Grasshoppers Change Their Tune to Stay Tuned Over Traffic Noise

A recent study shows that humans are not only responsible for climate change but also for animal behavior. A study done by Ulrike Lampe and colleagues from the University of Bielefeld, Germany, showed that the sound that grasshoppers made was affected by man-made sounds such as traffic on busy roads. Grasshoppers use the sounds to mark territory, find mates, warn off predators and other means of communication.

 Lampe collected 188 male bow-winged grasshoppers. Half of them from quite locations and the other half next to busy roads with loud traffic. They made the grasshoppers produce their sounds by exposing them to female grasshoppers. Close to 1000 recordings showed that the grasshoppers that lived near busy roads made different sounds. It was found that the grasshoppers raised the volume of the lower-frequency sounds since the traffic was making these lower-frequency sounds less audible.

This is important because traffic noise may be harmful to the grasshopper’s mating system. Lampe says that "Increased noise levels could affect grasshopper courtship in several ways. It could prevent females from hearing male courtship songs properly, prevent females from recognizing males of their own species, or impair females' ability to estimate how attractive a male is from his song."

I found this quiet shocking. I was unaware that humans had such a great impact on animal behavior. This should act as a wakeup call for us as humans and remind us that we are not the only species that belong to this planet.