QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by SMITH, A. M. Search for Related Content PubMed Articles by SMITH, A. M.

Journal of Experimental Biology 157,257-271 (1991)
Published by Company of Biologists 1991

NEGATIVE PRESSURE GENERATED BY OCTOPUS SUCKERS: A STUDY OF THE TENSILE STRENGTH OF WATER IN NATURE

ANDREW M. SMITH ¹

¹ Department of Biology, Coker Hall, CB 3280, The University of North Carolina Chapel Hill, NC 27559-3280, USA

The decrease in hydrostatic pressure generated by octopus suckers adhering to wettable and non-wettable surfaces was measured using a flush-mounted miniature pressure transducer. The cavitation thresholds, or lowest sustainable pressures, of sea water on the same surfaces were also measured and were compared with the pressures generated by octopuses. It is shown that suckers can generate hydrostatic pressures below OMPa on moderately wettable surfaces. This disprovesthe commonly repeated assumption that suckers cannot produce pressures below a vacuum and suggests that the importance of suction in attachment mechanisms may have been overlooked. On epoxy, the lowest recorded pressure was -0.168MPa (0.268MPa or 2.66atm below ambient), and the octopus generated negative pressure in 35% of the pulls that were considered maximal efforts. The suckers never generated negative pressures on non-wettable surfaces. These results are in agreement with the range of pressures that sea water can sustain on the same surfaces. It is suggested, therefore, that cavitation, the failure of water in tension, limits the attachment force of suckers. The difference between the cavitation threshold of water in nature and the cavitation threshold of pure water is discussed.

Key words: Octopus suckers, cavitation, pressure, adhesion, water

Accepted on December 17, 1990

This article has been cited by other articles:

				R. Holzman, S. W. Day, R. S. Mehta, and P. C. Wainwright Integrating the determinants of suction feeding performance in centrarchid fishes J. Exp. Biol., October 15, 2008; 211(20): 3296 - 3305. [Abstract] [Full Text] [PDF]

				W. Federle Why are so many adhesive pads hairy? J. Exp. Biol., July 15, 2006; 209(14): 2611 - 2621. [Abstract] [Full Text] [PDF]

				S. N. Patek and R. L. Caldwell Extreme impact and cavitation forces of a biological hammer: strike forces of the peacock mantis shrimp Odontodactylus scyllarus J. Exp. Biol., October 1, 2005; 208(19): 3655 - 3664. [Abstract] [Full Text] [PDF]

				W. M. Kier and A. M. Smith The Structure and Adhesive Mechanism of Octopus Suckers Integr. Comp. Biol., December 1, 2002; 42(6): 1146 - 1153. [Abstract] [Full Text] [PDF]

				G. K. Ellem, J. E. Furst, and K. D. Zimmerman Shell clamping behaviour in the limpet Cellana tramoserica J. Exp. Biol., February 15, 2002; 205(4): 539 - 547. [Abstract] [Full Text] [PDF]

				N. M. Holbrook, M. J. Burns, and C. B. Field Negative Xylem Pressures in Plants: A Test of the Balancing Pressure Technique Science, November 17, 1995; 270(5239): 1193 - 1194. [Abstract] [PDF]