填空题 Vibrations in the ground are a poorly understood but probably widespread means of communication between animals.
It seems 11 that these animals could have detected seismic "pre-shocks" that were missed by the sensitive vibration-detecting equipment that clutters the world"s earthquake laboratories. But it is possible. And the fact that many animal species behave 12 before other natural events such as storms, and that they have the ability to detect others of their species at distances which the familiar human senses could not manage, is well established. Such observations have led some to suggest that these animals have an extra sense. The best guess is that they can feel and understand 13 that are transmitted through the ground.
Almost all the research done into animal signaling has been on sight, hearing and smell, because these are senses that people possess. Humans have no sense organs designed specifically to detect 14 vibrations. But, according to researchers who have been meeting in Chicago at a 15 of the Society for Integrative and Comparative Biology, 16 via vibrations of the ground (a means of communication known as seismic signaling) have been almost entirely 17 . These researchers believe that such signals are far more common than biologists had realized—and that they could explain a lot of otherwise 18 features of animal behavior.
A seismic sense could help to explain certain types of elephant behavior. One is an apparent ability to detect thunderstorms well beyond the range that the sound of a storm can carry. Another is the foot-lifting that many elephants display prior to the arrival of another herd. Rather than 19 the horizon with their ears, elephants tend to freeze their posture and raise and lower a single foot. This probably helps them to work out from which direction the vibrations are 20 .
A．vibration B．inexplicable C．symposium D．unlikely
E．terrestrial F．studied G．strangely H．overlooked
I．travelling J．interactions K．shakings L．scanning
M．shockingly N．studying O．conference