Grunting For Worms: Seismic Vibrations Cause Diplocardia Earthworms To Emerge From The Soil

Harvesting earthworms by a practice called 'worm grunting' is widespread in the Southeastern USA. The technique involves rhythmically scraping a wooden stake driven into the ground with a flat metal object.


A common assumption is that vibrations cause the worms to surface, but this phenomenon had not been studied.


We demonstrate that Diplocardia earthworms emerge from the soil within minutes following the onset of seismic vibrations caused by grunting.


The results are discussed in relation to two hypotheses: that worms are escaping vibrations caused by digging foragers, and that worms are surfacing in response to vibrations caused by falling rain.


Royal Society Journal Biology Letters


Biology Letters publishes short, innovative and cutting-edge research articles and opinion pieces accessible to scientists from across the biological sciences. The journal is characterised by stringent peer-review, rapid publication and broad dissemination of succinct high-quality research communications.


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