If you were anything like me as a kid, a huge Finding Nemo fan (“Fish are friends, not food”), you probably recall that one scene: Marlin, exhausted and heartbroken after his long search for Nemo, swims past two crabs perched on a pipe, happily snacking on bubbles. Earlier, those crabs had already defended their spot from a rival with a series of dance-like moves – and later, they react in much the same way to both Marlin and Nemo.
But what does science say about this behaviour?
Do crabs really dance?
The short answer is: Yes, it seems like some of them do dance. But like so many things, this insight is more complex than it appears at first glance.
Dancing Kings
Unlike us humans, crabs (at least according to current research) don’t dance out of joy or passion – yet. Instead, they move in ways that serve a purpose: to avoid other crabs or to impress potential mates. (Okay, maybe that last one is something we possibly share with them sometimes)
A study from 2001 by the Department of Zoology at Kyoto University revealed that one species of ghost crab (Ocypode stimpsoni) combines visual claw-waving with acoustic signaling. Males, with their oversized claw, tap it against the sand to create two distinct sounds: “rapping” (slower movements) and “quivering” (rapid vibrations at about twice the frequency). Researchers observed that this display intensifies when another crab comes too close: more waving, higher gestures, and a whole lot more noise.
According to a 2008 paper by Clayton from Sultan Qaboos University, another ghost crab, Ocypode platytarsus, performs the most elaborate mix of visual and acoustic displays in their genus. They produce sounds in three ways: tapping the ground with one claw, drumming with both claws, and through a kind of dance that generates vibrations. When a wandering crab approaches, the males rise tall on extended legs, perform rapid steps in place that morph into swift sideways movements, and eventually circle their “audience” in full arcs. This performance produces a distinctive audible and vibratory signal, different from the sounds made by claw tapping alone.
And then there’s the banana fiddler crab (Uca mjoebergi).
Picture this: up to 100 males packed into a single square meter, all waving their claws in what looks like unintentional synchronized choreography.
For some of you dancers, this may seem impressive and make you smile, but for the females watching, this group effort is often a total fail. They actually prefer the rebels: males that wave off-beat or against the rhythm of the crowd.
So yes, there really are crab species whose movements look like playful dances to us. But beneath the humor lies serious behaviour: driving away intruders or stubbornly (and sometimes unsuccessfully) trying to win over females. Just like us, in their own quirky way. Stay tuned, because who knows what other crab “dance moves” science will uncover in the future. We will let you know.
Article by Katharina Gföller, Photos by Sabine M. Probst Saavedra