michael sylvester wrote, "A species of dolphins in India have a unique way of sleeping: they alternate REM in both hem-when one side of the brain is asleep the other side is awake. This could be construed as a survival tragedy to prevent drowning."
Actually, unilateral sleep is not at all uncommon. It's been described in cetaceans, pinnipeds, and the sirenidae as well as in birds. Many birds do it. I rember a neat study that found that when birds are sleeping in a row (e.g., ducks on a log or pigeons on a ledge), the birds in the middle of the row exhibit sleep in both hemispheres while those on the ends sleep with only one hemisphere and which hemisphere dends on which end of the row they are on. The idea is that you want to keep vigilance on the side on which you have no neighbor. e.g., See Unilateral Eye Closure and Interhemispheric EEG Asymmetry during Sleep in the Pigeon (Columba livia) Niels C. Rattenborg, Charles J. Amlaner, Steven L. Lima http://content.karger.com/produktedb/produkte.asp?typ=fulltext&file=bbe58323 Ed Edward I. Pollak, Ph.D. Department of Psychology West Chester University of Pennsylvania ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Husband, father, grandfather, biopsychologist, & bluegrass fiddler...... in approximate order of importance. --- You are currently subscribed to tips as: [email protected]. To unsubscribe click here: http://fsulist.frostburg.edu/u?id=13090.68da6e6e5325aa33287ff385b70df5d5&n=T&l=tips&o=868 or send a blank email to leave-868-13090.68da6e6e5325aa33287ff385b70df...@fsulist.frostburg.edu
