Q) Why are other primates so much stronger than us?
Jim Wells, Chicago, Illinois
A) YOU MUST BE talking about the great apesgorillas, orangutans, and chimpanzees. On a pound-for-pound basis, apes do have more muscle than humans, says Adrienne Zihlman, an anthropologist at the University of California at Santa Cruz. Our muscle fibers are virtually identical and can exert the same force per unit of muscle mass, but apes have about 7 percent more muscle tissue per pound of body weight, most of it housed in the upper body. Since apes walk on all fours, they have long, extremely burly arms, which constitute 18 percent of their body weight, compared with 8 or 9 percent for us. Their hands are two to three times heavier, and their bones and torsos more robust. Turning to a more visceral definitionwho could kick whose hineyour more agile cousins don't share the human tendency toward physical inhibition and, if threatened, will grab, hold, bite, and punch with reckless abandon. (That's why it's called "going ape.") If it makes you feel better, our legs are much stronger. So should you ever encounter a hotheaded chimp with his dukes up, just hightail it back the way you came. You're no Tarzan.
Q) How fast would you have to fly a plane to keep a perpetual sunset before your eyes?
Jeff Beck, New Orleans, Louisiana
A) LOOKING TO prolong the cocktail hour, eh? To keep the sun on the western horizon, you have to fly as fast as the earth is rotating at your latitude. Sunset chasers at the equator can simply divide the circumference of the earth24,902 milesby 24 hours to find their answer: 1,038 miles per hour. As you move to higher latitudes, the surface's rotation speed drops. In your case, at 30 degrees north latitude in N'Awlins (where the circumference is 21,600 miles), your eternal-propulsion craft would need to go about 900 mph, or 1.4 times the speed of sound. After the 1,350-mph Concorde is retired this month, there will be no commercial flights moving at such speedsand, no, we don't recommend stealing an F-22. So head farther north. A 747 traveling from Oslo to Anchorage at the 60th parallel (circumference = 12,450 miles) would have to fly only 520 mph, well within its cruising speed of 570 mph. Another option: Take a trip to the North Pole in the fall. There, you can watch the sunset from the relative comfort of your igloo for about 30 days straight.
Q) What does it mean when a squirrel chatters at me?
Maria Ricapito, Brooklyn, New York
A) THIS LONG multisyllabic call means different things for different squirrels. First there's the ground squirrel; females of this variety live in close-knit groups, or "coteries," while the males are always off doing their own thing. As Cornell University animal behaviorist Paul Sherman explains, when a slow-moving predator (like you) seems to be posing a threat, one of the females starts chattering as a heads-up to the others. In some cases, he says, this represents a "selfless act of nepotism," in that the chatterer, by becoming the center of attention, gives its life to allow its kin to escape. Then there's the individualistic tree squirrel; for these rodents, the chatter seems to be a way of telling a large animal "I see you; don't waste your time trying to catch me." The noise is just one of several barks, squeals, and cries in a squirrel's vocabulary; others connote "I'm angry," "Time to come home, Junior," and "I've just mated with her; keep your mitts off." When a squirrel spots a truly scary predator, like a hawk, it emits a high-pitched shriek. For ground squirrels, this creates pandemonium, as the critters all start squeaking and scrambling for cover. The more aggressive tree squirrel hopes it will dissuade the hunter from attacking. When this doesn't work, he tries that old standby, running.