The Mystery of the Sleeping Dolphins

Dolphins are a favorite animal for most of us who have spent any significant amount of time in or around the ocean. Energetic, playful, friendly, and incredibly intelligent, they amaze us with their abilities and beauty. One of the enduring mysteries about dolphins has been their sleep habits. You never find a dolphin sleeping some place, and studies of them have shown that in essence they never stop swimming. There is no dolphin motel where they settle down for a long nap.

Studies of dolphins have shown that they do not sleep the way we do. When land mammals sleep the whole brain basically shuts down and goes through a series of steps that have been studied extensively by psychologists. Like us, dolphins have two hemispheres in their brain. When dolphins sleep, one hemisphere continues to function while the other sleeps. In fact the sleeping side's eye (which is actually on the other side of the body from that hemisphere) closes during this sleep period. The animal continues to function but simply swims in circles. In Natural History, July 8, 2000, pages 40-41, is a report about how the dolphins as a group handle this.

The report is of research done at the University of California at Santa Cruz on Pacific white-sided dolphins. The dolphins swim in a circle so that the open eye faces other dolphins in the circle. The circle is tight and because there is a large group of large animals, no predator is going to make an attack. Once the animals have reached their necessary amount of sleep, the school will break up its cycling as a group and the animals will continue their normal life activities.

The origin of a system like this is very difficult to comprehend evolutionally. The traditional model of cetaceans is that they were land animals that adapted to a marine environment, but this sleep behavior seems to be a special design feature that fits only schooling behavior in a marine environment where a particular need exists. Having a system that allows each animal to go to the surface to breathe, synchronizes sleep patterns to take care of one side of the brain at a time, and allows maximum security for all members of the group is truly a remarkable plan. We submit that designs of this complexity have their roots in a mind that designed the system to fit a particular need. God speaks to us even in the sleep of His creatures.

Back to Contents Does God Exist?, NovDec00.