UK Coastline – A new study from the University of Plymouth reveals that hermit crabs with more sensitive claws boldly emerge from their shells faster after being startled.

These tiny crabs, common in UK rockpools, constantly scan their environment for danger. When frightened, they retreat into their shells but use sensitive hair-like structures on their claws called sensilla to decide when it’s safe to come out again.

Researchers found that crabs with more sensilla recovered quicker from fear, marking them as braver and more consistent in their behavior. The study, published in the Proceedings of the Royal Society B, sheds light on how these sensory hairs help crabs better assess threats.

Lead author Ari Drummond said her observations of crabs using claws and antennae to explore inspired the research. She stressed the importance of understanding how animals sense and react in a changing environment.

The team analyzed moulted claw tissue using advanced microscopy to count sensilla without harming the crabs. Senior author Mark Briffa noted this connection between sensory ability and boldness has been overlooked and may extend to other animals.

The researchers propose the idea of a “sensory investment syndrome,” exploring how sensory traits shape animal personality and decision-making.

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