Related topics: brain · nerve cells · current biology · retina

Chemists discover how blue light speeds blindness

Blue light from digital devices and the sun transforms vital molecules in the eye's retina into cell killers, according to optical chemistry research at The University of Toledo.

DNA shows first modern Briton had dark skin, blue eyes

The first modern Briton had dark skin and blue eyes, London scientists said on Wednesday, following groundbreaking DNA analysis of the remains of a man who lived 10,000 years ago.

The space rock that hit the moon at 61,000 kilometers an hour

Observers watching January's total eclipse of the Moon saw a rare event, a short-lived flash as a meteorite hit the lunar surface. Spanish astronomers now think the space rock collided with the Moon at 61,000 kilometres an ...

Laser pioneers win Nobel Physics Prize

Three scientists on Tuesday won the Nobel Physics Prize, including the first woman to receive the prestigious award in 55 years, for inventing optical lasers that have paved the way for advanced precision instruments used ...

SpaceX satellites pose new headache for astronomers

It looked like a scene from a sci-fi blockbuster: an astronomer in the Netherlands captured footage of a train of brightly-lit SpaceX satellites ascending through the night sky this weekend, stunning space enthusiasts across ...

Extinct monitor lizard had four eyes, fossil evidence shows

Researchers reporting in Current Biology on April 2 have evidence that an extinct species of monitor lizard had four eyes, a first among known jawed vertebrates. Today, only the jawless lampreys have four eyes.

Do we read differently on paper than on a screen?

On a global scale, we are reading like never before and are spending more and more time glued to a screen. In fact, we read digital media every single day, whether it is on Facebook or in discussion forums. In total, there ...

Why huskies have blue eyes

DNA testing of more than 6,000 dogs has revealed that a duplication on canine chromosome 18 is strongly associated with blue eyes in Siberian Huskies, according to a study published October 4, 2018, in the open-access journal ...

Vision, not limbs, led fish onto land 385 million years ago

A provocative new Northwestern University and Claremont McKenna, Scripps and Pitzer colleges study suggests it was the power of the eyes and not the limbs that first led our ancient aquatic ancestors to make the momentous ...

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Eye

Eyes are organs that detect light, and send signals along the optic nerve to the visual and other areas of the brain[citation needed]. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in cnidaria, molluscs, chordates, annelids and arthropods.

The simplest "eyes", such as those in unicellular organisms, do nothing but detect whether the surroundings are light or dark, which is sufficient for the entrainment of circadian rhythms. From more complex eyes, retinal photosensitive ganglion cells send signals along the retinohypothalamic tract to the suprachiasmatic nuclei to effect circadian adjustment.

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