For years, people have been talking about animals’ ability to predict earthquakes in advance. Many claim that their dogs, cats, and even cows started behaving erratically just minutes before the quake struck. However, a new statistical study debunks the theory and suggests there is no strong evidence to back the idea, except single observations and anecdotes that cannot be verified.

In order to come to this result, Heiko Woith and colleagues at the GFZ German Research Centre for Geosciences in Potsdam collected more than 700 reports of abnormal animal behavior related to earthquakes. This included dogs, cats, silkworms, elephants and a bunch of other animals who people said behaved unusually prior to a quake.

"Many review papers on the potential of animals as earthquake precursors exist, but to the best of our knowledge, this is the first time that a statistical approach was used to evaluate the data," Woith said in a statement. They found most of the reports were anecdotes from three major quakes — in New Zealand, Japan, and Italy — rather than experimental studies.

During the statistical analysis, the group did not find any similarity between the behavior of the animals. Some started acting weirdly months before the quake struck, while others reacted just a few minutes prior to the quake. Their distance to the origin of the earthquake also varied drastically — from a few to hundreds of miles.

Most importantly, of some 700 reports, only 14 were related to a series of animal observations, where the behavior was observed more than once.

That said, the information didn’t provide a solid, scientifically viable base to help researchers understand if animals had the ability to predict earthquakes before they begin.

GettyImages-874029008 There is not enough scientific evidence to confirm that dogs can predict earthquakes in advance. Pictured, an Iranian civil defense K-9 unit waits near damaged buildings during a search for survivors in the town of Sarpol-e Zahab in the western Kermanshah province, following a 7.3-magnitude earthquake that left hundreds killed and thousands homeless two days before. Photo: ATTA KENARE/AFP/Getty Images

However, the group does note that in some cases, random behavior by animals might be connected to foreshocks or the initial stage of an already underway quake. In fact, they found animal behavior coinciding with foreshocks on several occasions in the collected data.

"The animals may sense seismic waves — it could P (primary), S (secondary) or surface waves — generated by foreshocks," Woith suggested. "Another option could be secondary effects triggered by the foreshocks, like changes in groundwater or release of gases from the ground which might be sensed by the animals."

Still, to prove any of this, scientists need continuous, long-term data related to animals experiencing earthquakes, something that lacks at the moment. Woith and his team believe a long-term record could help them determine if earthquakes have any role to play in this behavior or if it is something totally different, like some other kind of environmental change or long-term effect on the health of the animal population.

The study titled “Review: Can Animals Predict Earthquakes?” was published in the journal GeoScienceWorld on April 17.