SCIENCE: Squid skin reveals hidden messages

1 view

Skip to first unread message

EcoPolis

unread,

Sep 21, 2006, 5:46:12 AM9/21/06

to EcoPolis

=====================================================
Squid skin reveals hidden messages
=====================================================
MBL scientists find anatomical evidence for a hidden communication
channel that remains masked during camouflage

MBL, WOODS HOLE, MA -- In the animal world, squid are masters of
disguise. Pigmented skin cells enable them to camouflage
themselves--almost instantaneously--from predators. Squid also produce
polarized skin patterns by regulating the iridescence of their skin,
possibly creating a "hidden communication channel" visible only to
animals that are sensitive to polarized light.

In research published today in the journal Biology Letters, MBL (Marine
Biological Laboratory) researchers Lydia Mäthger and Roger Hanlon
present evidence that the polarized aspect of the skin of the longfin
inshore squid, Loligo pealeii, is maintained after passing through the
pigment cells responsible for camouflage.

While the notion that a few animals produce polarization signals and
use them in communication is not new, Mäthger and Hanlon's findings
present the first anatomical evidence for a "hidden communication
channel" that can remain masked by typical camouflage patterns. Their
results suggest that it might be possible for squid to send concealed
polarized signals to one other while staying camouflaged to fish or
mammalian predators, most of which do not have polarization vision.

Mäthger notes that these messages could contain information regarding
the whereabouts of other squid, for example. "Whether signals could
also contain information regarding the presence of predators (i.e., a
warning signal) is speculation, but it may be possible," she adds.

Mäthger and Hanlon maintain that the mechanism behind the transmission
of polarized light through squid pigment cells warrants further study.
Likewise, investigation of this masked polarization signaling system in
squid and other cephalopods in natural environments would provide
insight into animal camouflage mechanisms and may uncover similar
examples in other species.

###

The MBL is an international, independent, nonprofit institution
dedicated to improving the human condition through creative research
and education in the biological, biomedical and environmental sciences.
Founded in 1888 as the Marine Biological Laboratory, the MBL is the
oldest private marine laboratory in the Western Hemisphere. For more
information or to join the MBL Associates, visit www.MBL.edu.