Scientists looking for new ways to harvest moisture from the atmosphere have once again found inspiration from the lowly Namib desert beetle.
The dime-sized insect is native to Southern Africa, one of the most arid regions in the world, and is remarkable for its ability to collect water from early morning fogs using only the bumps on its back. You can see a brief example of this amazing bit of natural engineering below.
So how exactly do these bumps make the desert beetle such an efficient harvester of moisture? Whereas previous studies focused on the chemistry of its back as the foundation for its success, researchers from Harvard University now believe it has something more to do with the bumps' unique geometry. By replicating the topography of the bumps (with some millimetres across), they were able to make water drops grow an astounding six times faster than normal.
But they didn't stop there. To help speed up the collection of the drops rolling off the bumps, the researchers incorporated designs from cactus spines and lubrication from the slippery death trap of a carnivorous pitcher plant. This "Frankenstein-esque" material is yet another amazing example of how biomimicry can change the world.
"By optimizing that bump shape through detailed theoretical modeling and combining it with the asymmetry of cactus spines and the nearly friction-free coatings of pitcher plants, we were able to design a material that can collect and transport a greater volume of water in a short time compared to other surfaces," study lead Kyoo-Chul Park said in a statement.
You can view the new collection method in action in the video below.
Besides greatly assisting communities in arid regions with water harvesting, this new material could also help industries utilizing heat exchange, dehumidification and desalination.
"Thermal power plants, for example, rely on condensers to quickly convert steam to liquid water," said Philseok Kim, co-author of the paper "This design could help speed up that process and even allow for operation at a higher temperature, significantly improving the overall energy efficiency."