do, like moms caring for their young. Like killer whale mothers, who hardly sleep for weeks while they follow their baby cubs around.
Although the function of sleep is still unknown, what we do know is that without it, health and performance suffer, and survival becomes questionable in birds, bees or humans. One of the amazing findings from this study is that worker bees sacrifice themselves to such a degree for offspring that is not theirs.
Nagari shifted gears from killer whales to social bumblebees (Bombus terrestris). After the queen bee lays her eggs, some worker bees are assigned as nurse bees to the larvae. He confirmed that when nurse bees slept with the brood, they slept significantly less than other worker bees.
At first the researchers assumed that what was keeping the nurse bees awake was that the larvae were constantly demanding food, so they replaced the bee larvae with bee pupae, which is a developmental stage that needs less food.
To their amazement, the nurse bees staying with the pupae slept even less because these needed the bee equivalent of swaddling. So, they sacrificed their own sleep, in order to incubate the pupae. But the interesting thing was that the baby bees did not even need to be there. If the nurse bees surrounded themselves with the cocoons where the pupae had been resting, these caretaking bees stayed awake and stayed on their bee-tippy-toes.
This led the researchers to the suggestion that baby bees secrete a chemical that works on worker bees as if they just drank a cup of java in the wee hours.
If correct, this is early evidence that juvenile bee pheromones can modulate the sleep of adult nurse bees, and possibly also in other animals, which interferes with the adults ability to sleep.