Males who succeeded in snaring a mate were those that put in the most effort and paid the female a lot of attention, according to the study published today in Royal Society Proceedings B.
The study confirmed for the first time that strong sexual selection by females has played a role in the evolution of ornamentation and complex signalling among some male species.
Dr Michael Kasumovic, at the University of New South Wales, said biologists had spent decades investigating how female preference drives the development of ostentatious traits in males.
At its most extreme these traits can include intricate dances, bright coloration and songs such as in birds of paradise.
"It was always assumed that in general these traits do exist because of female preference," Dr Kasumovic said.
However to date there had been little empirical evidence to support this theory.
He said the research team — which was led by Madeline Girard and included Dr Damian Elias, at the University of California, Berkeley — aimed to fill this gap by focusing on the peacock spider, Maratus volans, because its suite of traits rivaled that of the bird of paradise.
The tiny jumping peacock spider — which measures just three to five millimeters — is endemic to Australia. The male is known for an abdomen flap that is intensely coloured and like the peacock lifts up and fans out during courtship.
They also perform an intricate ritual that includes vigorous leg waving and also generate a vibrating beat.
For the study, Ms Girard collected 120 spiders from the wild and allowed them to court in a natural environment within the laboratory.
The team filmed the courtship using high-definition cameras and used a laser vibrometer to measure the vibrations created by the male spider.
Dr Kasumovic said during 64 mating trials with virgin females, only 16 males were successful.
In 22 trials with mated females, none of the females re-mated.
He said the success by the males was dependent on "how vigorously a male dances and how much attention he pays to his mate".
The fact the mated females would not re-mate suggested they became more selective, Dr Kasumovic said.
His advice to the male peacock spider: "Try your best the first time, as once a female is mated, she gets pickier."
Dr Kasumovic said the female — which will attack and kill the male if she is not happy — did give warnings that the male should try harder.
This involved her wiggling or waving her abdomen, which resulted in the male either backing off or trying harder.
Read more at Discovery News
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