9 September 2011
Scientists have used a robotic crab to show that female fiddler crabs prefer males who can wave off the competition.
Click to hear the report:
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 flanked by two less athletic wavers.
It seems, for the fiddler crabs at least, it pays to beef up, but hang out with weedy friends.
Jennifer Carpenter, BBC News
Click to hear the vocabulary:
best dancing movements
- a mate
finds attractive (informal)
potential partners (an old-fashioned term)
strong and energetic
- to beef up
to become big and strong
- hang out with
spend leisure time with