The Pressure Sensitivity of Marine Invertebrates—a résumé after 25 years

Abstract

SynopsisEarly investigations into the effects of pressure on marine invertebrates were concerned mainly with determining limits of tolerance to extreme pressures, but within the last 25 years it has gradually emerged that many invertebrates are sensitive to quite small changes in pressure, often less than one atmosphere (1000 mb). The responses of most planktonic animals appear to be of a depth regulatory nature but certain littoral organisms show rhythmic changes in activity in response to cyclical pressure changes of tidal amplitude and frequency. The ecological role of such responses is considered.The parameters of the pressure sense are known only from behavioural studies and offer little information concerning the process of reception. A possible mechanism of transduction based on the compression of a surface film of gas is described.