Hyenas and their own Facebook algorithm ability

Aristotle, the legendary Greek philosopher, said, “Man is by nature a social animal.” We tend to seek human company and immediately bond with a person if he is already a friend’s friend. Perhaps it is the same philosophy that makes it so easy for social networking sites like Facebook to suggest friends to us who are already known to our friend.

With a simple click, a friend’s friend is soon in our intimate circle too. Incidentally, it isn’t just humans who seek companionship with like-minded individuals this way. It seems, spotted hyenas too make buddies with other hyenas that are already pals with their friends.

Scientists from the National Institute for Mathematical and Biological Synthesis of the University of Tennessee observed a clan of hyenas to understand their social behaviour over a period of 20 years. They found out that the ace predator, that usually lives and hunts in groups, relies on a network of trusted friends. And to increase this same network it usually bonds with another hyena that is a friend of a friend rather than any unknown hyena.

The triadic closure
The kind of behaviour in which a person bonds with friends of friends is known as the “triadic closure”. The research team found that the most persistent factor affecting the long-term changes in the social structure of spotted hyenas was the triadic closure.

Through years of evolution, the hyenas have figured out that trusting a known hyena is more advantageous to them then starting fresh with a stranger. “Cohesive clusters can facilitate efficient cooperation and hence maximise fitness, and so our study shows that hyenas exploit this advantage,” explains lead author Amiyaal Ilany.

Hyenas haven’t begun the use of Facebook yet and hence the next question that arises is: How do the animals distinguish who is a friend and who’s not? The answer lies in their acute ability to recognise maternal and paternal kin. The predator and the infamous scavengers of the Kenyan landscape live up to an average age of 22 years. They live in large clans that might have more than 100 individuals but being a part of a single clan doesn’t necessarily make them friends. A hyena will only become close to another hyena if it is linked in some way through kinship.

Scientists remark that although there are other factors such as sex, the social rank and environment effects like amount of rainfall that influence their social structure, the triadic closure is the most important. In hyenas, female members are dominant and remain in the same clan all their lives. The male members however, leave their clan as adults to search and join a new clan. In this new family, they are the lowest ranking members, which in simpler terms means last to get their share of the meal.

A male hyena has to wait for the older males to die or new males to arrive before his position in the clan is promoted. A female, however, is always assured of a stable place. Being dominant of the genders and living in the same clan, the social preference to remain with their kin or next of kin is more pronounced in females, but they display tendency over time to change who they are friends with.

For example, at one time, a female may care about the social rank, but she may later change her preference based on the amount of rainfall. A male member who has joined the clan and isn’t related is quite rigid in forming bonds and stays friends with the same members for a long time.

Family advantage
The advantage of living and bonding with familiar members is seen strongly when hyenas forage or hunt. Related females usually forage together and engage in coalitionary attacks against unrelated females when competing for food at a kill. Thus, females who associate with their female kin are able to gather larger amounts of food more efficiently.

In addition to allowing the head female to defend her rank, close associations among female kin allow some of these kin groups to displace higher ranking females under certain conditions. For the low ranking females associating with a higher ranking female ensures they will be safe and receive benefits through reciprocal cooperation.

The study doesn’t strongly relate the human attributes of social preferences with the hyenas apart from the choice of friendships. But if seen closely, it does allow to penetrate deeper into the same patterns and reasons why humans would be friends with a select few and not with others. Basic survival instincts of a social animal, whether human or hyena, makes us all a  part of the same behaviour clan.