Squid's colorful, changeable skin enables the animal--and their
close relatives, cuttlefish and octopus--to display
extraordinary camouflage, the speed and diversity of which is
unmatched in the animal kingdom. But how squid control their
skin's iridescence, or light-reflecting property, which is
responsible for the animal's sparkly rainbow of color, has been
unknown. In a new study, MBL (Marine Biological Laboratory)
researchers Paloma Gonzalez Bellido and Trevor Wardill and their
colleagues report that nerves in squid skin control the animal's
spectrum of shimmering hues--from red to blue--as well as their
speed of change. The work marks the first time neural control of
iridescence in an invertebrate species has been demonstrated.
Squid skin is extraordinary because it has two ways to produce
color and pattern. Pigmented organs called chromatophores create
patterns with yellow, red, and brown colors. Underneath the
pigments, iridophores, aggregations of iridescent cells in the
skin, reflect light and add bl