New type of vision found in shrimp

The common mantis shrimp sees light in a way that is vastly different to other animals, including us humans - and its probably all about sex
April 3, 2008

New type of vision found in shrimp



Professor Marshall and a mantis shrimp

University of Queensland research has

identified a completely new type of vision

never seen before in the animal world –

and it is probably all about sex

Professor Justin Marshall, from UQ's School of Biomedical Sciences and the Queensland Brain Institute, has found the common mantis shrimp sees light in a way that is vastly different to other animals, including us humans.

“We are sensitive to light intensity and color, but we need cameras and filters to allow us to see different types of light,” Professor Marshall said.

“To find out these animals can see circular polarized light, it is as if we had discovered colour vision for the first time – it is quite a breakthrough.”

What puzzled Professor Marshall after discovering this unique talent in the mantis shrimp, was what it was used for?

“It really is bizarre why these animals even bother with this type of vision,” he said.

“But after doing a number of tests over the years looking at the physiology and behaviour of mantis shrimps, we have come to the conclusion it is used for sex.

“Only the males have this ability, implying it has something to do with sex.

“It is probably some secret communication channel between males and females while at the same time preventing predators from knowing what was going on.”

He said the mantis shrimp was an amazing animal to study as it has a very small brain but one of the world's most complex visual systems.

“Us humans only have three color channels,” he said.

“These little guys have 12, and can see both linear and circular polarized light – it is remarkable.”

He said humans could see the effect of linear polarization through things such as polarized sunglasses, which cut out glare for driving and boating.

Circular polarization is also used by humans in things such as 3D glasses for movies, filters for cameras and medical imaging systems to detect skin cancer.

“It's quite amazing to think how much circular polarization technology we have, and that 400 million years ago nature got there first with a mantis shrimp's eyes,” he said.

The research is published in the current edition of scientific journal Current Biology.