Cricket, Katydid Songs Are Best Clues to Species' Identities

September 5, 2006

In a nighttime chorus of insects, the easiest way to identify individual katydid and cricket species is by listening to their songs, according to one of the world's leading authorities on the jumping insects.

"Without sound, we'd be in a pickle," said Thomas Walker, an entomologist at the University of Florida in Gainesville.

Relying on morphology—body shape, structure, and color—to identify some katydids and crickets is next to impossible, he says.

"With DNA and so forth, we can. But for some species there's no way to identify them on the pin," he said, referring to insects held on display boards with special pins.

Crickets and katydids are closely related insects that all have big hind legs for jumping, long antennae, ears on their front legs, and wings that fold like a fan.

Trained scientists can tell the difference between the two types of insects, because crickets have three segmented feet while katydids have four.

But even for experts, just looking at the creatures doesn't easily reveal when two distinct species are side by side.

For example, the sand field cricket (Gryllus firmus) and the southeastern field cricket (Gryllus rubens) look nearly identical and inhabit the same geographical areas.

To tell them apart, Walker relies on his ears.

The sand field cricket chirps (listen here), whereas the southeastern field cricket trills (listen here).

"A three-year-old can tell the difference," Walker said.

Sound ID

Continued on Next Page >>




NEWS FEEDS     After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed.   After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed.

Get our news delivered directly to your desktop—free.
How to Use XML or RSS

National Geographic Daily News To-Go

Listen to your favorite National Geographic news daily, anytime, anywhere from your mobile phone. No wires or syncing. Download Stitcher free today.
Click here to get 12 months of National Geographic Magazine for $15.