The bees that stood on a ball.
Bumblebees were given a problem they had never seen before: a fake flower full of sugar water was placed just out of reach, & the only way to get it was to roll a wooden ball underneath it & stand on the ball like a step stool. Without any training, several bees figured this out on their ownâthe first time spontaneous insight has ever been shown in an invertebrate. That's an important distinction because the experiment emphasizes no former training, no trial & error, & no stepwise shaping. (That involves breaking down complex tasks into smaller, simpler & more manageable steps). The insight also requires a sudden, internally generated solution (the "Aha" moment), similar to the "Eureka! I have found it."
King Hiero II of Syracuse gave a goldsmith a certain amount of gold to make a crown. When it came back, it weighed the right amountâbut the king suspected the goldsmith had pocketed some of the gold & replaced it with less valuable minerals. To test the crown, Archimedes knew about water displacement dependent on the size of a substance (volume), not weight. Archimedes first compared the volume of the crown to the volume of a pure gold lump of the same weight. Immediately, he saw the crown displaced more water, meaning it was less dense & not pure gold. When he realized this, he was so excited that he ran through the streets stark naked, shouting, "Eureka! I have found it!" The bee's realization in the ball-rolling experiment is the same type of Aha! moment, just on a much smaller scale & in a very different brain.
German psychologist Wolfgang Köhler set up a famous experiment more than 100 years ago that changed how scientists understand animal intelligence & the power of insight or spontaneous problem-solving. The bee's remarkable insight is more similar to Wolfgang Köhler's chimp test, where a chimp wants to get a banana hanging too high to reach & is initially perplexed how to reach it. But then he sees boxes lying around, & without being taught, the chimp suddenly realizes that "if I stack the boxes, I can climb up & reach the banana," which he did & finally grabbed the banana. The experiment demonstrated that chimps were capable of insight. Both the chimp & the bee came to the same realizationâsame structure, same cognitive leap, except one was done by a chimp with a big brain; the other identical reasoning was done by an insect with a brain no bigger than a sesame seed.
Most animals can do problem-solving; insight is a step up because it's an understanding of cause & effect that does not rely on trial & error, copying others, or previous knowledge. Scientists have observed this ability in only a handful of vertebrate species (not invertebrates like bees), such as great apes, elephants & some birds (ravens & crows) & parrots. There is ongoing scientific debate over whether even more speciesâinvertebrates such as octopuses & certain spidersâshould also join the ranks of the spontaneous problem solvers, but until we have controlled conditions that challenge those species with the same paradigm, we won't know for sure. The bee result suggests that a tiny insect brain can support surprisingly flexible behavior. Bees do not normally move objects around to make platforms; this is not natural bee behavior. But the experiment shows that they can remember a hidden goal location & manipulate an object in relation to that goal.
In the 1st experiment, researchers built a circular arena about 4 in (10 cm) in diameter & 1.3 in (3.2 cm) tall, in which bees could walk but not fly. In the center, the team placed an artificial blue flower containing a sugary solution that was above their reach. They introduced a small wooden ball roughly 0.5-0.7 in (1.2-1.8 cm) that was light enough to push. Bees attempted to reach the flower but failed repeatedly. That's when the bee equivalent of Archimedes hit upon a brilliant idea. Use the ball as a ladder to get to the treat. The other bees then followed the innovator to get the sugar water on the fake flower. This shows us they have reasoning, they can innovate, & they can generalize (once they solve it once, they solve it faster the next time). Other clever insects include ants (navigation, using the Moon & celestial clues & path integration); honey bees (symbolic communication involving the waggle dance, which tells other bees where to go to forage); & jumping spiders that plan detours & have a visual working memory. However, spontaneous insightâthe "Aha!" momentâhas only been seen in bumblebees thus far.

















