Can animals predict seismic activity before an earthquake strikes?
There are many theories and investigations that claim abnormal animal behaviour can help humans predict strong earthquakes.
The long-standing myth that animals can predict earthquakes is yet to be substantiated with scientific reasoning. But this has long captured the imagination of many as local accounts and eyewitness reports suggest that animals behave oddly hours or days before an earthquake strikes.
Dating back to ancient Greece, in 373 BC, it was said that rats, weasels, snakes, and centipedes migrated from their homes days before an intense earthquake jolted the entire region.
Similar anecdotes have emerged in recent times. Some say even fish and birds show unusual behaviour prior to seismic activity.
These stories have triggered the interest of researchers, who are using the latest technology to keep a tab on various animals that are said to predict earthquakes ahead of time.
The scientific inquiry
Martin Wikelski from the Max Planck Institute of Animal Behavior in Germany has led a significant investigation into changing behavioural patterns amongst a group of animals days before an earthquake struck their respective habitats.
Wikelski planted sensors on six cows, five sheep, and two dogs in quake-prone northern Italy. He observed them for several months before and during a series of earthquakes hit their habitat.
Wikelski and his team of researchers collected data that revealed a change in the behaviour of farm animals 20 hours before an earthquake. The animals showed an unusually prolonged activity time – they were 50 percent more active within a time frame of 45 minutes compared to previous days. With a series of calculations, the researchers rightly predicted an earthquake with a magnitude above 4.0. Using the same method, they predicted seven out of eight strong earthquakes.
American geologist Joseph L. Kirschvink explained this phenomenon in a scientific journal in 2000, saying many animals can sense the P wave seconds before the S wave strikes. P waves can travel through liquids, solids and gases, while S waves only travel through solids. A small number of humans can sense the smaller P wave that travels the fastest from the earthquake source and arrives before the larger S wave.
Kirschvin's study raises a crucial question: Is it possible for animals to develop a genetic tendency to forecast earthquakes and maintain this precautionary behaviour despite varying degrees of seismic activities? The natural instinct of all animals is to either defend themselves from predators or escape the impending dangers they cannot thwart.
The existing genetic makeup allows a wide variety of vertebrates to flag “early warning” behaviours for other types of events and it’s possible that some animals emulated that behaviour and transformed it into a seismic-escape response.
The contradiction
The scientific community is yet to have a consensus over animals predicting earthquakes, however.
Whit Gibbons, professor of zoology and senior biologist at the University of Georgia’s Savannah River Ecology Laboratory, tells to The Gadsden Times that survivors should appreciate can thank scientists for monitoring seismic waves in the earth’s crust, "not the odd behaviour of animals".
But a review of 180 publications reporting 700 records of abnormal or unusual animal behaviours prior to 160 earthquakes points to a significant correlation between these behaviours.
Although seismologists and scientists are yet to find a coherent pattern in using animal behaviour as one of the tools to forecast major quakes, more research into this phenomenon could lead the desirable results.