New experiments reveal that bumblebees alter their tongue movements based on internal conditions, pointing to subjective experiences similar to emotions.
Researchers at Macquarie University tested buff-tailed bumblebees with sugar, salt and quinine solutions. The bees extended their glossa after sweet tastes but wiped their mouths and shook their heads after bitter or salty ones. When dehydrated, the insects increased tongue protrusions even for salty water, showing their responses changed with internal state.
Treating the bees with dopamine boosted their motivation to seek food without altering tongue movements. Endocannabinoids, however, increased the protrusions linked to liking. Andrew Barron noted that these shifts indicate the bees evaluate their world rather than acting on fixed programs.
Experts including Ralph Adolphs and Jonathan Birch described the work as innovative. The study was published in PNAS under DOI 10.1073/pnas.2529114123.
