Featured Research

from universities, journals, and other organizations

All the better to see you with, my dear! New fish discovered with upward looking eye

Date:
March 19, 2014
Source:
Universitaet Tübingen
Summary:
A fish with a previously unknown type of eye has been discovered by scientists. The aptly-named glasshead barreleye lives at depths of 800 to 1000 meters. It has a cylindrical eye pointing upwards to see prey, predators or potential mates silhouetted against the gloomy light above. But the eye also has a mirror-like second retina which can detect bioluminescent flashes created by deep-sea denizens to the sides and below, report researchers.

The deep-sea glasshead barreleye, rhynchohyalus natalensis.
Credit: D. A. Flynn (CSIRO)

The University of Tübingen's Institute of Anatomy has discovered a fish with a previously unknown type of eye. The aptly-named glasshead barreleye lives at depths of 800 to 1000 meters. It has a cylindrical eye pointing upwards to see prey, predators or potential mates silhouetted against the gloomy light above. But the eye also has a mirror-like second retina which can detect bioluminescent flashes created by deep-sea denizens to the sides and below, reports Professor Hans-Joachim Wagner in the latest Proceedings of the Royal Society.

Related Articles


Professor Wagner examined an 18cm long glasshead barreleye, rhynchohyalus natalensis, caught in the Tasman Sea between Australia and New Zealand, as part of an international research project. The results were unexpected -- reflector eyes are usually only found in invertebrates, such as mollusks and crustaceans, although one other vertebrate, the deep-sea brownsnout spookfish or dolichopteryx longipes, also uses a combination of reflective and refractive lenses in its eyes. The light coming from below is focused onto a second retina by a curved mirror composed of many layers of small reflective plates made of guanine crystals, giving the fish a much bigger field of vision.

The glasshead barreleye is therefore one of only two vertebrates known to have reflector eyes; but significantly, although rhynchohyalus natalensis and dolichopteryx longipes belong to the same family, their reflective lenses have a different structure and appear to have developed from different kinds of tissue. That indicates that two related but different genera took different paths to arrive at a similar solution -- the reflective optics and a second retina to supplement the limited vision of the conventional refractive cylindrical eye.

The prisms in the brownsnout spookfish eye grew out of a layer of pigment on the retina and the angle of the reflective crystals varies depending on their position within the mirror, but in the glasshead barreleye, the crystals are flatter and images are formed depending on the roundness of the reflective surface. "The mirror here is formed from the silvery skin of the eye, and the crystals are arrayed almost parallel to the surface of the mirror," says Wagner. Models of the reflector showed that it is capable of throwing a bright, sharp image onto the retina below. "Obviously, a broad field of vision is an advantage even at great depths if similar structures develop independently to ensure it."


Story Source:

The above story is based on materials provided by Universitaet Tübingen. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. C. Partridge, R. H. Douglas, N. J. Marshall, W.- S. Chung, T. M. Jordan, H.- J. Wagner. Reflecting optics in the diverticular eye of a deep-sea barreleye fish (Rhynchohyalus natalensis). Proceedings of the Royal Society B: Biological Sciences, 2014; 281 (1782): 20133223 DOI: 10.1098/rspb.2013.3223

Cite This Page:

Universitaet Tübingen. "All the better to see you with, my dear! New fish discovered with upward looking eye." ScienceDaily. ScienceDaily, 19 March 2014. <www.sciencedaily.com/releases/2014/03/140319094007.htm>.
Universitaet Tübingen. (2014, March 19). All the better to see you with, my dear! New fish discovered with upward looking eye. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2014/03/140319094007.htm
Universitaet Tübingen. "All the better to see you with, my dear! New fish discovered with upward looking eye." ScienceDaily. www.sciencedaily.com/releases/2014/03/140319094007.htm (accessed October 31, 2014).

Share This



More Plants & Animals News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Watch Baby Goose Survive A 400-Foot Cliff Dive

Watch Baby Goose Survive A 400-Foot Cliff Dive

Buzz60 (Oct. 31, 2014) — For its nature series Life Story, the BBC profiled the barnacle goose, whose chicks must make a daredevil 400-foot cliff dive from their nests to find food. Jen Markham has the astonishing video. Video provided by Buzz60
Powered by NewsLook.com
World's Salamanders At Risk From Flesh-Eating Fungus

World's Salamanders At Risk From Flesh-Eating Fungus

Newsy (Oct. 31, 2014) — The import of salamanders around the globe is thought to be contributing to the spread of a deadly fungus. Video provided by Newsy
Powered by NewsLook.com
Alcoholic Drinks In The E.U. Could Get Calorie Labels

Alcoholic Drinks In The E.U. Could Get Calorie Labels

Newsy (Oct. 31, 2014) — A health group in the United Kingdom has called for mandatory calorie labels on alcoholic beverages in the European Union. Video provided by Newsy
Powered by NewsLook.com
Malaria Threat in Liberia as Fight Against Ebola Rages

Malaria Threat in Liberia as Fight Against Ebola Rages

AFP (Oct. 31, 2014) — Focus on treating the Ebola epidemic in Liberia means that treatment for malaria, itself a killer, is hard to come by. MSF are now undertaking the mass distribution of antimalarials in Monrovia. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins