University researchers say pesticides keep bees from sleeping

Scientists from the University of Bristol have conducted research that shows common pesticides can prevent bees and flies from getting a good night's sleep. They say that just like humans, many insects need sleep to function properly. However, their sleep is impacted if they have been exposed to neonicotinoid insecticides, a common insecticide used worldwide.

Researchers have shown those insecticides impact the amount of sleep taken by both bumblebees and fruit flies, which could help understand why important insect pollinators are disappearing in the wild. Researcher Dr. Kiah Tasman said neonicotinoids the team tested had a significant impact on the amount of sleep the insects got. If the insect was exposed to a smaller amount of the insecticide, such as it might encounter on a farm, it slept less, and its daily rhythms were out of sync with the usual 24-hour cycle of day and night.

In the fruit fly, exposure to typical agricultural concentrations of neonicotinoids ruined the fly's ability to remember. Changes in the clock inside the fly's brain controlling its 24-hour cycle of day and night were also noted. According to the researchers, the fly's ability to tell time is essential for knowing when to be awake and forage. The team believes the insects were unable to sleep.

The bees and flies have similar brain structures, suggesting one reason why pesticides are so bad for bees is that it prevents them from sleeping properly and learning where food is in the environment. Currently, neonicotinoids are banned in the EU, and the researchers hope the ban continues in the UK as it exits the EU.

Bees and other insect pollinators are critical to growing plants around the world. Without pollinators, plants, including food crops, would be significantly impacted.