Summary
Researchers placed electrodes in a pool with a dolphin. When activated, the electrodes created a weak electric field, causing the dolphin to swim away. When they were not activated, the dolphin behaved normally. After covering the dolphin's vibrissal crypts with a plastic shield, the dolphin no longer swam away when the electrodes were activated.
Strongly Supported Conclusions
The vibrissal crypts impact a dolphin’s ability to detect electric fields.
Dolphins instinctively swim from electrical fields
Dolphins instinctively swim from electrical fields
A
In the wild, dolphins sometimes encounter strong electric fields.
There is no information about this in the stimulus. You have to assume that because they have vibrissal crypts, there are strong electric fields in the wild.
B
Vibrissal crypts enable dolphins to sense electric fields.
The experiment showed that the dolphin no longer reacted to the electrical field when the vibrissal crypts were covered. It is reasonable assume that the crypts impact the dolphin’s ability to sense electric fields.
C
Dolphins do not instinctually avoid electric fields, but they can be trained to do so.
This is antisupported. The study showed how the dolphins instinctively avoided the electric fields when they were present.
D
Electric fields interfere with the normal functioning of dolphins’ vibrissal crypts.
This is antisupported. The plastic shields interfere with the normal functioning of vibrissal crypts. That’s why the dolphin no longer avoided the electrical field.
E
Under normal circumstances, dolphins are unable to sense electric fields.
This is antisupported. Dolphins are normally able to sense electric fields. It is only when their vibrissal crypts are covered that it no longer detected them.