It’s Not Just Humans: Bullied birds tend to grow up to be bullies themselves
Researchers at Wake Forest University in North Carolina have now learned that Nazca boobies perpetuate a “cycle of violence”: bullied chicks tend to become bullies and pass on the pain. When parent birds leave their nests to eat, baby boobies are often visited by sexually and physically abusive non-breeding adults; the chicks, when grown, are more likely to abuse unrelated chicks. “The link we found indicates that nestling experience, and not genetics, influences adult behaviour,” lead researcher David Anderson told BBC.
This behavior may have to do with hormone levels in the brain, according to another recent study out of Wake Forest University. Researchers found that concentrations of the stress hormone corticosterone in Nazca booby chicks increased five-fold during bullying events. The team believes that the spike in hormonal levels could have a long-term effect on the boobies’ brains, causing aggressive behavior later in life.