Are ants solid, or a fluid? Ants clinging together in a ball act differently from an individual insect. Banded together, they change their nature. Ants are now being studied by physicists, namely Zhongyang Liu and David Hu of the Georgia Institute of Technology.
To flow, they moved around, rearranging themselves in the group, acting like a thick fluid. When the aggregation struggled to keep its shape, the ants clung to each other, acting like an elastic solid — rubber for example.
The research could have practical implications, Dr. Hu said, for self-assembling robots, which build themselves out of smaller bits and for self-healing materials.