Figure 10.

Response to food and sulfide stimuli during experiments at in situ pressure on a batch of Rimicaris exoculata and Mirocaris fortunata. The shrimp were placed in the IPOCAMP aquarium for a recovery period of 2 h at 30 MPa and 10 °C (see Figure 4c for the setup description). Three gels (2 controls, 1 stimulus) were then introduced consecutively through an isobaric line with an interval of 45 min. The number of times of contact of the shrimp with the newly introduced gel was quantified over a period of 45 min (a) Rimicaris exoculata. Mean number of times of contact (±S.E.M.) with the stimulus (S, agarose gel loaded with a 2mM sulfide solution at pH11) and the control gels (C1 and C2, agarose gels). Three batches of 10 shrimp were tested once. The mean number of times of contact with the stimulus gel was compared to those of control gels with a two-tailed t-test for correlated samples (same batch of shrimp under different test conditions) (df = 2), and was not significantly different (NS) (S/C1, p = 0.068; S/C2, p = 0.098). (b) Rimicaris exoculata. Mean number of contacts (±S.E.M.) with the stimulus (S, agarose gel loaded with a 2mM sulfide solution at pH 4, black bar) and the control gels (C1, agarose gel, white bar; C2, pH 4 agarose gel, light grey bar). Three batches of 10 shrimps were tested once. The mean number of times of contact with the stimulus gel was compared to that of control gels with a two-tailed t-test for correlated samples (df = 2), and was not significantly different (NS) (S/C1, p = 0.901; S/C2, p = 0.965). (c) Mirocaris fortunata. Mean number of times of contact (±S.E.M.) with the stimulus (S, agarose gel loaded with mussel extract, black bar) and the control gels (C1 and C2, agarose gels, white bars). Two batches of 6 and 5 shrimp were tested once, and no statistical analysis was performed (n = 2).