Hey, they said "tech"...
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Published Thursday, Aug. 23, 2001, in the San Jose Mercury News


Technology clues from starfish
Unique lenses may help in computers, telecom

BY WILLIAM MCCALL
Associated Press 

Rows of tiny crystals that armor the skeleton of a certain kind of starfish
act as an array of microscopic lenses that would be difficult for even the
best engineer to duplicate, researchers say.

The high optical quality of the microlenses in the brittlestar could help
scientists design better computers or better telecommunications networks,
according to scientists at Lucent Technologies' Bell Labs in Murray Hill,
N.J.

They identified the lenses after marine biologists noted the brittlestar
appeared to be using the wrong kind of camouflage.

The creature would turn dark during the day, making it more visible to
predators, and would turn whitish gray at night, again making it more
noticeable.

``So it's just the opposite of what you expect to hide from predators,''
said Joanna Aizenberg, who led the study at Bell Labs.

Instead of trying to camouflage themselves, the brittlestars were using
their microlenses as a sophisticated system to sense light in order to
navigate and avoid predators.

The lens system turned the brittlestars lighter at night to increase their
sensitivity. During the day, they turned darker to cope with the brighter
light.

The shape of the crystals helped focus the light extremely precisely,
Aizenberg said.

``We were quite surprised to observe that not only do they focus light, but
the characteristics of these tiny lenses are far beyond anything we can
imagine currently manufacturing,'' she said.

The unique spherical shape of the microscopic lenses may have applications
for electronic and computer design, or it may help produce superior optics
that can adapt to changing conditions, she said.

Her study, which appears today in the journal Nature, noted the calcium
carbonate crystals -- or calcite -- also provide structural support for the
brittlestar skeleton.

The lens design could prove especially useful for optical computers --
machines that use changes in light to store data instead of movement of
electrons across a silicon wafer or circuit, according to another
researcher. Light comes in packets of energy called photons.

``At some point we'd like to have optical computers, but to get to that
point we have to move photons with the sophistication we now move electrons,
and we aren't able to do it yet,'' said Sonke Johnsen, a biologist at the
Woods Hole (Mass.) Oceanographic Institution.

Johnsen said the latest research on the brittlestar's light-sensing ability
helps explain why the creature can move so quickly to evade a threat, unlike
other forms of starfish.

``They are really active, clever and fast animals,'' Johnsen said. ``You'd
have to work hard underwater to catch one
Cam

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