Scientists have found that baby birds who are bullied and abused by older birds are more likely to grow up to become bullies and abusers themselves. Researchers studying a colony of Nazca boobies, a colonial seabird, found the birds perpetuate a "cycle of violence". It is the first evidence from a wild animal that, as in humans, "child abuse" can be socially transmitted down the generations. Nazca boobies are sea birds endemic to the Galapagos Islands, and other islands off the coasts of Ecuador, Peru and Colombia. Typically birds just raise one chick a year.
The birds nest within densely-populated colonies, and this proximity to each other encourages bouts of violence to break out. While parent birds are away feeding at sea, non-breeding adults seek out unguarded nests and attempt to interact with the chicks within, often turning violent. Researchers found that many of the baby birds – who were ringed at birth in order to be studied – then turned into violent and abusive birds themselves when they entered adulthood.