Evolutionary replacement of UV vision by violet vision in fish

Paleomolecular biology unravels the evolutionary mystery of vertebrate UV vision.

F rom the detection of a changing traffic light to the relaxing sight of Vincent van Gogh’s ‘‘Sunflower,’’ color vision plays an important role in our lives. But, to the eyes of a hummingbird or goldfish, we humans are partially color-blind, as they can see what is known as UV, to which we are simply blind. How did we lose this sensitivity, or, alternatively, how did they acquire it? In this is...

Vision in Hyphema

In-vivo fish sorting by computer vision

An image-processing algorithm, applied to images of common carp (Cyprinus carpio), St. Peter’s fish (Oreochromis sp.) and grey mullet (Mugil cephalus), successfully discriminated among the species. Fish images were acquired while they were swimming in an aquarium with their side to the camera. The algorithm was based on the method of moment-invariants (MI) coupled with geometrical consideration...

The Colour Vision of Fish

At one time during the past few months the writer's attention was called to the following statement made in January I926 by an eminent surgeon: "In fishes a falci-ft \form ligament is attached to the back of the lens and to the back of the eye for N /fX,E1 focusing. They have no color vision. This fact will be disputed by those who sell q .; ~~~artificial flies at high prices.""5 A subse-"~ Xe\...

Effect of Sports Vision on Vision Perception and Decision Making in Handball Referees

The purpose of the current study was to determine the effect of sport vision training on vision perception and decision making of handball referees. In this semi-experimental study, 30 handball referees were Participated among all the referees working in the Iranian Handball Premier League, then the selected referees divided into 2 sport vision training and control groups, randomly. The study i...