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Ghost crabs growl using teeth in their tummy

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Ghost crabs growl like dogs using teeth in their stomach, according to international researchers. Ghost crabs, which are found in tropical waters around Australia, have evolved stomach teeth to grind up food. Now for the first time, international researchers have recorded evidence that they also use these teeth to growl during aggressive interactions. Since their claws are also used to communicate, the grumbling tummies are probably useful during close-up encounters when their pincers are busy, the researchers say.

Journal/conference: Royal Society B: Biological Sciences

DOI: 10.1098/rspb.2019.1161

Organisation/s: University of California, USA

Funder: This research was supported by a National Science Foundation (NSF) Minority Postdoctoral Fellowship (to J.R.A.T.) and the Marine Biology Research Division at Scripps Institution of Oceanography.

Media Release

From: The Royal Society

Growling from the gut: co-option of the gastric mill for acoustic communication in ghost crabs

Proceedings of the Royal Society B: Biological Sciences

Ghost crabs evolved stomach teeth to grind up food, but here we show that they also use these teeth to communicate acoustically during aggressive interactions, akin to the growling of canines. Animals have co-opted a variety of structures for sound production, but this is the first documented example of one using gastric sounds for communication. This discovery is especially interesting because crabs evolved specialized structures on the claws that provide a similar function. Thus, crabs display a unique redundancy of sound production mechanisms based on both novel and existing morphologies, which is unusual in the evolution of acoustic communication systems.


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