Fire ants form rafts to survive flooding by latching together to create a buoyant structure that keeps the colony united. The response of these living rafts has been the focus of research by Binghamton University Assistant Professor Rob Wagner. The goal is to understand how these rafts autonomously change and morph their mechanical properties and to apply these discoveries to artificial materials. Wagner is interested in the energy storage and conversion capabilities of living systems and sees this as essential to mimicking the smart and adaptive behaviors of these systems.
In a study published in the Proceedings of the National Academy of Sciences, Wagner and his team investigated how fire ant rafts respond to mechanical loads when stretched and compared this response to dynamic, self-healing polymers. They found that the mechanical response of the ant rafts remained consistent regardless of the speed at which they were pulled, unlike polymers that flow or break depending on the speed of the force applied. The researchers discovered that the bonds between the ants actually strengthen when force is applied, a phenomenon known as catch bond behavior. This behavior likely enhances cohesion within the colony and contributes to their survival.
Wagner believes that mimicking these catch bonds in engineered systems could lead to artificial materials that exhibit autonomous, localized self-strengthening in regions of higher mechanical stress. This could have applications in enhancing the lifetimes of biomedical implants, adhesives, fiber composites, soft robotics components, and other systems. Collective insect aggregations like fire ant rafts are already inspiring researchers to develop materials with stimuli-responsive mechanical properties and behaviors. Recent research led by the Ware Responsive Biomaterials Lab at Texas A&M and including contributions from Wagner demonstrates how ribbons made of special gels or liquid crystal elastomers can coil due to heating and entangle with each other to form solid-like structures inspired by fire ants.
Wagner’s research focuses on understanding the adaptive responses of living systems, such as fire ants, and incorporating these mechanisms into artificial materials. He is particularly interested in the unique energy storage and conversion capabilities of living systems, which are not present in traditional engineered materials. His work on catch bond behavior in fire ant rafts could lead to the development of artificial materials that exhibit self-strengthening properties under mechanical stress, similar to living systems. This research has the potential to improve the performance and longevity of various engineered systems and devices.
The investigation into how fire ant rafts respond to mechanical loads has provided valuable insights into the behavior of living systems and the potential applications of these behaviors in artificial materials. Wagner’s research has shown that the bonds between fire ants actually strengthen when force is applied, a phenomenon that enhances cohesion within the colony and contributes to its survival. By mimicking these catch bonds in engineered systems, researchers hope to create artificial materials that exhibit autonomous, localized self-strengthening properties under mechanical stress, which could have a wide range of applications in various industries.
Overall, Wagner’s research on the adaptive responses of fire ant rafts and the incorporation of these mechanisms into artificial materials has the potential to revolutionize the field of materials science. By understanding and replicating the unique energy storage and conversion capabilities of living systems, researchers hope to create artificial materials with improved performance and longevity. The study of catch bond behavior in fire ant rafts is just one example of how researchers are drawing inspiration from nature to develop innovative solutions in materials science.