NEW DELHI:

know when an

is about to strike, researchers have discovered. Their behavior changes significantly prior to the quake and they resume normal functioning only a day after it.

Gabriele Berberich of the

in Germany presented these findings on Thursday at the

annual meeting in Vienna according to

.

Berberich and her colleagues discovered that red wood ants preferred to build their colonies right along active faults in Germany. They counted 15,000 ant mounds lining the faults. These faults are fractures where the Earth violently ruptures in earthquakes.

Using a special camera mounted software that tracked changes in activity, Berberich and her colleagues tracked the ants round the clock for three years, 2009 to 2012. They found that the ants' behavior changed only when the quake was over magnitude 2. There were 10 earthquakes between magnitude 2.0 and 3.2 during this period, and many smaller ones. Humans can also sense quakes of over magnitude 2 only.

According to Berberich, normal ant activity consists of going about collecting food etc. during the day and resting in the night. But before an earthquake, the ants did not retreat into their mound in the night and bustled around outside it. This strange and abnormal behavior continued till a day after the earthquake, Berberich told a news conference, according to LiveScience.

How do ants know an earthquake is coming? Berberich suggested that they could either be picking up changing gas emissions or noting tiny changes in the Earth's magnetic field. Red wood ants have special cells called chemoreceptors which can detect changes in carbon dioxide levels. They also have magnetoreceptor cells for detecting electromagnetic fields, she said.

Berberich and her colleagues are planning to continue the research in areas where there are more and bigger earthquakes.

This is the first time ants' capability to react to future earthquakes has been reported. Earlier research had established another bizarre capability of some ants - the ability to withstand high radioactivity.

Earthquake sensitivity among animals and birds has been widely reported from across the world but in no case is it so much in advance and so predictable.