Nanotech colours inspired by bird feathers, according to ScienceDaily 13 May 2015 and ACS Nano doi:10.1021/acsnano.5b01298. The brilliant colours of bird feathers has long been known to be the result of structural colour, and not just coloured pigments in the feathers. But how can you copy that? Structural colour is produced by the way microscopic structures reflect and refract light. This gives intense, and often iridescent colours in pure hues. Some birds get structural colour in their feathers from the way melanosomes, tiny packages of melanin, are organised in the feathers.
Nathan Gianneschi, a professor of chemistry and biochemistry at the University of California, San Diego, and colleagues were “directly inspired by the extensive use of self-assembled melanosomes to produce colours in avian feathers” and set out to produce structural colour using the same principles. The team used a similar molecule to melanin named dopamine, which they linked together to form meshes called polydopamine. The polydopamine formed tiny, almost uniformly sized spheres, which the scientists then formed into thin films of tightly packed particles. Depending on the concentration of particles and thickness of the films the researchers produced intense pure colours in red, orange, yellow and green.
Nathan Gianneschi summarised the research: “We synthesized and assembled nanoparticles of a synthetic version of melanin to mimic the natural structures found in bird feathers. We want to understand how nature uses materials like this, then to develop function that goes beyond what is possible in nature”.
Matthew Shawkey of University of Akron, another of the research team commented: “What has kept me fascinated for 15 years is the idea that one can generate colours across the rainbow through slight (nanometer scale) changes in structure”. He went on to say that biomimicry, the study and copying of living structures, can be used to solve practical problems. For example, the polydopamine, like melanin absorbs UV light, structural colours do not fade like pigments, and pure hues are useful in colorimetric sensors.
Editorial Comment: Biomimicry is best defined as “God made it best, we copy it next”, and it is the ultimate evidence that it takes creative design and intelligence to make living things work. Biomimicry involves using our intelligence to study living things, and understand how they work, and then further using our intelligence to creatively design and make substances and structures that will have similar functions to the ones we studied in living organisms.
In spite of Gianneschi’s optimism, any results we do get are usually less effective than the structures and functions observed in living organisms. We know from trial and error copying, that chance random processes are completely useless in getting any results. Precise detailed intelligent copying does the trick. Therefore, any scientists making use of biomimicry are truly without excuse for failing to honour the God of Creation.
The bright colours of bird feathers always remind this editor of that classic hymn “All Things Bright and Beautiful”. Like much that came out of Victorian England the hymn is over-sentimental, but the last verse is true and challenging: “He gave us eyes to see them, And lips that we might tell How great is God Almighty, Who has made all things well.” For a less sentimental expression of the same thoughts see Romans 1:18-25. (Ref. ornithology, colours, nanotechnology)
Evidence News vol. 15, No. 8
20 May 2015
Creation Research Australia