Figure 3.

Representative in vivo sub-pedal pressure values from P. vulgata with schematics showing the different trial conditions. (a) Free locomotion: small pressure values (around −0.02 to +0.07 kPa) were observed when the limpet was undisturbed and locomoting over the sensor. (b) Simulated attack: when a ball bearing was used to simulate a predation event, the pressure was lower, at around −1.0 kPa. This negative peak decayed slowly, taking around 7 s to reach approximately 60% of the minimum pressure. (c) Normal pull off: when the limpet was allowed to settle over the sensor and then manually detached perpendicularly (arrow marks beginning of detachment), a sharp negative peak was recorded that reached −5.7 kPa, which returned to zero when the limpet detached (marked Ø). All tests were conducted under water.