The feathers of an African bird which allow it to hold and carry water at speeds of up to 40mph could provide the key to space-age water bottles which keep liquid still whilst we move.
Researchers used high-resolution microscopes to study the impressive feathers of the desert-dwelling sandgrouse close-up and decipher how they store water.
Male birds can store up to 15 percent of their body weight in water in feathers on their bellies – and travel up to 40mph over 20 miles back to their nest whilst hardly spilling a drop.
The fascinating bird has long been the subject of scientific interest due to this incredible water-carrying talent.
Now, American researchers are able to demonstrate how these feathers work.
The study authors hope the new discovery could lead to innovative new products including water bottles which hold water to prevent annoying sloshing around and netting which can collect and retain water from fog.
The collaborative research team, from both Johns Hopkins University in Baltimore, Maryland and the Massachusetts Institute of Technology (MIT) teamed up to study how the feathers of the desert-dwelling sandgrouse so successfully store water.
The bird inhabits stony, semi-desert environments in Africa and the Middle East and they typically nest around 20 miles from watering holes to stay safe from predators.
However, to transport water home to its thirsty chicks, adult males perform one of nature’s most impressive examples of water carrying.
Male sandgrouses gather water at watering holes and store it in the feathers on their bellies before transporting it back to their nests.
This feat is made even more impressive considering the sandgrouse is holding around 15 percent of its overall body weight in water and keeps most of it secured during its half-an-hour flight.
The male sandgrouses are the only birds known to hold onto water like this, and their specially-adapted belly feathers are the key to their rare talent.
Other researchers picked up on these extraordinarily useful feathers as long as five decades ago but, until now, it was not known how they function.
The Johns Hopkins and MIT team obtained the necessary feathers from a collection in the Harvard University Museum of Comparative Zoology.
The researchers honed in on the microstructure of the birds’ belly feathers using scanning electron microscopy, microcomputed tomography, light microscopy and 3D videography.
They looked in minute detail at the shafts – each just a fraction of the width of a human hair – as well as the even more minuscule individual barbules of the feathers.
The scientists greatly magnified the feathers and looked at them when both wet and dry.
Then, in a delicate but crucial move, they dunked the dry feathers in water whilst magnified, pulled them out and submerged them again – emulating a male sandgrouse at a watering hole.
Study co-author Jochen Mueller, an assistant professor at Johns Hopkins’ Department of Civil and Systems Engineering, said the team had to proceed with such fragility during the maneuver that they ‘couldn’t even breathe’ for fear of blowing the water off the feathers.
Mueller, who specializes in smart materials and design, described the individual feather structure as magnificent.
He explained how components in the feathers were optimized in several ways to hold and retain water, including the way they bend, how the barbules form protective, tent-like clusters when wet and how tubular structures within each barbule capture water.
The study, published today in the scientific journal The Royal Society Interface, also found that individual feathers held the water through a forest of barbules near the shaft, working together with the curled barbules near the tip acting almost like caps.
Mueller said: “It excited us to see that level of detail.
“This is what we need to understand in order to use those principles to create new materials.
“It’s super fascinating to see how nature managed to create structures so perfectly efficient to take in and hold water.
“From an engineering perspective, we think the findings could lead to new bio-inspired creations.”
The team additionally computationally modeled the water intake of the feathers and expects their findings to influence future engineering designs that require controlled absorption, secure retention and the easy release of liquids.
Amongst the exciting new engineering products the feathered could inspire are ‘next-level’ medical swabs, space-aged water bottles and nets which can collect and retain water from fog and dew in desert regions.
On his designs for futuristic water bottles or sports backpacks, Mueller explains these would safely hold plenty of liquid but have inner systems based on the sandgrouse’s feathers which would keep the liquid from swinging around whilst someone walks or runs with it.
Medical swabs would also become easier to use when you can efficiently soak up liquid but it’s much easier to release it.
This release issue proved problematic in collecting Covid-19 nasal test samples during the pandemic.
The team next plans to print similar structures in 3D and pursue commercial applications.
Produced in association with SWNS Talker
