A Saharan desert ant (Cataglyphis bicolor), relative of the Saharan silver ant, running along a sand dune. Image: © KingmaPhotos/Stock.adobe.com
An ant that lives in the intense heat of the Saharan desert has evolved to become the fastest of its kind ever recorded.
If there was ever to be an Olympics running event for ants, the Saharan silver ant (Cataglyphis bombycina) would easily win gold. Writing in the Journal of Experimental Biology, researchers from the University of Ulm in Germany clocked the ant with a running speed of 855mm per second, thanks to legs that can swing at speeds of up to 1,300mm per second.
“Even among desert ants, the silver ants are special,” said researcher Harald Wolf. Such speed is necessary for survival as its home in the blistering sun of the Saharan desert means staying too long in direct sunlight would lead to a quick death.
Its main source of food comes from scavenging corpses that have fallen victim to the intense heat, but little was known about how they can travel so fast across the sand. To determine this, the researchers eventually discovered a nest, connected an aluminium channel to the entrance and placed a feeder at the end to lure the ants out.
Once lured out with mealworms – a favourite food of the ant, according to the researchers – they would scurry back and forth in the channel, which had a camera mounted to it to track their speeds. A nest was also excavated and returned to Germany to record how they move at cooler temperatures.
Saharan silver ant workers in the desert at Douz, Tunisia. Image: Harald Wolf
A biological marvel
At speeds of 855mm per second, the ant strides an incredible 108 times its own body length per second at the hottest part of the day. However, this speed falls considerably at lower temperatures to just 57mm per second.
One of the few ants that comes close to the speed of the Saharan silver ant is the larger Cataglyphis fortis, which can hit speeds of 620mm per second. The new record holder’s speed now brings it closer to the top of the list of world record-breaking creatures, alongside Australian tiger beetles (which can run 171 body lengths per second) and California coastal mites (377 body lengths per second).
What makes the Saharan silver ant even more remarkable is that it can hit such speeds despite its limbs being 20pc smaller than its larger, leggier cousins. To find out how this was possible, the researchers showed it could achieve 47 strides per second with stride lengths quadrupling from 4.7mm to 20.8mm as the ant shifted up through the gears.
Also, rather than running, the ants switched to a gallop with all six feet lifting off the ground at speeds above 300mm per second. The researchers suggested that these speeds in such a small creature might mean its muscles are pushed to their physiological limit.
“These features may be related to the sand dune habitat,” said Wolf, adding, “[they] could prevent the animal’s feet from sinking too deeply into the soft sand.”
