澳大利亞的雄性華麗細尾鷦鷯總是在捕食者的警告叫聲后發出回應叫聲，而雌性鷦鷯則對這種接連發出的聲音特別敏感。CG報道。

It’s one of the oldest moves in teen dating. Head to a scary movie. As soon as the scary music kick in, your date cuddles closer for comfort. Well, some birds may have the same idea. Splendid fairy-wrens are small, sexually promiscuous birds native to Australia. It turns out that males get the attention of potential mates by making their move after a predator announces its presence. The research was published in the journal Behavioral Ecology. [Emma Greig and Stephen Pruett-Jones, "Danger may enhance communication: predator calls alert females to male displays"]

[Bird sound] That’s the sound of butcher-birds, which prey on splendid wrens. Every time male wrens hear that cry, they sing this in response [wren sound]. Researchers say the calls become layered atop one another, almost like a duet.

The scientists tested the response of female wrens by playing recorded bird calls. They played just the male fairy-wren call. Then they played the trill of the wrens singing immediately after the butcher-birds. The females became significantly more alert—looking to the sound or singing in response—after hearing the two calls together than they did if they heard just the wren. And so for both teens and wrens, a bit of fear might help a guy get the chick.

—Cynthia Graber