According to scientists, the earth's crust consists of seven giant plates that are not connected. Under them is the mantle. These plates slowly "float" on the mantle, as if by sea. Moving, they face each other, and it causes an earthquake. To prevent earthquake impossible, but to predict it and to warn people scientists.
Using devices seismographs scientists monitor the state of the planet. As in any place of the Earth origin of the earthquake, from him in all directions, fleeing seismic waves. These waves are caught by seismographs, and the scientist becomes clear in what place and at what power to expect aftershocks. If you expect a strong earthquake, they warn people to avoid human casualties. However, it is not always possible to make it on time. Yes and force of the future earthquake is not always possible to calculate.
Are there any other signals that advance warning of earthquakes? There! These animals. Many of them (dogs, chickens, pigs, rats) are beginning to show signs of anxiety for a few hours before the earthquake. Local residents in earthquake-prone areas trust these signs.