Tentacle Talk

Discolike dance moves may be cuttlefish communications

- Chris Simms

Cuttlefish wave their expressive tentacles in four distinctive dancelike motions, a new study finds possibly to communicate visually and by vibration.

These marine invertebrates, which have eight sucker-lined "arms" and two additional tentacles near their mouth, have been known to alter their body's color pattern to blend in with the background or create zebralike stripes to attract a mate. Some have been known to raise their arms to intimidate predators, and others to extend a particular arm to signal a mating desire.

But cognitive neuroscientist Sophie Cohen-Bodénès and computational modeler Peter Neri, both then at the École Normale Supérieure in Paris, noticed cuttlefish doing something that hadn't been described before: making specific, repeated and relatively complex arm gestures at one another.

Studying two species, common cuttlefish (Sepia officinalis) and dwarf cuttlefish (Sepia bandensis), the two researchers have identified four arm-waving signs, which they call "up," "side," "roll" and "crown." The scientists recently posted their observations on the preprint server bioRxiv.