A team of researchers from the University of Zurich discovered an odd behavior among a species of dragonflies. Females that belong to the common hawker species (Aeshna juncea) play dead in front of males to avoid sexual harassment.
Researchers developed a study on the subject, and it can be found online in the journal Ecology. Initially, the study was supposed to look at the effect of temperature changes on the larvae. While he was observing them, zoologist Rassim Khelifa saw something peculiar.
- Female Aeshna juncea pretend to be dead to escape forceful mating.
- They avoid the males, since they leave them unsupervised after they lay their eggs.
- This is the only dragonfly species to display such a behavior.
Two dragonflies were chasing each other but, suddenly, one of them fell to the ground. The other one flew above it for a few seconds and then disappeared. Khelifa found this interesting and, when he looked closely, he discovered that the specimen which crashed on the ground was a female, while the chaser was a male.
At first, the zoologist thought that the female dragonfly was dead. However, the insect flew away when he came closer. Thus, the researcher suspected that this might be a trick. More precisely, the insect could have been avoiding being forced into mating.
Khelifa discovered that many female Aeshna juncea resort to such a behavior, so he decided to start looking at how they reproduce. Thus, he found that males usually lurk females and force them to mate. Then, they no longer guard them when they lay eggs.
This behavior is unique among dragonflies, as other species do not force their females to mate and remain close to them even after they lay eggs. Thus, female Aeshna juncea started engaging in this protective technique.
However, playing dead is not always successful. Around 77.7 percent of female dragonflies succeed in escaping from the prying males. This invasive behavior is interesting to analyze, as it is unheard of in other dragonfly species.
Image Source: Wikimedia Commons