The Simple Algorithm That Ants Use to Build Bridges (2018)

Army ants exhibit remarkable collective behavior by building bridges using their own bodies, despite lacking a leader or complex cognitive abilities. Research led by Simon Garnier from the New Jersey Institute of Technology reveals that these ants follow simple rules to coordinate their actions. When an ant encounters a gap, it slows down, and as other ants walk over it, it freezes in place. This process continues, allowing the ants to form a bridge long enough to span the gap. The study also highlights a trade-off in bridge construction; ants do not always choose the shortest route, suggesting a cost-benefit analysis at play. The cost involves ants being occupied in bridge-building, which limits their availability for other tasks like foraging. The researchers found that up to 20% of a colony can be engaged in maintaining bridges at any time. Additionally, ants have a sensitivity to foot traffic, allowing them to unfreeze and rejoin the march when the pressure decreases. This research, based on observations in the Panamanian jungle, aims to predict when ants will build bridges versus taking a longer route. The findings contribute to understanding swarm intelligence and may inform the development of simple robotic systems that mimic these natural behaviors.

- Army ants build bridges collectively without a leader using simple behavioral rules.

- The construction process involves trade-offs between efficiency and resource allocation.

- Up to 20% of a colony can be engaged in bridge maintenance at any time.

- Ants exhibit sensitivity to foot traffic, influencing their decision to build or unfreeze.

- The study enhances understanding of swarm intelligence and potential applications in robotics.