In an Indian village, a change in the behaviour of ants can mean more than it appears to.
Before heavy rain, people have long watched ants carry eggs and larvae towards higher, drier ground. Frogs become louder. Birds alter their movement. Snakes sometimes leave their hiding places.
Such observations have travelled through generations as folklore.
But there is a scientific question underneath them: are animals actually sensing changes before humans can?
The answer is more interesting than the idea of a “sixth sense”.
Animals do not predict earthquakes, cyclones or floods in the human sense. Instead, their bodies can detect physical signals that people cannot easily hear, feel or see, from vibrations travelling through the ground to changes in atmospheric pressure.
And that could explain why animals sometimes appear to move before disaster arrives.
When the ants move
Across many parts of India, ants are among the animals people closely observe before heavy rain. Their movement has been incorporated into traditional environmental knowledge in several communities.
The ants themselves do not know that a storm is coming.
Before heavy rain, people have long watched ants carry eggs and larvae towards higher, drier ground. Photograph: (Pavan R)
Their colonies, however, are buried in the environment.
Changes in soil moisture, humidity, temperature and water levels can alter conditions inside and around a nest. Moving eggs or larvae to safer ground may therefore be a response to environmental change rather than an act of prediction.
The earthquake question
The idea becomes more striking when the disaster is an earthquake.
For centuries, people have reported dogs barking, snakes emerging, birds taking flight and livestock becoming restless before earthquakes. India has its own body of stories around unusual animal behaviour, particularly across the seismically active Himalayas and Northeast.
There is a possible biological explanation.
An earthquake does not send just one kind of wave through the Earth. P-waves, or primary waves, travel faster than the more destructive S-waves that follow. Animals capable of detecting subtle ground vibrations may register these early movements before humans consciously feel the main shaking.
Elephants are particularly interesting because they can detect low-frequency vibrations through their feet and communicate using very low-frequency sounds. Snakes are also highly sensitive to vibrations travelling through the ground.
But this does not mean a snake can tell us an earthquake is coming tomorrow.
The US Geological Survey notes that unusual animal behaviour has been reported before earthquakes for centuries, but scientists have not established a consistent pattern that can reliably predict when an earthquake will occur.
An animal may detect a disturbance. It cannot necessarily tell us what caused it.
The 2004 tsunami
That distinction became important after one of the deadliest natural disasters of modern times.
On 26 December 2004, a magnitude 9.1 earthquake struck beneath the Indian Ocean off Indonesia, generating a tsunami that killed at least 225,000 people across countries around the Indian Ocean, according to the BBC.
Many coastal communities received no warning.
The US Geological Survey notes that unusual animal behaviour has been reported before earthquakes for centuries, but scientists have not established a consistent pattern that can reliably predict when an earthquake will occur. Photograph: (AFP)
In the minutes and hours before waves reached shore, however, eyewitness accounts described animals behaving differently. The BBC reported accounts of elephants moving towards higher ground, flamingos abandoning low-lying nesting areas and dogs refusing to go outdoors. In Thailand’s Bang Koey village, residents reportedly saw buffaloes suddenly turn towards the sea before running uphill shortly before the tsunami struck.
The stories became part of the mythology surrounding the disaster.
But scientists have repeatedly cautioned that such accounts cannot establish that animals predicted the tsunami.
What they do demonstrate is the possibility that animals responded to environmental signals associated with the earthquake, waves or changing conditions around them.
A weather radar of their own
The same principle applies to storms.
Many birds can detect changes in atmospheric pressure, while some animals hear frequencies far below the range of human hearing. These abilities can become useful when weather conditions begin changing.
Research has found that some birds respond to falling barometric pressure associated with approaching storms. Migratory birds can also respond to atmospheric conditions while navigating over long distances.
A falling pressure system that means “bad weather approaching” to a meteorologist may simply mean “conditions are changing” to a bird.
Folklore isn’t necessarily the opposite of science
This is where India’s traditional knowledge becomes worth examining carefully.
Some observations may have been shaped by folklore over generations.
Science does not have to accept every traditional interpretation to take the observation ser
The useful question is whether the behaviour can be measured, repeated and linked to a specific environmental change.
Could ants reliably indicate rising soil moisture before floods? Can birds’ movements reveal approaching atmospheric disturbances? Can animal responses to ground vibrations improve our understanding of earthquakes?
These are testable questions. Not prophets. Sensors.
An animal body is equipped with sensory systems shaped by millions of years of evolution. Vibrations, pressure, sound, humidity and other changes that barely register with humans can become information for another species.
But animal behaviour is not precise enough to replace scientific warning systems. A dog refusing to go outside could mean many things. Birds may move because of predators. Ants may relocate because their nest has become wet.
That uncertainty is exactly why researchers need controlled studies rather than anecdotes.
Still, the old observations raise a question modern technology has not made irrelevant.
