MEPS 205:307-308 (2000)  -  doi:10.3354/meps205307

On the functional significance of masking behaviour in sea urchins—an experiment with Paracentrotus lividus

Heinz Richner1,2,*, Manfred Milinski1,3

1Station Biologique Arago, 66650 Banyuls-sur-Mer, France
2Department of Zoology, University of Bern, 3032 Hinterkappelen, Switzerland
3Department of Evolutionary Ecology, Max Planck Institute of Limnology, 24306 Plön, Germany

ABSTRACT: Much literature in marine biology describes the extraordinary behaviour of sea urchins, e.g., Paracentrotus lividus, who cover their body with shells, stones and debris. The function of this strange behaviour, described as Œmasking¹, is still a puzzle. Our experiment shows that sea urchins are loaded with more mussel shells when the delicate apical openings of their water vascular system which powers all their movements, are in danger of being occluded by floating sand. ŒMasking¹ shells appear to function as an umbrella against floating particles.


KEY WORDS: Masking behaviour · Cleaning · Paracentrotus lividus


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