By Jennifer Carpenter, BBC News

媒體英語會帶大家一起學習 BBC 撰稿人在報道世界大事時常用到的單詞和短語。

Background: 招潮蟹在英語里被稱為 fiddle crab. 這是因為它們擁有一只特別大的螯，就像小提琴一樣。現在科學家們采用了一個機械螃蟹來說明雌蟹喜歡那些能夠以最大舞蹈動作來顯佩自己的雄蟹。

To the fiddler crabs, the Australian mudflats in the north of the country are a heaving dance floor, where a male must rely on his moves to attract a mate.

Male crabs attract passing females by waving their large yellow claws. If a female fancies a male, she will disappear down his burrow in the sand, and if she likes the hole as much as she likes the wave, she'll stay and mate.

But how do females choose between all of these waving suitors? Now a team from the Australian National University in Canberra have worked out what female crabs are looking for in a mate.

Sat beneath the unforgiving Australian sun, the researchers set up three fully adjustable robotic arms, that they are calling the Robocrab. Robocrab allows the researchers to vary the speed of the waves and the size of the claws.

The team showed that females prefer males with larger claws, and more vigorous waves, especially if the male is flankedby two less athletic wavers.

It seems, for the fiddler crabs at least, it pays to beef up, but hang outwithweedy friends.