Culture, in its most basic form, refers to the socially learned behaviors that are shared within a population. Until the middle of the 20th century, this ability was considered something uniquely human. But abundant evidence now shows that culture exists in a wide variety of species, from bighorn sheep and vervet monkeys to meerkats and cranes.
Scientists are even discovering that insects can join their own culture. in a new PLOS Biology study, the researchers used a gold standard test that was applied to species such as chimpanzees and great tits to reveal that bumblebees are capable of cultural transmission from one insect to another. Bees that learned one of two solutions to open a puzzle box spread that behavioral trait to untrained bees, creating a cultural signature for their colony. “It’s an animal with a brain the size of a pinhead, and yet they could achieve similar things [as] primates or birds, which is quite remarkable,” says lead author Alice Bridges, now a lecturer in animal biology and behavior at Anglia Ruskin University in England, who undertook the study in as part of his doctoral research at Queen Mary University of London.
Insects are known to be capable of social learning in nature: the best-known example is the so-called wriggling dance used by bees to communicate the location and quality of flowers. The new study builds on previous findings that bumblebees can also learn complex behaviors in the lab, such as accessing rewards by pulling strings Or rolling balls play some kind of insect version of football. These previous studies have shown that bumblebees are capable of social learning but not necessarily of culture, which involves the spread of a specific behavioral variant within a population. “We wanted to see if the bees would be able to maintain a cultural tradition, even when there was an alternative behavior they could adopt,” says Bridges.
She and her colleagues adapted a puzzle box design that had previously been used in experiments with primates and birds for their grape-sized study subjects. Bees could either push a red tab clockwise or a blue tab counter-clockwise to access a sugar solution contained on a yellow target below. The researchers selected demonstrator bees from four colonies to teach others and trained half of these demonstrators to access the reward under the red tab and the other half to access it under the blue tab. Next, the team returned the bees to their respective colonies, along with access to additional puzzle boxes.
As seen in other species, the researchers observed that the demonstrators proceeded to open the boxes in the manner they had been taught and that a subset of the colony mates of these bees learned to do the same by observing them. Bumblebees, like people, have different personalities when it comes to work, from highly motivated to lazy, Bridges says, and the bees in the first group tend to be the ones who learned the new behavior. Some go-getters took only a day to begin mimicking the protesters’ behavior and solving the puzzle, while others took up to four days. Occasionally, a bee would stumble over the solution to open the other colored tab that protesters in its colony had not learned to push. But the researchers found that this behavior did not hold and that these individuals always came back to open the tab corresponding to the behavior of their demonstrator bees, that is to say the culture of their colony.
In two control colonies in which bees were trained to recognize the yellow target as signaling a reward, but no demonstrator was trained to solve the puzzle, some insects figured out how to open the box on their own. However, they weren’t as competent as the bees in the experimental colonies that learned from the protesters. Of the control bees who figured this out, “most only did it a handful of times and then never again,” Bridges says. “So it was essential to have the social learning element to get the bees to continuously add box opening to their behavioral repertoire.”
This “exciting and groundbreaking study” takes evidence that culture is widespread in the animal kingdom “to new levels”, says Andrew Whiten, a cognitive ethologist at the University of St Andrews in Scotland, who was not involved in the study. research. “The authors were coy in not venturing to put the word ‘culture’ in their title, but if it had been me, I would have had it there.”
Bridges suspects that other social insects such as bees and leafcutter ants would show similar cultivation ability. As scientists continue to add species to the list of those that demonstrate such ability, these new findings show, she says, that culture is probably not the ‘evolutionary pinnacle’ that humans assumed. previously.
“Maybe the culture isn’t something super exclusive or difficult,” Bridges says. “Maybe the culture really isn’t all that.”