HOME >> BIOLOGY >> NEWS
In a world of distortion, archer fish learn to judge absolute size of aerial prey

Anyone who has looked at the aerial world during an underwater dive will have marvelled at the distortions in apparent size, shape, and position of aerial objects. In a new study, researchers have shown that archer fish can learn to cope with these strongly viewpoint-dependent distortions, and this ability enables the fish to precisely judge from any underwater viewpoint the absolute size of their aerial prey. The work is reported by Stefan Schuster, now at the University of Erlangen-Nuremburg, and colleagues at the University of Freiburg.

Many animals are able to judge the absolute size of visual objects, a skill that becomes especially useful for tasks such as selecting prey. The ability to judge absolute size, however, requires that the visual system be able to perform a critical correction to account for distance between the eye and the viewed object: dramatic differences in the size of the actual retinal image occur as the distance between viewer and object changes. A situation in which this corrective requirement is especially challenging arises for animals that need to judge the size of aerial prey from an underwater vantage point. Here, as the study of Schuster and colleagues shows, the complex optical situation arising from distance and refraction requires precise understanding of the relationship between an object's apparent size and the fish's relative position to the object.

In the experiments reported by the researchers, archer fish viewed a set of eight disks at various heights above the water surface from various horizontal distances and selected one of the disks as a shooting target based only on its absolute size. Although nave fish often selected disks that would be too large to be swallowed, all could eventually learn to judge absolute size with great precision; in doing so, they perfectly accounted for the complex optical situation posed by their underwater viewpoint. In a series of experiments, the researchers showed that the f
'"/>

Contact: Heidi Hardman
hhardman@cell.com
617-397-2879
Cell Press
6-Sep-2004


Page: 1 2

Related biology news :

1. DuPont scientist named one of the worlds top young innovators by MITs Technology Review Magazine
2. Health of worlds sea lions the focus of Wakefield Symposium
3. Laboratory grows world record length carbon nanotube
4. Improved nutrition could reduce malaria burden worldwide
5. Study shows how consensus is attained in a noisy world
6. MSU group reviews Berkeley venture into brave new science funding world
7. From science fiction to reality: Nanomedicine brings fresh hope to the medical world
8. New world record magnet for chemical and biomedical research
9. Growing new breed of vaccine-producing plants to fight human diseases worldwide
10. Scientists describe the worlds smallest, lightest fish
11. Songbirds escaped from Australasia, conquered rest of world

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/28/2016)... India , April 28, 2016 ... Infosys (NYSE: INFY ), and Samsung SDS, a ... that will provide end customers with a more secure, ... services.      (Logo: http://photos.prnewswire.com/prnh/20130122/589162 ) , ... services, but it also plays a fundamental part in enabling ...
(Date:4/19/2016)... The new GEZE SecuLogic access ... "all-in-one" system solution for all door components. It can ... door interface with integration authorization management system, and thus ... minimal dimensions of the access control and the optimum ... offer considerable freedom of design with regard to the ...
(Date:4/13/2016)... physicians supporting Medicaid patients in Central Florida ... telehealth thanks to a new partnership with higi.   ... can routinely track key health measurements, such as blood ... they opt in, share them with IMPOWER clinicians through ... location at no cost. By leveraging this data, IMPOWER ...
Breaking Biology News(10 mins):
(Date:5/20/2016)... ... May 20, 2016 , ... The leading Regenerative Veterinary Medicine ... experienced veterinary clients have treated over 100 of their own patients with the VetStem ... the highest level of care for their patients. , The veterinarians are Dr ...
(Date:5/20/2016)... (PRWEB) , ... May 20, 2016 , ... Korean researchers ... that it may offer a new way to treat the disease. Surviving Mesothelioma has ... now. , Scientists from several Korean institutions based their mesothelioma study on the ...
(Date:5/19/2016)... ... May 19, 2016 , ... Anton Paar USA, located in Ashland, Virginia ... is complete. The new structure adds a third office building to the current facilities. ... purchased 2.4 acres of land, along with office space adjacent to the previous main ...
(Date:5/19/2016)... There is no saying when ... relentless pressures in pricing and lack in consumer confidence. ... though - numerous opportunities are up for grabs but ... presents four names in this sector: Portola Pharmaceuticals Inc. ... VTAE ), Anthera Pharmaceuticals Inc. (NASDAQ: ...
Breaking Biology Technology:
Cached News: