Selfish Herding
Scientists have done tests to confirm an idea that has been around for 50 years on why herds form – because people are being selfish. Professor Clemens Bechinger, a physics professor at the Cluster of Excellence University of Konstanz’s Center for the Advanced Study of Collective Behavior (CASCB), says ending up with a fair situation in the herd even when people act out of their own self-interest is “surprisingly” possible. His team did research to prove this.
Scientists used a computer to understand how animals in a herd can protect themselves from becoming prey. The idea is based on something that W.D. Hamilton said back in 1971, which was that animals will bunch up so that they protect each other, even if it means that one of them has a higher chance of getting eaten. This study was published in the Journal of Theoretical Biology.
Lots of animals join together in groups, called herds. It’s not just because they like the company – it helps keep them safe. Take seals for example; when on their own, orcas and sharks can easily find them and hurt them. But if they stick close to each other, the danger of an attack is spread out. The safest place is right in the middle of a herd where everyone is all squished together – that way an attack targets your neighbor before you. At the edges of a herd though, there’s only few neighbors so it’s much riskier to be there. Each animal is trying their very best to get one of these spots in the middle!
Examining Selfishness in Animal Groups
Clemens Bechinger and his team used AI (artificial intelligence) to work out how individuals need to change their place in order to stay as far away from others as they can. Doing this reduces the chances of getting attacked.
Veit-Lorenz Heute, who’s doing a doctorate project, says that this strategy increases risks for nearby people and is considered “selfish”. As Hamilton predicted, the scientists saw that when individuals were spread out they ended up in a close herd because that lessened their risk of getting attacked by being closer to other people.
Professor Iain Couzin from the University of Konstanz says that research on reinforcement learning for groups is exciting and can help us to understand animal behavior better. This kind of research helps scientists ask questions about how animals get smarter when they’re in big groups, like herds or swarms. Surprisingly, after the group was formed, something unexpected happened.
The experiments showed that every animal has the same chance of being preyed upon. Animals in the middle of a herd are not safe as they have to constantly move away from other animals who also want to be in this prime spot.
According to Samuel Monter, who is part of the research team, it is difficult for individuals in a group to stay in the best spots. Another interesting thing they noticed is that the group almost acts like an animal herd as they all rotate around their centre point.
Our research has revealed that groups may form not only because of friendly interactions, but also from people’s selfishness to gain an advantage over the other. This will not just help us to understand how animals act together in groups, it can be used for programming autonomous robotic machines so they know what to do when doing tasks with a group.
Scientists have noticed that animals often move in swirling patterns called “vortices”. A recent study showed us why this happens – when animals come close to each other, it can reduce the amount of risk they are facing, but if they get too close then they will bump into each other and be penalized for it. This is why we see these vortices in things like fish schools and herd animals.
A new study called “Dynamics and risk sharing in groups of selfish individuals” was published in the Journal of Theoretical Biology on February 2, 2023. It was funded by a group called the “Center of the Advanced Study of Collective Behavior“. This paper studied how Middle East respiratory syndrome coronavirus has affected people from 2012 to 2020.
