Ravens in stable social alliances will actively disrupt other relationships from forming in order to maintain social capital.
Researchers from the University of Vienna and the Konrad Lorenz Research Station worked with wild ravens in the Austrian Alps, studying over 300 individual ravens and noting the interactions between each bird.
Ravens form breeding pairs with territory, breeding pairs without territory, wooing pairs, or they are single. The status of the birds’ relationships determines their rank in the social hierarchy, with breeding pairs with territory up the top, and singles at the bottom.
The researchers recorded the birds’ interactions, including one-on-one grooming and play sessions — important for forming bonds — but they also observed many of these interactions being broken up by third party ravens.
Upon crunching the numbers, the researchers uncovered a social dynamic comparable to political strategy. The intervening ravens were those already in breeding pairs and the raven pairs getting interrupted were subordinates in the early stages of bonding.
The researchers suggest that the dominant breeding pair ravens (both male and female) were actively breaking up the subordinate ravens’ bonding sessions to preemptively stop relationships from forming. This way, the higher-ranking individuals with something to lose, i.e. territory and resources, could maintain that power without threat from a pair in the future.
In fact, intervening between bonding ravens is a gamble. 30% of the interventions involved the third party raven simply standing between the couple, presumably not making eye-contact to avoid awkwardness. But 70% of the interventions involved aggression, where the third party raven would aggressively break up the pair, sometimes resulting in a potentially damaging fight.
Living in large, complex social groups seems to necessitate a large, complex brain to deal with the other complicated individuals in the group. Recent research has also shown that ravens can remember their relationships for many years and even keep track of the relationships between other ravens. Our own big-brained family, the primates, have also been shown to engage in similar politics such as coalition forming, strategic killings, and complex relationship management.
This study shows not only social manipulation, but something more sophisticated: the preemptive stemming of threats before they occur, where the benefits are delayed, but the costs are immediate.
Feature photograph: Smithsonian’s National Zoo/Flickr
Research paper: Jorg J.M. Massen, Georgine Szipl, Michela Spreafico, Thomas Bugnyar. Ravens Intervene in Others’ Bonding Attempts. Current Biology, 2014; DOI: 10.1016/j.cub.2014.09.073