Could a desert beetle be the key to pulling water from the air?

Residents of the world’s most arid regions might someday raise a glass of water to the Namib desert beetle, which is giving up secrets to harvesting water from the air.

Several species of Namib desert beetles are native to an area of southwestern Africa without much ground water and rainfall averages of about 1.3 to 5 centimeters a year. To compensate, the beetles  “fog bask,” leaning into the fog that rolls in several times a week to collect the water they need to stay alive. Water from the air collects on the beetles’ abdomens, then rolls into their mouths.

Researchers have studied the beetles for decades, but several teams have peeled back more of their mysteries in recent years.

The desert beetle inspired researchers, who found that bumpy surfaces caught water droplets with more efficiency than did a smooth sphere. IMAGE: Anas Albounni, KUST Review

Hunter King, a physicist at the University of Akron in Ohio, USA, and his team took their cues from the bumps on the beetle’s back and found that shape and texture could become a “fog magnet,” with 1-millimeter bumps catching water with 2.5 times more efficiency than a smooth sphere with the same surface area.

“We think the real take-away message is one of enhanced filtration of hard-to-catch, low inertia particles/droplets,” King says.

In 2021, researchers from Fuzhou and Soochow universities in China and Nanyang Technological University in Singapore reported on how they mimicked the beetle’s exoskeleton, weaving superhydrophilic and superhydrophobic materials with copper particles to increase the water-harvesting rate of conventional fog harvesters. The researchers say their biomimetic material would be well-suited to large-scale production.