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Fig. 2. Preventing aerial respiration for 3 days does not alter subsequent aerial
respiratory behaviour in the hypoxic training/testing apparatus. 12 snails
were tested (Before) in the hypoxic testing apparatus as described in
Materials and methods. 1 day following training they were placed for 3 days in
a eumoxic aquarium with a barrier that prevented them from reaching the
surface of the water, so that they could not perform aerial respiration. After
3 days the snails were tested (After) in the hypoxic training/testing
apparatus and responded no differently (paired t-test; NS,
P>0.05) than they did before being placed in a situation where
they were not able to perform aerial respiration.