Frogs inspire antifreeze surface, according to a report in ScienceDaily 24 November 2014 and American Physical Society meeting abstracts 23 November 2014. When ice accumulates on aircraft wings it can increase the weight of the wings and decrease lift, making take-off and landing more hazardous. Spraying the wings with antifreeze helps prevent ice build-up, but using large amounts of it can be corrosive, and is a pollution problem. Chemical engineers have experimented with water repelling surface coatings, which are effective in preventing ice build up during freezing rain, but do not prevent ice accumulation from frost or rime, where the ice forms from water vapour.
Three scientists from Arizona State University have now developed a double-layered antifreeze coating they claim was “inspired by functional liquid secretion in natural systems”. One of the researchers, Konrad Rykaczewski, saw poison dart frogs during a visit to Panama and learned that when threatened, the frogs secrete a toxic substance onto the surface of their skin. The substance is made and stored in glands under the epidermis, the outermost layer of skin.
Rykaczewski explained: “This was exactly the functionality that we wanted from the anti-icing surfaces: we wanted to secrete antifreeze only in response to the presence of ice on the surface, irrelevant of form – frost, glaze or rime”.
The Arizona team’s antifreeze coating consists of a porous outer layer of superhydrophic (highly water repelling) material over an inner layer saturated with anti-freeze. The outer layer repels freezing rain, but if ice accumulates the antifreeze flows out through the porous layer and melts the ice. This system uses the antifreeze much more efficiently, as it is only released when it is needed. Rykaczewski’s team are now working on getting the system to work more efficiently, as well as finding ways to use it on a large scale.
Editorial Comment: The ability to sense a need, plus have a solution ready to meet that need, as well as applying the solution when necessary, is one of the features that distinguishes all living things from non-living matter. Our own skin also contains glands that manufacture and store substances needed to maintain the surface properties of our skin, and these glands respond to signals from the rest of the body and in response deliver substances such as oil and sweat to the skin surface. However, as the Arizona scientists demonstrate, such systems only work if there is plan and purpose, involving an understanding of the problem, an understanding of the properties of materials, and creative design to manipulate the materials to meet the need.
All of this requires an intelligent being outside the system to get it to work. If Rykaczewski’s team are able to develop their surface coating to work on a large scale it will require even more creative design and engineering than has already been applied to the iced-wing problem. Leaving it to chance random processes will only degrade it. Therefore, when anyone claims that frog skin evolved by chance, but take the credit for designing an ice resistant wing surface based on the surface properties of the frog, they are without excuse in the eyes of the Original Frog Creator. (Ref. herpetology, design, engineering)
Evidence News vol 14, No. 21
10 December 2014
Creation Research Australia