Vulturine Guineafowl - Despotic leadership versus democratic decision-making

[Donkees]

Democratic decision-making allows subordinate vulturine guineafowl to regain control over collective group actions when dominants have a monopoly over resources

NOVEMBER 25, 2020
Behavioral Biology

Excerpt:

Scientists at the Max Planck Institute of Animal Behavior and the Cluster of Excellence Centre for the Advanced Study of Collective Behaviour at the University of Konstanz have studied the links between dominance and group decision-making in wild vulturine guineafowl. They report that democratic decision-making plays an essential role in mitigating the power of alphas by deciding where to move next if those alphas are monopolising resources.

While it had long been thought that alphas lead the way and decide where the group moves next, studies over the past decade have suggested that all group members can have equal say by ‘voting’ for where the group goes next. However, it has remained to be determined whether this form of democratic decision-making exists in order to keep the power of dominants in check. “Working together as a group is critical for these birds, as their bright plumage makes isolated individuals easy targets for predators such as leopards and martial eagles”, says Damien Farine, the senior author of the study and lead research on the vulturine guineafowl project.

The scientists found that who initiated, and therefore decided where the group moved to next, was dependent on the recent actions of the dominant group members. When groups were feeding in large spacious areas, where distributed food was equally accessible to everyone, then all group members contributed equally. However, when dominant individuals monopolised a particularly rich food patch – chasing other group members out – then the excluded subordinates combined their votes to move the group away from the patch, ultimately forcing the dominants to abandon their rich resources. These findings suggest democratic decision-making, as opposed to despotic leadership, has evolved so that all group members can obtain the resources (e.g. food and water) that they need to survive. This would not be possible if dominant individuals always decided what was best for themselves.

The researchers combined observations on foot, video tracking, and high-resolution GPS tracking across multiple groups of vulturine guineafowl, spanning several years. They first recorded all disputes between individuals birds to assign each animal a rank in the dominance hierarchy. They used an evaluation procedure common in chess, football, and table tennis used to assess players ranks based on who they lost and won matches against. The scientists also monitored which bird initiated departures from and to new feeding sites, and the order of individuals following from first to last.

https://www.mpg.de/16034177