Crickets that live near highways change their tune to overcome roadside noise, a new study reports.
Male bow-winged grasshoppers produce their song, which serves as a mating call, by rubbing a toothed file on their hind legs against a protruding vein on their front wings. These songs are produced with low- and high-frequency components.
Grasshoppers living in noisy environments had higher-frequency components in the low-frequency portion of their songs, said Ulrike Lampe, an evolutionary biologist at the University of Bielefeld in Germany and one of the study's authors. This makes sense because road noises can mask the grasshoppers' signals at the lower frequency, Ms. Lampe said.
She and her colleagues studied the crickets in a laboratory environment and exposed males to females to encourage them to sing. They recorded more than 1,000 songs and found that even in a quiet laboratory setting, males collected from roadside habitats produced significantly different songs.
"So we are relatively sure that this is a long-term effect," said Ms. Lampe. "It could be a genetic difference, or it may occur during larvae development."
Although the crickets are not an endangered species and seem well adapted to the sounds of traffic, noise caused by humans may be affecting other insects in negative ways, Ms. Lampe said. Such noise has previously been shown to affect the acoustic communication of birds, frogs and mammals.
The study appears in the journal Functional Ecology.
This article originally appeared in The New York Times.