This is scientific American's 60 second science.

I'm Christopher Intagiyata.

In the frog world, romance is often accompanied by a song.

It's the norm.

The vast majority of frogs have males calling to attract females.

Sandra Goot is an evolutionary biologist and herpetologist at the University of Campinas in Brazil.

And she studies frogs called pumpkin toadlets from the

cloud forests of coastal Brazil. They are extremely cool. They're teeny

tini-tini. They're neon orange and they wave their arms around when they feel threatened by either a predator or herpetologist and true to frog form they make this low call that sounds like a cricket like ch ch ch ch ch ch ch ch ch ch ch ch ch ch ch ch ch part. It appears the pumpkin toadlets are not able to hear the sounds they make.

Goot and her colleagues played recordings of the calls to the frogs to look for reactions.

The researchers also traced electrical impulses from the frog's ears to their brains and even

dissected the frog's inner ear.

And it turns out, the frogs just don't have the equipment to hear their own voices.

The studies in the journal Scientific Reports.

Why would they call if they cannot hear their own calls, right?

Goote does have a few theories.

Perhaps she says the bulging throat movement associated with calling is a sexual signal

itself with the sound and inadvertent accompaniment.

Perhaps the frogs lost the ability to hear the calls at some point in their

evolutionary history when the displays did the job well enough on their own.

After all, they are a highly visual species. They're out during the day, brightly

colored, do the hand-waving thing.

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