Subscribe free to our newsletters via your
. 24/7 Space News .




WATER WORLD
Twilight zone sharks have special eyes to see in the dark
by Brooks Hays
Washington (UPI) Aug 7, 2014


disclaimer: image is for illustration purposes only

Deep in the sea, where the light from above begins to fade out -- a vast expanse known as the twilight zone -- there are strange glow-in-the-dark sharks. New research shows these sharks possess highly evolved eyes, enabling them to see in the dark and pick up light signals from their bioluminescent friends and enemies.

"There are about 50 different shark species that are able to produce light -- about 10 percent of all currently known sharks," Dr. Julien Claes, a marine biologist at the at The Catholic University of Louvain in Belgium, recently told Live Science.

Claes and a team of researchers discovered these bioluminescent sharks have a higher density of light-sensitive cells in their retinas, allowing them to pick out light and shadow when the differences between the two are minute.

In addition to looking at their eyes, researchers studied the ways these twilight zone sharks give off their own light -- an attempt to camouflage their bodies in the dim, but not pitch black, surroundings. Scientists also found many of these sharks have a transparent gap atop their eyelids, suggesting they interpret the levels of sunlight filtering down from above and then adjust their bioluminescence to blend in.

"That's always intriguing [to me] how an animal monitors both the down-welling light and its own bioluminescence to match the two," Julian Partridge, researcher at the University of Western Australia, told Australia's ABC.

Partridge is co-author of a new paper on the ways these sharks see and emit light in these lonely depths. The study was recently published in PLOS ONE.

Because these sharks use their light giving properties to communicate and locate prey, their eyes must constantly adjust depending on what the shark is looking for. Researchers suggest that this complexity is evidence that their eyes and bioluminescence evolved in conjunction -- a tandem system.

"This teaches us new things about the deep sea which is the biggest living space on the planet, and yet it's also the environment we know least about," Partridge added.

.


Related Links
Water News - Science, Technology and Politics






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








WATER WORLD
Bigeye Tuna Study in Northwest Atlantic Uses New Tracking Methods
Amherst MA (SPX) Aug 05, 2014
A first-of-its-kind study of bigeye tuna movements in the northwestern Atlantic Ocean led by Molly Lutcavage, director of the Large Pelagics Research Center at the University of Massachusetts Amherst, found among other things that these fish cover a wide geographical range with pronounced north-south movements from Georges Bank to the Brazilian shelf, and they favor a high-use area off Cape Hatt ... read more


WATER WORLD
China to send orbiter to moon and back

August supermoon will be brightest this year

Manned Moon Mission to Cost Russia $2.8 Bln

Tidal forces gave moon its shape

WATER WORLD
Opportunity Heads to 'Marathon Valley'

NASA Mars Curiosity Rover: Two Years and Counting on Red Planet

Robotic Rock Climbers Could Uncover Clues to Mars' Past

Russia To Construct Landing Pad For ExoMars Mission

WATER WORLD
NASA Selects Proposals for Advanced Energy Storage Systems

NEEMO 18 Aquanauts Complete Underwater Mission

NASA Selects Innovative Advanced Concepts For More Study

NASA's Space Launch System Boosters Office Completes Critical Design Review

WATER WORLD
More Tasks for China's Moon Mission

China's Circumlunar Spacecraft Unmasked

China to launch HD observation satellite this year

Lunar rock collisions behind Yutu damage

WATER WORLD
Robonaut Upgrades, Spacewalk Preps and Cargo Ops for ISS Crew

US EVAa Delayed; Crew Preps For Russian EVA, Robonaut Upgrades

Europe's Fifth and Final Resupply Ship Launches to Station

Science and Spacesuit Work While ATV-5 Preps for Launch

WATER WORLD
Russia to Decide on Future of Sea Launch Project by End of 2014

SpaceX launches AsiaSat8 into orbit via Falcon 9 rocket

United Launch Alliance Launches Two Rockets in Just Four Days

AsiaSat 8 Successfully Lifts Off

WATER WORLD
Rotation of Planets Influences Habitability

Planet-like object may have spent its youth as hot as a star

Young binary star system may form planets with weird and wild orbits

Hubble Finds Three Surprisingly Dry Exoplanets

WATER WORLD
USN Moderates CubeSat RF Communications Standards Meeting

IT outsourcing boom boosts struggling Bulgaria

NASA Engineer Set to Complete First 3-D Printed Space Cameras

Disney develops tool to design inflatable characters and structures




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.