In the wings of the butterflies there is a nanostructure that is extremely similar to the famous Vantablack.

Black butterfly wings are not just black material, but a complex structure for light absorption that can be compared to Vantablack, a material made of nanotubes with record low incident light reflection. This conclusion was reached by researchers from Duke University (USA), who were able to measure the parameters of scales on the wings of these insects. They are arranged much more complex than an array of nanotubes, but inexplicably thinner than it several times.

While Vantablack's official incident light absorption coefficient is 99.96%, butterfly wing scales are only two hundredths of a percent lower - 99.94%. Visually, both look like absolute blackness, a hole in space. But if Vantablack was created by humans, the butterfly wings are the result of evolution. However, scientists still have no idea what they need this radical black color for.

With a thickness of only 3-4 nanometers (20% of the thickness of the synthetic material Vantablack), the scales of the wings were very difficult to arrange. There are ridges, ledges, cells, honeycomb-like areas, like sponges, etc. It has been established that the darkest areas are fragments either with a ribbed surface or with thick legs at the base of the honeycomb. The same areas, which do not have such relief elements, reflect 16 times more light. Therefore, they are dark brown rather than black.

In general, the unprecedented level of light absorption in this bioconstruction is achieved by surface roughness and a huge absorption area.  In addition, given the number of butterflies with black wing color in the world, there is a chance that reproducing such a structure would be easier and cheaper than creating new Vantablack variations. And then the world will have the widest range of applications for it.

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