Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cuttlefish Masters of Disguise Despite Colorblindness

20.04.2006
Cuttlefish are wizards of camouflage. Adept at blending in with their surroundings, cuttlefish are known to have a diverse range of body patterns and can switch between them almost instantaneously. New research from MBL Marine Resources scientists, to appear in the May 2006 issue of the journal Vision Research, confirms that while these masters of disguise change their appearance based on visual cues, they do so while being completely colorblind.

While previous research has reported cuttlefish colorblindness, MBL Research Associate Lydia Mäthger and her colleagues in Roger Hanlon’s laboratory approached the problem in more depth and with a new behavioral assay. The researchers tested cuttlefish (Sepia officinalis) color perception through observing the animal’s behavioral response to a series of checkerboard patterned substrates of various colors and brightnesses.


Cuttlefish are wizards of camouflage. Adept at blending in with their surroundings, cuttlefish are known to have a diverse range of body patterns and can switch between them almost instantaneously.


Mäthger and her colleagues tested cuttlefish color perception through observing the animal’s behavioral response to a series of checkerboard patterned substrates of various colors and brightnesses. This series of images shows that cuttlefish exhibit the same disruptive pattern when they sit on a high contrast black and white or black and green checkerboard, but when on a low contrast (to their eyes) grey and green background, their body pattern remains uniform, suggesting that they can’t tell the two shades apart.

They found that the animals did not respond to the checkerboard pattern when placed on substrates whose color intensities were matched to the Sepia visual system, suggesting that these checkerboards appeared to their eyes as uniform backgrounds. However, their results showed that cuttlefish were able to detect contrast differences of at least 15%, which Mäthger and her colleagues suspect might be a critical factor in uncovering what determines camouflage patterning in cuttlefish.

Despite these results, the vexing question of how cuttlefish master the task of camouflage in low-contrast, color-rich environments such as those found at shallow depths of water, remains to be answered. Mäthger and her colleagues are currently looking at cuttlefish contrast sensitivity in more detail. “Our result that cuttlefish are able to detect contrast differences of at least 15%, is only an upper limit,” says Mäthger. “It’s certainly not the contrast threshold, which we would like to know. It seems that cuttlefish camouflage themselves by matching intensities of objects in the environment and we’re collecting data to test see whether this is really the case.”

In addition to looking at contrast between different objects, Mäthger and her colleagues are testing a variety of other optical clues, in particular, cuttlefish perception of object edges, brightness, and sizes of objects.

Cuttlefish are cephalopods, relatives of octopuses and squid, and are found in all marine habitats worldwide; they are particularly abundant around coral reefs and temperate rock reefs in which the visual habitat is richly varied. Cephalopods can change their appearance with a speed and diversity unparalleled in the animal kingdom. Some squids, octopuses, and cuttlefish can show 30-50 different appearances. Their sophisticated neural control of the skin make cuttlefish an excellent model for studying camouflage.

Gina Hebert | EurekAlert!
Further information:
http://www.mbl.edu

More articles from Life Sciences:

nachricht Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>