Scientists have discovered a species of dragonfly whose females will fake their own deaths. This is more than just playing dead.
The female common hawker dragonfly feigns death to escape aggressive male pursuers. Common hawkers come in droves to ponds in the Swiss Alps to breed. At these ponds, males greatly outnumber females. Male common hawkers attempt to mate several times in their lifespan, but unlike males of other dragonfly species, they don’t safeguard the eggs at all. Their energy is spent searching for another partner, whom they can grasp in mid-flight.
It’s clear why the female common hawkers evolved a diversion against their aggressive suitors. So how do these chases typically play out?
The biologist Rassim Khelifa was the first researcher to note this odd behavior in female common hawkers. One day around these ponds, Khelifa observed a male chase a female, when, suddenly, she plummeted to the ground and lay upside down, motionless. The male hovered for a moment, then left. But when Khelifa walked to the fallen dragonfly, she quickly flew away. So she must have been alert the whole time.
But she avoids the males because mating again decreases her chances of survival. In his observations of 31 chases, Khelifa recorded that 27 females feigned death. 21 successfully ditched the male pursuer. And this behavior is known to exist in only four other species in the world. That makes this female dragonfly’s stunt incredibly rare and something extraordinary.
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Sources
- National Geographic - Why Female Dragonflies Go To Extreme Lengths To Avoid Sex
- Phys Org - Female Dragonflies Found To Fake Death To Avoid Male Advances
- Newsweek - Female Dragonflies Fake Death To Avoid Males Harassing Them For Sex
Y: Don, scientists have discovered a species of dragonfly whose females will fake their own deaths.
D: Oh, Yaël, my dog does the same thing for a treat.
Y: I’m not talking about playing dead. The female common hawker dragonfly feigns death to escape aggressive male pursuers. Common hawkers come in droves to ponds in the Swiss Alps to breed. At these ponds, males greatly outnumber females. Male common hawkers attempt to mate several times in their lifespan, but unlike males of other dragonfly species, they don’t safeguard the eggs at all. Their energy is spent searching for another partner, whom they can grasp in mid-flight.
D: It’s clear why the female common hawkers evolved a diversion against their aggressive suitors. How do these chases typically play out?
Y: The biologist Rassim Khelifa was the first researcher to note this odd behavior in female common hawkers. One day around these ponds, Khelifa observed a male chase a female, when, suddenly, she plummeted to the ground and lay upside down, motionless. The male hovered for a moment, then left. But when Khelifa walked to the fallen dragonfly, she quickly flew away.
D: Then, she must have been alert the whole time!
Y: Exactly. But she avoids the males because mating again decreases her chances of survival. In his observations of 31 chases, Khelifa recorded that 27 females feigned death. 21 successfully ditched the male pursuer. And this behavior is known to exist in only four other species in the world. That makes this female dragonfly’s stunt incredibly rare and something extraordinary.