Researchers have built a robot crab that can compete in claw-waving displays with real fiddler crabs, but "Wavy Dave" doesn't always come out unscathed.

In the new study, a robot crab—nicknamed Wavy Dave—waved its claw on a mudflat teeming with male fiddler crabs. The paper, published in the journal Proceedings of the Royal Society B, is titled "Biomimetic robots reveal flexible adjustment of sexual signaling in a wild invertebrate."