A new 20-year study highlights how superb starlings friendships are built not only on family ties but also on trust and mutual support. These African birds form strong social bonds and return favors over time, much like human friendships. The findings offer new insight into how animals work together and build long-term cooperation beyond blood relations.
Birds That Remember Who Helped Them
The study was based on 20 years of research in Kenya. Scientists followed superb starlings living in nine social groups. They tracked 410 nests and studied 1,175 birds using genetic data. What they found surprised them. Starlings were more likely to help specific individuals who had helped them before. These roles often reversed in later years—helpers became breeders, and past breeders returned the favor.
The behavior wasn’t random. It showed a pattern of give and take, similar to what we see in human friendships. If a starling helped raise someone else’s chicks one year, it was more likely to get help in return when raising its own chicks later.
Not Just About Family Ties
Birds in the same group often included both relatives and non-relatives. While starlings did prefer to help those they were related to—especially siblings—they also helped unrelated members. This is different from what scientists used to believe about animal cooperation.
For a long time, experts thought animals only helped family to pass on shared genes. But this study shows that superb starlings make choices based on past interactions, not just family ties.
Professor Dustin Rubenstein of Columbia University, one of the authors of the study, said, “They’re forming pairwise reciprocal relationships—if I help you now, you’ll help me later.”
Cooperation in Harsh Conditions
Superb starlings live in tough environments. Food is often scarce. Raising chicks takes a lot of effort. In many cases, it takes more than just two parents to raise young birds successfully. That’s where group support comes in. Extra helpers boost the chances of survival for chicks.
This is why building long-term bonds with group members—both related and unrelated—is so important. When starlings help each other, they create a system of trust and teamwork. That system helps the entire group survive through hard times.
Why Don’t They Cheat?
One big question remains: why do birds return the favor instead of just accepting help and then doing nothing? In other words, what stops them from “cheating” the system?
Dr Julia Schroeder, a behavioural ecologist at Imperial College London, said the study opens new doors. “It helps us better understand altruism and how it evolves. These birds likely recognise each other individually and build lasting social ties.”
The idea of animals keeping track of favors and returning them later suggests a level of memory and fairness once thought to be limited to humans and a few primates.
What This Means for Animal Science
The study, published in the journal Nature, challenges some key ideas in biology. It suggests that animals may form friendships based on experience, not just instinct or genes.
Scientists now want to explore how these bonds are formed. Do birds “remember” each other’s faces or voices? How long do they hold on to memories of past help? What happens if someone breaks the trust?
These questions touch on the heart of social life—both for animals and humans. Understanding how and why animals form friendships can help scientists learn more about the roots of human behavior too.
Superb starlings are not the only animals known to return favors. Dolphins, elephants, and some monkeys also show signs of social exchange. But this is the first time that such behavior has been documented in a wild bird population over a long period.
As the researchers continue their work in Kenya, they hope to find more clues about the role of trust and memory in animal societies. Their findings may one day change how we think about friendship, fairness, and cooperation—not just in animals, but in ourselves.