Unlocking Bumblebee Behavior: How Facial Movements Reveal Their Inner Lives

Bumblebees enjoying sugar

Bumblebees Enjoy the Taste of Sugar

Dawn Monrose/Alamy

Recent studies indicate that bees display preferences beyond mere survival needs, suggesting a subjective experience akin to emotion. This groundbreaking discovery may alter our understanding of insect cognition.

While bees have previously demonstrated complex behaviors—such as counting and sensing rhythm—figuring out their emotional states has been challenging, as insects lack the nuanced facial expressions found in mammals.

“How do we interpret the behaviors of these hard-bodied insects with limited facial expressions?” questions Andrew Barron from Macquarie University in Sydney. “Do these bees experience internal states?”

To delve deeper, Barron and his team designed experiments involving buff-tailed bumblebees (Bombus terrestris).

The researchers provided the bees with sugary water droplets, alongside salty and bitter solutions, capturing their reactions on high-resolution video.


After tasting the sugar solution, bees exhibited frequent glossa extensions (the hairy tongue they use for nectar). Contrastingly, when presented with salty or bitter options, they responded by wiping their mouths and shaking their heads.

Bee Wiping Its Mouth

Southern Medical University Honey Bee Laboratory

Barron noted that these reactions might not directly indicate enjoyment; they could simply reflect responses to various chemicals.

The researchers then adjusted the sugar concentration, combining it with a bit of salt, which significantly reduced glossa extensions. Additionally, they exposed the bees to high temperatures (40°C/104°F) to mimic dehydration and then offered salty droplets, prompting them to poke out their glossa.

“Consider this: if I offered you an electrolyte drink after a heavy workout, you’d likely find it appealing. The internal state influences your perception,” Barron explains.

Bee Sticking Out Glossa

Southern Medical University Honey Bee Laboratory

In the final phase of the experiment, researchers sought to manipulate the chemistry associated with appetite and satisfaction in mammals.

When bumblebees received dopamine—known to influence motivation in mammals—their glossa protrusion remained unchanged, indicating a disconnect between desire and pleasure.

Conversely, administering endocannabinoids to honeybees, which enhance food enjoyment in mammals, led to increased glossa extensions.

“This suggests that insects like bees possess an internal life, evaluating and interpreting their surroundings. They are not simply automata adhering to preprogrammed responses,” Barron adds.

Ralph Adolphs from the California Institute of Technology highlights the study’s significance. “It showcases innovative research addressing a challenging subject,” he states, acknowledging the evidence supporting flexible behavioral responses in bees toward taste stimuli.

However, he questions if such evidence equates to the pleasure as humans understand it: “Facial expressions alone do not define emotions; people with facial paralysis also experience feelings,” he remarks. “One must conclude that bees may have their own unique emotional experiences, distinct from mammalian ones.”

Jonathan Birch from the London School of Economics noted this study was the first to untangle the bees’ “wants” from their “likes.” He concludes, “We often underestimate insects. We’re entering a fascinating era of research where advanced techniques reveal unnoticed behaviors, as evidenced in this study.”

Topics:

Source: www.newscientist.com

A bumblebee can survive underwater for a week while sleeping.

Bumblebees may be more resilient than previously thought

Aaron Bastin/Alamy

A lab error has revealed that hibernating bumblebees can survive for at least seven days even when completely submerged in water. This ability suggests that beleaguered insects are more resilient than previously thought.

Sabrina Rondeau I came across this discovery by chance while researching eastern bumblebees (St. impatiens) in a laboratory at the University of Guelph, Canada. One week, she was checking on the hibernating queen bees kept in a hibernation chamber, a tube filled with soil in the refrigerator, when moisture overflowed into the tube and four queens were submerged in the water. I noticed that I was sinking. “I was a little surprised,” she says. “I was sure the queens were dead.”

To everyone's surprise, after draining the water, the bees woke up unharmed. Rondeau had a hunch that undiscovered abilities were at work.

She systematically drowned 21 queens over seven days, and 17 of them, or 81%, survived the flood. “This is a very high survival rate, not much different than before. [hibernation survival] When there’s no water,” Rondeau says. This achievement is probably due to the fact that dormant bees reduce their metabolic rate. This means that bees require very little oxygen, which can be met by air stored within their bodies.

“Wow, the fact that you can submerge a land animal in water for a week and find that it's still alive is really amazing,” he says. Lars Chitka at Queen Mary University of London.

Male bees and worker bees die before the winter, but the queen bee endures the cold for up to eight months by hibernating, waking up in the spring to begin building a new nest. The number of queens that survive is directly related to future population growth.

These bees hibernate underground, so extreme weather can destroy their safe haven. “It's a pinch point in their life cycle,” he says Nigel Lane, Dr. Rondeau's supervisor at the University of Guelph, Canada. This is a problem because about a third of all bumblebee species are already in decline. Finding that they are physically adapted to survive potential flooding is “really, really good news,” he says.

topic:

Source: www.newscientist.com