Robotic male crabs try to impress a real female crab in a new study. PhD candidate Sophia Callander of the Australia National University, Australia, set up robotic crab claws around a real living female. In the experiment, the bots were set up in several ways. One group had identical robo-crabs waving at the same speed, whereas another was made up of small claws with larger ones.
The study placed the living female in the center of the robotic claws. The robots were then actuated to simulate the same mating dance performed by their living counterparts. Callander found that the female did not choose any one particular bot at distances greater than 50cm. However, at shorter distances, the robot with the biggest claw in a group of other smaller claws won the female's affection. See the above video.
In the wild, larger fiddler crabs team up to protect smaller and weaker males. Then the smaller ones tag along, making the big guy look the biggest. Fairly clever of the big crabs, sad for the little guys.
Eavesdropper