Steven Pinker -- How the Mind Works - Hampshire High Italian ...

Revenge of the Nerds 181Audiences are incredulous. All that computation inside the little bittypinhead of an ant? Actually, as computation goes, this is pretty simplestuff; you could build a device to do it for a few dollars out of little partshanging on the pegboard at Radio Shack. But intuitions about the nervoussystem have been so impoverished by associationism that a psychologistwould be accused of wild, profligate speculation if she were toattribute this machinery to a human brain, let alone an ant brain. Couldan ant really do calculus, or even arithmetic? Not overtly, of course, butthen neither do we when we exercise our own faculty of dead reckoning,our "sense of direction." The path integration calculations are doneunconsciously, and their output pokes into our awareness—and the ant's,if it has any—as an abstract feeling that home is thataway, yea far.Other animals execute even more complicated sequences of arithmetic,logic, and data storage and retrieval. Many migratory birds flythousands of miles at night, maintaining their compass direction by lookingat the constellations. As a Cub Scout I was taught how to find theNorth Star: locate the tip of the handle of the Little Dipper, or extrapolatefrom the front lip of the Big Dipper a distance seven times its depth.Birds are not born with this knowledge, not because it is unthinkablethat it could be innate, but because if it were innate it would soon beobsolete. The earth's axis of rotation, and hence the celestial pole (thepoint in the sky corresponding to north), wobbles in a 27,000-year cyclecalled the precession of the equinoxes. The cycle is rapid in an evolutionarytimetable, and the birds have responded by evolving a specialalgorithm for learning where the celestial pole is in the night sky. It allhappens while they are still in the nest and cannot fly. The nestlings gazeup at the night sky for hours, watching the slow rotation of the constellations.They find the point around which the stars appear to move, andrecord its position with respect to several nearby constellations, acquiringthe information imparted to me by the Cub Scout manual. Monthslater they can use any of these constellations to maintain a constantheading—say, keeping north behind them while flying south, or flyinginto the celestial pole the next spring to return north.Honeybees perform a dance that tells their hivemates the directionand distance of a food source with respect to the sun. As if that weren'timpressive enough, the bees have evolved a variety of calibrations andbackup systems to deal with the engineering complexities of solar navigation.The dancer uses an internal clock to compensate for the movementof the sun between the time she discovered the source and the time she