Scientists have identified a key factor that triggers social learning in wild animals. A study involving great tits has determined that immigration can lead these birds to closely observe others, allowing them to quickly adopt beneficial behaviors. This research is the first to provide experimental evidence supporting the long-held belief that immigrants should strategically utilize social learning. The findings were published on November 14 in PLOS Biology by scientists from the Max Planck Institute of Animal Behavior (MPI-AB) and the Cluster of Excellence Collective Behaviour at the University of Konstanz in Germany.
Scientists have identified a key factor that triggers social learning in wild animals. A study involving great tits pinpointed immigration as a reason for these birds to attentively watch others, enabling them to swiftly adopt advantageous behaviors. This research is the first to experimentally confirm the long-held notion that immigrants should strategically leverage social learning. The findings, conducted by researchers at the Max Planck Institute of Animal Behavior (MPI-AB) and the Cluster of Excellence Collective Behaviour at the University of Konstanz in Germany, were published on November 14 in PLOS Biology.
While many animals that gather in groups learn from each other, the great tit is a particularly insightful species for understanding social learning in the wild. Great tits gained notoriety in the 1920s when they learned to open the foil tops of milk bottles to access the cream inside. Initially observed in a small English town, this behavior quickly spread throughout Europe, raising questions about whether individual birds were inventing this technique independently or if they were learning from one another.
The mystery was only unraveled in 2015 when a research team led by Lucy Aplin—previously at the University of Oxford—conducted an experiment with a population of great tits in a forest in England. Aplin’s research demonstrated that these birds could learn to extract food from a puzzle box by observing other birds, confirming that the original bottle-raiding birds were passing their skills on to their peers.
“Social learning provides a valuable shortcut for exploring new situations safely,” explains Chimento, a postdoctoral researcher who was part of Aplin’s team at MPI-AB. “Observing the actions of others allows you to assess whether a new behavior is beneficial or risky. By mimicking what others do, you can also enjoy the rewards.”
Through imitation, animals can access new resources, prompting Chimento and Aplin to investigate whether there was an influential factor that could enhance social learning and help them discover these benefits more effectively. Theoretical frameworks suggested that animals might alter their social learning strategies when they encounter new environments. “When animals relocate, they might be more inclined to learn from others,” states Chimento, currently with the Cluster of Excellence Collective Behaviour at the University of Konstanz. Yet, he emphasizes that this had not been experimentally demonstrated in non-human animals before.
The researchers developed an automated puzzle box system to test the immigration hypothesis. They set up social groups of wild-caught great tits, assigning each group a trained tutor that accessed food by pushing the door either left or right. After releasing a tutor into each group, the team observed that the birds learned to prefer one method over the other.
Then came the immigration phase. Birds that had learned to push to the right were moved into aviaries occupied by birds that used the left-hand solution. Not only did the newcomers observe the residents opening the puzzle box in a different manner, but in certain groups, they also noticed that following the residents’ method led to better rewards.
“What stands out is that the immigrants were unaware that the food reward had changed,” remarked Chimento, the lead author. “They could only discern a difference by watching the resident birds interact with the puzzle or by experimenting with the other door themselves.”
And the immigrants did pay attention. After their release, a remarkable 80 percent of them switched their approach immediately. Instead of trying the method they had learned, these birds tried the resident solution on their first attempt. Chimento highlights that this significant result strongly suggests social learning was occurring: “While we can’t directly ask the birds about their sources of information, the striking behavioral changes imply that they closely observed the residents upon entering their new social group.”
Interestingly, these newcomers were not simply moved to an area where residents were obtaining better food; their visual environment was also significantly altered. The researchers manipulated the foliage in the aviaries where the immigrants were placed.
This modification in visual surroundings proved crucial for enhancing learning. In cases where the foliage remained unchanged, only 25 percent of the newcomers attempted the resident solution on their first try, despite observing the locals enjoying better rewards. “Although they weren’t ignoring the residents, it took them much longer to switch strategies. Our analyses indicated that they were less influenced by the residents in these trials,” Chimento explains.
This study provides the first experimental evidence demonstrating the substantial effect of immigration on how animals learn from each other, which could have significant implications in natural settings.
Aplin, the senior author of the study, states, “Animals frequently move between different environments in nature, so having an effective strategy to identify beneficial versus detrimental behaviors in new habitats is essential.” That’s why theories suggested that different learning approaches should develop as a filter for animals entering unfamiliar environments. “Our study validates that this phenomenon also occurs in real life,” she concludes.
