CANBERRA, Jan. 18 (Xinhua) -- Female fiddler crabs are more likely to pair with males that perform faster mating dances, an Australian study has found.
Researchers from the Australian National University (ANU) used robotic crabs to perform the fiddler crab at different speeds to determine if females were more likely to choose males that performed the dance faster or slower.
Female crabs used were from the East Point Reserve near Darwin in the Northern Territory. They were gathered and put in an enclosure with two robotic crabs performing a mating dance at different speeds.
Sophie Mowles, lead author of the study, said that the females "significantly preferred" the escalating robotic crab over the de-escalating alternative.
"It's a case of the faster, the more attractive," Mowles told Xinhua on Thursday.
"There doesn't seem to be a threshold rate above which the females prefer.
"They seem to assess the current speeds, along with changes in rate and prefer males that speed up their signal rate."
Researchers believe that females have a greater attraction to the males that perform faster because it exhibits that they have better stamina and greater physical fitness.
"By paying attention to signal rate, and changes in rate, females can select physically fit males that are not becoming fatigued," Mowles said.
"They may have 'good genes' for performance, which the female should want for her offspring as these may confer the ability to evade predators, maintain territories, display well themselves, or disperse or be in better health than males that slow down.
"This is likely not just true of the fiddler crabs, but for many other species that perform both simple and elaborate courtship displays."
For the most part, the females caught on that they were being courted by robots but some went along with it.
"The robots are mounted on a small base-plate, so once the females approached and touched this, most of them realized something wasn't quite right," Mowles said.
"Some did however 'tickle' the male with their legs as if he were real."
