Sydney's smart and adaptable sulfur crested cockatoos to open trash cans in looking at each other.
You've heard of trash panda: raccoons looting garbage cans . How about yous garbage parrots?
Sulfur-crested cockatoos, which may seem exotic to Americans and Europeans, are everywhere in the Sydney suburbs. They have adapted to the human environment, and since they are known to be adept at handling objects, it is not entirely surprising that they have turned to a rich source of food. But you could say that the spread of their latest trick, to open the trash cans, puts an end to social learning and cultural evolution in animals.
Birds don 't only learn this skill by imitating others, which is social learning. But details of the technique evolve to differ among groups as innovation spreads, a mark of animal culture.
Barbara C . Klump, behavioral ecologist at the Max Planck Institute of Animal Behavior in Germany, and first author of a cockatoo research report in the journal Science , said: "This is actually a rather complex behavior because it has several steps. "
Dr. Klump and his colleagues
Some birds walk on the left, others on the right, they walk differently or hold head differently.The process is similar to the spread and evolution of human cultural innovations like language, or an execlassic mple of animal culture, bird song, which can vary from region to region in the same species.
Dr. Klump and his colleagues in Germany and Australia have traced the spread of behavior in greater Sydney over the course of two years. The behavior became more common, but it did not appear in random places, as it might have been if different birds discovered the trash technique on their own. It spread from its origin, indicating that cockatoos learned to do this from each other. Image One cockatoo did the job while others watched. Cre dit ... Barbara Klump / Max Planck Animal Behavior Institute
Cockatoos' new skill unlocks a whole new resource for birds. It is adaptive cultural evolution, spreading at lightning speed compared to biological evolution. Dr. Klump noted that culture has been called a second inheritance system and that applies to both humans andanimals, allowing us to adapt and quickly change our behavior.
It is impossible to know which bird or birds developed in first the trash can technique, but apparently there is not a single genie of the cockatoo. During the study, the behavior arose a second time in a suburb too far from the first for dissemination to be through social learning, Dr Klump said. The technique was invented again.
Scientists have observed social learning and what they call culture in primates, songbirds and other animals. Different groups of chimpanzees exhibit slightly different patterns of using tools, for example, as cockatoos did.
The researchers did not not just observed the different techniques in differentareas. They also tagged and observed around 100 of the cockatoos to better understand individual behavior.
They found that around 30 percent of the birds tried to 'open the trash and about 10 percent succeeded. Most of the successful birds were males. Dr Klump said men are successful because they tend to be bigger and are perhaps better able to cope with physical demands. Or they might have a higher rank and normally have first access to food.
But what about there any birds that weren't trying to open the bins? Were they just not smart enough or tall enough? Not necessarily, Dr Klump said, because once the trays were opened, any cockatoo could join in and feed. without having done any work. Maybe, she said, they have a sstrategy: "This bird can do it - I'll just wait for them to open it. " Whether this is true is a matter of future research.
Mark O 'Hara from the University of Veterinary Medicine in Vienna, who studies wild Goffin's cockatoos in Indonesia , said the study " beautifully combines citizen science with rigorous direct observations. "
He said he was particularly interested in the larger, higher-ranking parrots doing the job of exploiting the new resource. "In primates, " he said, "lower-ranking individuals would have to find new ways to access food, while the stronger dominant individuals could simply move and exploit these "discoveries ". "
The first species of parrot known to open trash was the New Zealand kea in a park. But in this case, Dr O 'Hara said, humans have stifled cultural evolution in the egg.
"It would have been interesting to see how the kea would have developed over time, but unfortunately the park was not too happy with the trash raids and changed the lids of the trash cans. "