Popcorning' is the name for an unusual behaviour that many guinea
pigs exhibit, which involves them running backwards and forwards
rapidly, jumping into the air over and over again. Some cavies will
throw themselves straight up in the air, while some will alternately
kick their front and back legs out, almost like a bucking bronco. Often
they will make a squeaking sound at the same time.
Popcorning is particularly common in young babies, and is something
that both boars and sows do. Adult guinea pigs popcorn as well, although
generally not as often, and they don't jump as high as the youngsters. 4951