You might not know this, but bumblebees are very smart creatures with good memories. They can remember the colors, patterns and scents of a variety of flowers and fly long distances to and from those flowers as they collect their pollen.
Perhaps that's why it's not surprising that like humans, bumblebees are susceptible to false memories.
People forget things all the time, or remember them incorrectly. Recent high-profile court cases attest to this. Now we know the same is true for bumblebees.
In their experiments, Queen Mary University of London researchers Lars Chittka and Kathryn Hunt first trained bumblebees to expect a reward from a yellow artificial flower. Then, they added a second flower to their test: a black and white ringed flower. They followed that up by adding a flower combining elements from the previous two flowers, one with yellow and white rings.
The bees quickly learned, though, that when exposed to all three flowers, the yellow ones provided the reward. Their short-term memories continuously led them to those particular flowers.
However, several days after the initial training, the bees eventually became confused. In the beginning, they still flew towards the yellow flowers, but by the end of the day, they started going to the yellow and white flower, although it wasn't present in their first training session.
"We discovered that the memory traces for two stimuli can merge, such that features acquired in distinct bouts of training are combined in the animal's mind," says Lars Chittka of Queen Mary University of London. "Stimuli that have actually never been viewed before, but are a combination of the features presented in training, are chosen during memory recall."
This is the same phenomenon that happens in humans, too, the merging of long-term memories that sometimes lead to false memories. Scientists believe this is because the memory is adaptive, specifically when considering that those who learn object classifications better than others are often the ones more likely to have false memories.
This is even more present in bumblebees, who have more limited brain capacity than humans.
"There is no question that the ability to extract patterns and commonalities between different events in our environment [is] adaptive," says Chittka. "Indeed, the ability to memorize the overarching principles of a number of different events might help us respond in new situations. But these abilities might come at the expense of remembering every detail correctly."
