Limpets are renowned for their powerful attachments to rocks on wave-swept seashores: previous studies showed large limpets can withstand more than 80 kg of force. Unlike barnacles and mussels, limpets do not stick permanently to rocks; instead, they switch from strong attachment to free locomotion depending on the tide. Despite over a century of research, however, how the common limpet (Patella vulgata) achieves this feat remains unresolved.

In his latest paper, PhD student Victor Kang, in collaboration with Dr Birgit Lengerer (University of Mons, Belgium & University of Innsbruck, Austria) and Prof Patrick Flammang (University of Mons, Belgium), found that, contrary to common perception, suction is not the primary mode of attachment in common limpets. Rather, they secrete adhesive mucus that shares similarities with adhesive materials produced by other marine invertebrates for adhesion, like sea stars, sea urchins, sea anemones, and marine flatworms, which can move around, but not so much with adult mussels or barnacles, which adhere permanently. This suggests that there are certain molecular components which are more closely associated with mobile marine invertebrates than with those that adhere permanently to the surface.

This research is important because while strong and reversible adhesion to wet and slippery surfaces is a challenge for synthetic adhesives, limpets and other marine animals manage to do just that using adhesive materials. Insights into the composition of these adhesive materials and their function can one day inspire biomimetic adhesives that are effective on wet surfaces and are also biodegradable, such as in medicine or the food industry.

This paper was published by Royal Society Publishing Open Biology: Kang Victor, Lengerer Birgit, Wattiez Ruddy and Flammang Patrick, 2020 Molecular insights into the powerful mucus-based adhesion of limpets (Patella vulgata L.) Open Biol.10. 200019 http://doi.org/10.1098/rsob.200019