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

Yes, I can see where this would be a handy skill. Unfortunately, unless your ancestors include birds or aquatic mammals, you’re not going to come by it naturally. One might try slicing one’s brain down the middle, thereby permitting the left and right hemispheres to operate independently, but I cannot in good conscience recommend this. So you’re stuck with No-Doz for now.

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.

The other night I was talking with a friend who worked at a bar in Arizona where most of the hicks got shots of tequila. As they got drunker they would ask to have “the worm” (bleagh) along with their shot. My questions are: What kind of worm is that thing? Does drinking/eating the worm make you drunker? And how did the worm end up in the tequila?

–Beth L. Grover, via the Internet

You probably think this is some ancient Mexican tradition, right? Not unless your idea of ancient is 1950. We even know who invented the practice. Various reasons are given for it, but I say it all boils down to: Let’s see if we can get the gringos to eat worms.

First let’s get a few things straight. There’s no worm in tequila, or at least there isn’t supposed to be. Purists (hah!) say the worm belongs only in a related product, mescal. Strictly speaking, mescal is a generic term meaning any distillate of the many species of agave (or maguey) plant, tequila included. Today, however, mescal is popularly understood to mean a product bottled in the region around the city of Oaxaca. For years this stuff was basically home-brewed firewater consumed by the locals, but in 1950, Mexico City entrepreneur Jacobo Lozano Paez hit on the idea of putting a worm in each bottle as a marketing gimmick. Stroke of genius, eh? I know, I don’t get it either, but that’s what separates us from the visionaries.

The critter in question is the agave worm, which is actually a butterfly larva. The worms bore into the agave plant’s pineapple-like heart, and quite a few get cooked up in the brew used to make mescal. Far from being grossed out of existence, Jacobo concluded that the worm was an essential component of the liquor’s flavor and color. He may also have figured, Hey, mescal is about as palatable as paint remover, and the only people who are going to drink this stuff are macho lunatics, so why not take it to the max? In fairness, the worms were also said to have aphrodisiac properties, and worms and bugs are sometimes consumed in Mexico as a delicacy. (Supposedly this dates back to the Aztecs.) At any rate, the ploy worked and the worm in the bottle is now a firmly established tradition.

The genuine agave worm is a bright coral color, which fades to pink in the bottle. Some bottlers substitute a species of white worm that lives in the leaves of the agave plant. Connoisseurs complain that the white worm isn’t as tasty as the red one, which to me is like complaining that your soup contains the wrong species of fly. I’ve had a sip or three of mescal in my day, and my feeling is, if you want to get sick, who needs a worm?

Art accompanying story in printed newspaper (not available in this archive): illustration/Slug Signorino.