Do fish and/or dolphins sleep?

Question

if so, do they stay at the bottom of the water?

Answer 1

Fish have swim bladders that enable them to sleep while floating. Unfortunately, sharks don't have the swim bladder, so they have to continue swimming and swimming, otherwise they'll sink and drown.

Answer 2

lol..... what would happen to a dolphin if it slept on the bottom of the ocean?  Last I checked they still breath air.

Answer 3

Dolphins brains have 2 halves that function seperatley. While one half is asleep the other is functioning and vice versa. Their brian hemispheres function independently.

Answer 4

Fish do 'sleep' in their own way, having distinct periods of activity and inactivity.

Dolphins have to be conscious to breath. This means that they cannot go into a full deep sleep, because then they would suffocate. Dolphins have "solved" that by letting one half of their brain sleep at a time. This has been determined by doing EEG studies on dolphins. Dolphins sleep about 8 hours a day in this fashion.