ABS Media Information

Copulatory dialogue: female spiders sing during copulation

Female signaling to the male during copulation has seldom been studied, but may be common in a variety of animals. Females of the spider Physocyclus globosus sing during copulation. Singing tends to occur when the male squeezes the female with his powerful genitalia (whose muscles are probably the strongest in his body); it apparently induces him to loosen this squeeze. When a female mated with two males, the male that responded more consistently to her singing by loosening was “rewarded” by fathering a greater proportion of her offspring. Greater numbers of squeezes also correlated with increased paternity. This is the first study to document apparent communication between male and female during copulation and show that it has reproductive consequences for the male. It thus opens a new field of inquiry regarding male-female sexual interactions, and confirms (once again) that females are more active in sexual interactions than previously appreciated.