Bats seem to be born with exceptional ability – a very accurate sense of time, as new research shows.
From their first flight, the echolocating mammals appear to know somehow precisely how long it regularly takes for the sound waves of their calls to bounce off prey and then echo back, a new study shows.
The innate temporal reference for the regular speed of sound helps bats figure out distances in terms of time instead of units of space like other animals and us do.
For instance – a bird chirping at the cave entrance isn’t 10 meters ahead of a bat. Instead, the bat would perceive the bird as being a few seconds away.
Yossi Yovel, a zoologist and neuroscientist from the Tel Aviv University of Israel, said:
“This may sound like a semantic difference, but I think that it means that their spatial perception is fundamentally different than that of humans and other visual creatures, at least when they rely on sonar.”
We perceive our surroundings mainly via sight. However, bats “see” what’s around them with sound. Unfortunately, however, that system is also prone to fail at times, just like our sight can sometimes be deceiving.
In an experiment, researchers altered the typical speed of sound in air, and it turned out that a shift in the speed of sound impacts a bat’s ability to fly.
The experiment involved raising six newborn bat pups in normal atmospheric conditions, plus five newborn pups in helium-rich air, which provokes a significant increase in the speed of sound.
The two groups then had their echolocating abilities evaluated in their “home” environments, and the results were surprising – The pups that flew in helium-enriched air, also called the “Heliox pups”, showed very similar behaviour to the “air pups” – those who grew in normal atmospherical conditions.
However, as the Heliox pups calls returned to them sooner than usual, they were often tricked into landing earlier than expected.
When bats fly and land, they need very accurate coordination of calls and body movements.
As they are nearing the target, the echolocation frequency speeds up, and as it’s nearing the landing surface, the bat rolls its body and stretches out its legs to land safely.
The more curious aspect of the experiment came when the scientists repeated the experiment a few times. The Heliox pups kept trying to land with the regular speed of sound reference and never learned to adjust to the helium-rich environment. Trial and error didn’t do them justice, it seems.