Is it true that ducks can have one side of their brain sleep while the other side remains awake? And how can I, as a struggling graduate student, learn to do the same thing? –Olivia, via AOL
Best of Chicago voting is live now. Vote for your favorites »
Birds and aquatic mammals are capable of unihemispheric slow-wave sleep (USWS), which means they can sleep with one eye open and one hemisphere of the brain awake. USWS helps aquatic mammals such as dolphins to keep breathing, presumably by permitting them to surface once in a while. It also enables birds to keep an eye out for predators–literally. This was demonstrated in an experiment that Nature reported earlier this year. Neils C. Rattenborg, a graduate student in the department of life sciences at Indiana State University, lined up four groups of four mallards. (Yes, he got his ducks in a row.) Then he videotaped the birds while they slept. He found that those on the ends of the rows–those more exposed to predators–had two and a half times as much USWS as the birds in the middle of the group. A bird on the end kept its outer eye (the one facing away from the group) open 86 percent of the time, whereas birds in the middle kept it open only 53 percent of the time. Brain-wave tests confirmed that half the brain slept and half was in a “quiet waking state,” alert enough for the duck to escape should danger threaten and maybe for him to scrape together an answer if called on in Western Civ.
–Beth L. Grover, via the Internet
