Crabby Bellies

GRRR!!! Keep your distance!

This is Sandra Tsing Loh with the Loh Down on Science, saying…

Is that MY stomach growling? Sorry, I’m just hungry! But for crabs, that sound could mean they’re HANGRY! Think hungry AND angry!

Enter Jennifer Taylor from Scripps Institution of Oceanography and colleagues. They study a species of crab called Ghost Crabs. And they heard the critters making a low growling sound. Why…and HOW??

To find out, they placed ghost crabs inside acoustic chambers with objects such as a toy crab. They observed the crabs’ behavior and recorded sounds they made. A laser measured vibrations on the crabs’ shells to detect the source of the sound. 

Results? Crabs GROWLED when they felt aggressive. Growls and waving claws warn the toys to stay back! 

And WHERE was the sound coming from? Their STOMACHS!!

The researchers believe ghost crabs make these sounds by grinding teeth located INSIDE their stomachs. This noisemaking, along with waving their big, scary claws, turns these tiny critters into frightening monsters!

Don’t worry – MY growls just mean I’m hungry! Which makes me a little crabby. Just a little.

Reference: Taylor, J.R.A., DeVries, M.S., Elias, D.O. (2019). Growling from the gut: Co-option of the gastric mill for acoustic communication in ghost crabs. Proc. R. Soc. 286, 20191161 .

Image credit: Jennifer Taylor