Female crickets choose mates by comparing male songs
Washington, Apr 22 : Female field crickets tend to remember attractive males on the basis of their songs, and then choose their mates accordingly, a new study has found.
In the research, UC Riverside biologists have found for the first time that female crickets compare the information about the attractiveness of available males around them with other incoming signals when selecting attractive males for mating.
Thus, the researchers suggested that social learning - the ability to learn information from other individuals of the same species - has deep impacts on insect behaviour and may act as a linchpin in evolution.
"Most people would never have imagined that insects could remember characteristics about other individuals around them," said Nathan W. Bailey, the first author of the research paper.
He added: "The vast majority of studies of insect learning focus on foraging behaviour, and in non-social insects - like field crickets - it is truly a surprise to find that they can change their behaviour based on remembered social information.
"Usually, we think of evolutionary pressure, or selection, as a force in the physical environment - like climate or food availability. But our research shows that the social environment animals experience is an important force, too. Social effects should therefore be given greater attention in models of evolution in species ranging from insects to humans."
In field crickets, males use song as a long-range signal to attract females for mating. The females, on the other hand, hear the males'' song before responding to a potential mate.
"We found that females that heard attractive males beforehand were less attracted to average males than females that heard unattractive males beforehand," said Bailey.
He added: "In non-social invertebrates the outcome of male ornament evolution may depend much more on the ability of females to remember information about social encounters than was previously thought.
"Our research shows that insects can learn about each other. They are a lot cleverer than we thought they were. In the past, people have thought of insects somewhat as mindless automatons that just follow certain decision rules. But it is becoming increasingly clear that they have complex cognitive capacities that play an important role."
The researchers performed the research in the lab using hundreds of field crickets.
For the study, they exposed all females to an ''average'' male song, and assessed the females'' responses to it.
If the females responded, the researchers concluded that the females found the song attractive.
Then they manipulated a different set of females'' experience beforehand, with some having heard attractive songs, and some having heard unattractive songs
It was found that those females that heard unattractive songs responded more strongly to the ''average'' male than those females that heard the attractive song.
Thus, the researchers concluded that prior experience affected perception of attractiveness among female field crickets.
The results of the study appeared in the latest online issue of the Royal Society journal Biology Letters. (ANI)