Imma Perfetto
Cosmos science journalist
Biologists have studied an extreme gymnast of the animal kingdom, watching as it moves so quickly it appears to all but vanish.
The globular springtail (Dicyrtomina minuta) is a small but mighty bug that can backflip more than 60 times higher and 100 times longer than its own body length.
This tiny bug grows to only a couple of millimetres and can’t sting, bite, or fly its way out of danger. Instead, its preferred method of avoiding predators is to flip out so forcefully it seems to disappear!
“It only takes a globular springtail one thousandth of a second to backflip off the ground, and they can reach a peak rate of 368 rotations per second,” says Adrian Smith of North Carolina State University and the North Carolina Museum of Natural Sciences, USA.
“They accelerate their bodies into a jump at about the same rate as a flea, but on top of that they spin. No other animal on earth does a backflip faster than a globular springtail.”
Smith recruited participants to the study, which is published in Integrative Organismal Biology, by sifting through the leaf litter at the bottom of his own garden.
He sent them careening through the air by shining a light at them or lightly prodding them with a paintbrush.
This is where the low-tech portion of the study ends, however.
“Globular springtails jump so fast that you can’t see it in real time,” Smith says.
“If you try to film the jump with a regular camera, the springtail will appear in one frame, then vanish. When you look at the picture closely, you can see faint vapor trail curlicues left behind where it flipped through the one frame.”
Instead, he captured its Olympic-level gymnastics with high-speed cameras that capture 40,000 frames per second.
Slow-motion video reveals that a globular springtail doesn’t use its legs to manage this incredible feat.
Instead, it’s all thanks to its furca – an appendage that folds up under its abdomen and has a tiny, forked structure at its tip. The furca flips down and the forked tip pushes against the ground, launching the bug into a series of backflips.
“They can lean into a jump and go slightly sideways, but when launching from a flat surface, they mostly travel up and backward, never forward,” adds Jacob Harrison, a postdoctoral researcher at the Georgia Institute of Technology, USA, and co-author of the paper.
“Their inability to jump forward was an indication to us that jumping is primarily a means to escape danger, rather than a form of general locomotion.”
It’s clearly a high degree of difficulty, but do they stick the landing?
Apparently, globular springtails are just as likely to tumble to an uncontrolled stop as they are to grapple a surface, pushing out a sticky forked tube from their bodies to halt their momentum.
“This is the first time anyone has done a complete description of the globular springtail’s jumping performance measures, and what they do is almost impossibly spectacular,” Smith says.
“This is a great example of how we can find incredible, and largely undescribed, organisms living all around us.”
