There are plenty of theories that suggest abused children are more likely to carry out abuse themselves when they grow up. Now it appears that pattern may exist in non-human species.
Researchers from Wake Forest University in North Carolina made the discovery while studying Nazca boobies, a bird found on islands in the Pacific ocean towards the west coast of South America.
The parent birds often leave children unattended while feeding, which leaves them prey for other adults to raid the nest, often carrying out physical or sexual abuse.
A team led by Martina Muller and David Anderson, who have been studying the birds for several years, tracked such behavior by marking chicks and keeping record of attacks. They found a “strong correlation” between chicks being abused and then committing abuse when adults.
According to the team, it is much more likely this is caused by the life experiences rather than being a genetic pattern. They suggest it’s a (literally) vicious cycle of stress hormones being raised and then triggering violence in later life.
Anderson told the BBC the birds could be particularly useful for studies into the “cycle of violence”. That’s not just because the pattern is quicker to emerge than with humans (the entire life expectancy of a booby is only around 17) but, as Anderson explained, because it’s easier to carry out manipulative studies that would be neither ethical nor practical among humans.
(Image credit: Ernie Lo, used under Creative Commons license)