Q: Why do katydids sing?
A: Katydids are green, they’re shaped like leaves, and they’re active at night — they’re basically invisible. That’s great for avoiding predators, but it makes it tough to find mates. Males sing so females can find them.
Q: What do their songs sound like?
A: Some katydids sound like a gushing faucet. Others sound like a sprinkler: pssst ... pssst ... pssst. Males make sound by rubbing their wings together.
Q: What do you hope to learn about katydids?
A: Lots of males sing at the same time. I want to know what signals go into a female’s brain to make her choose one male’s song instead of another’s.
Q: How can you tell what goes into a female’s brain?
A: Katydids hear the same way we do. Sound goes into their ears. It’s converted to electricity. The electricity travels through nerves to their brain. I put wires on katydids so I can graph the electrical signals as they move through their nerves.
Q: What does the graph look like?
A: We make lots of graphs, but one looks like squiggly lines. You can learn a lot from those squiggles, though.
Q: Like what?
A: I learned that with one kind of katydid, a female’s nerves filter out some signals before they ever reach her brain. These signals come from males who sing a fraction of a second after other males. But if the signal never reaches her brain, then she never actually “hears” the late singers. So, the late singers may not get many girlfriends.
Nichole LeClair Terrill