When launched upside down, dragonflies flip 180 degrees quickly, changing the angle of their wings – but only if they can see their surroundings.
May 12, 2022
Dragonflies use a combination of visual cues and precise control of the tilt of their wings to perform aerial acrobatics.
The four-winged insects can quickly get up from the upside down position, but so far researchers have not been sure how they performed the feat. Jane Wang, who studies the physics of living organisms at Cornell University in New York, first noticed the intriguing behavior nearly eight years ago. To her surprise, when she released a dragonfly with its head forward, the insect turned faster than her eyes could see.
So Wang and her colleagues designed a series of experiments to find out exactly how insects handle this. First they drew white dots on the wings and bodies of seven dragonflies. They then released the insects upside down and recorded their movements with a high-speed video camera. They slowed down the frames to better see the exact angles of the wings and used a computer algorithm to create a three-dimensional model of dragonflies in motion.
The digital simulation revealed what Wang’s eyes could not see: dragonflies tilting their right and left wings at different angles to turn in just 200 milliseconds.
“When [dragonflies] they usually beat their wings, they constantly change their height, ”says Wang. “Now, on top of that, they have to make a difference between the left and the right wing – just a little bit.”
Some dragonflies rolled to the right, others to the left. But in all cases, the insects used a similar asymmetrical wing angle to turn in the air.
The experiment revealed the physical mechanism of lightning rotation of dragonflies, but did not answer how they felt upside down. Based on previous research, Wang said she suspected she might be using visual information from her large eyes with multiple lenses or from light-sensitive organs called survivors on top of her head.
The team then blocked the eyes and eyes of the dragonflies with opaque black paint and released the insects upside down again. This time they could not recover. “Sometimes they didn’t flutter their wings at all,” Wang said.
The researchers concluded that visual cues should help insects orient themselves in space, which then causes specific wing movement. Wang suspects that dragonflies are not the only ones using this two-piece technique.
“I think almost all flying insects have that ability because it’s a necessity,” she said. “Dragonflies are one of the most ancient insects. If they have already developed it, I suspect that modern ones have a similar ability. “
Reference journal: science, DOI:
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