Humans not the only ones that pass down abusive behavior

(PhysOrg.com) -- In a recent study published in The Auk, researchers claim they have found evidence that humans are not the only species where child abuse is a socially transmitted behavior.

The study, conducted by Martina Muller, Dr. David Anderson and others from Wake Forest University looked at a colony of Nazca boobies found in the eastern Pacific and nesting on the Galapagos Islands. They studied the interactions of the birds for three breeding seasons and tagged new birds at birth.

These birds nest in large dense colonies where both parents typically raise a chick each year. But it is when these parents fly away to gather food for the chick that the violence starts. While the parents are away, the chicks are visited by other non-breeding adults. While these interactions can be positive, most of the time they are abusive in nature, with aggressive or sexual acts being taken out on the young chick.

By following these birds for three years, they found a connection between the amount of times these chicks were attacked and the frequency that they then attacked other chicks when they reached adulthood. The researchers believe that these attacks at a young age condition the birds for life and may affect other aspects of their personalities.

The researchers suspect that when the chicks are attacked on a regular basis, their level of stress is increased and stress hormones are released. These hormone levels then play a role in triggering aggressive behavior.

The scientists believe that this proves that the behavior is not genetic but a behavior that is influenced by the society in which the bird is raised. When looking at this ‘cycle of violence,’ researchers hope this model may be useful in the future in helping other studies looking at this phenomenon.

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