Researchers recently discovered what makes invasive fire ants so successful. They found that these ants are extremely sophisticated manipulators of sand and soil. They can build in any type of soil because they can excavate no matter the size of the grains. These ants are actually able to change their excavation technique to better suit the type of soil they are digging in. The researchers placed 100 ants in containers of different types of soil – small, medium and large grained, and let them excavate. They also placed ants in containers with different levels of moisture in the soil. The researchers found that that ants could build faster in coarser soil, but in the more moist coarse soil the ants tended to build more complex structures. Taking an even closer look, the researchers discovered that in coarse soil the ants will grab one particle and drag it with them as they shuffle backwards up the soil. When they are dealing with finer grains, they will pack two or three particles together, almost like they are making a snowball, and pick it up and march up the tunnel. Scientists hope the study will help them build better robots. How do you think studying the way these ants excavate their tunnels will help improve robotics?