Color vision found in fish that live in near darkness

MAY 9, 2019

by University of Maryland

An international team of researchers discovered a previously unknown visual system that may allow color vision in deep, dark waters where animals were presumed to be colorblind. The research appears on the cover of the May 10, 2019, issue of the journal Science.

Vertebrate eyes use two types of photoreceptor cells to see—rods and cones. Both rods and cones contain light-sensitive pigments called opsins, which absorb specific wavelengths of light and convert them into electrochemical signals that the brain interprets as color. The number and type of opsins expressed in a photoreceptor cell determine the colors an animal perceives.

"This is the first paper that examines a diverse set of fishes and finds how versatile and variable their visual systems can be," said Karen Carleton, a biology professor at the University of Maryland and co-author of the paper. "The genes that determine the spectrum of light our eyes are sensitive to turn out to be a much more variable set of genes, causing greater visual system evolution much more quickly than we anticipated."

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Female lemurs with color vision provide advantages for their group

Date: December 5, 2016

Source: University of Texas at Austin (UT Austin)

Female lemurs with normal color vision, as well as their cohabitating colorblind group members, may have selective advantage over lemur groups whose members are all colorblind, according to anthropologists at The University of Texas at Austin.

Unlike other placental mammals, Old World monkeys, apes and humans are unique in displaying "normal" color vision -- or trichromacy. However, New World monkeys, or primates indigenous to the Western Hemisphere, are primarily red/green colorblind -- or dichromatic -- with trichromatic color vision occurring in some females but no males. Several scientific theories exist on how color vision diversity among these species has maintained over the years, but new research on Verreaux's sifaka, a species of lemur native to Madagascar, challenges existing hypotheses for the evolution of color vision in both Old and New World monkeys.

In the study, appearing in "Scientific Reports," UT Austin anthropologists documented trichromacy in a population of wild lemurs and its effects on fitness, such as reproductive success and feeding behavior. The study was conducted at UT Austin anthropology professor Rebecca Lewis's Ankoatsifaka Research Station at Kirindy Mitea National Park in western Madagascar, where she has accumulated a decade's worth of behavioral, health, demographic and habitat data on the sifaka.

 

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Aggressive Mantis Shrimp Sees Color Like No Other

By Stephanie Pappas, Senior Writer | January 23, 2014 02:00pm ET

The colorful mantis shrimp is known for powerful claws that can stun prey with 200 lbs. (91 kilograms) of force. Now, new research finds that these aggressive crustaceans are weird in another way: They see color like no other animal on the planet.

In fact, the 400-million-year-old visual system of the mantis shrimp works more like a satellite sensor than any other animal eye, said study researcher Justin Marshall, a neurobiologist at theUniversity of Queensland in Australia. Instead of processing ratios of stimulation from just a few color receptors, the mantis shrimp has 12 — and it seems to use them to recognize color with minimal effort.

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Deep-sea crabs have colour vision

Deep-sea crabs have a type of colour vision despite living up to 1000m below the surface, say scientists.

Investigating the "murky depths", US-based researchers recorded the glow of tiny bioluminescent species using a submersible vehicle.

The team also studied how crustaceans react to this light, and found previously unknown sensitivities to blue and ultra violet wavelengths.

They suggest crabs use their colour vision to discern edible food.

The research, conducted in the Bahamas, is published in two papers in the Journal of Experimental Biology and was undertaken with Professor Sonke Johnsen from Duke University in North Carolina, US, Dr Tamara Frank from Nova Southeastern University in Florida, US and colleagues.

Read more:  http://www.bbc.co.uk/nature/19488659