Natures wonders: crystal eyes (Introduction)

by David Turell , Friday, January 24, 2014, 20:39 (3954 days ago) @ David Turell

The brittlestar is one big eye. How does it form these crystals or are they formed naturally? It runs its arms with a nervous system but no central 'brain':-"On the top of the brittlestar's arms, are calcite domes about one-twentieth of a millimetre across. These focus light, avoiding the blurring that perfectly spherical lenses produce. The intricate calcite crystals are aligned so as not to split light into multiple images.-"The tiny crystal balls "were too similar to lenses to have been formed by chance", says Joanna Aizenberg, of Bell Laboratories and Lucent Technologies, Murray Hill, New Jersey. She happened upon the "incredible structures" while studying the brittlestar Ophiocoma wendtii1.-"It's astonishing that this organic creature can manipulate inorganic matter with such precision - and yet it's got no brain," says Roy Sambles, who works on optics and photonics at the University of Exeter in Britain.-"The crystals' growth must be self-organized - emerging from the right chemical environment rather than being engineered by detailed top-down control. "It's starting with a soup of chemicals and pulling out this wonderful microstructure," says Sambles, who fantasizes about emulating the process "in a bucket in a corner of the lab"."-http://www.nature.com/news/2001/010823/full/news010823-11.html