Eventually, the light-sensitive spot evolved into a retina, the layer of cells and pigment at the back of the human eye. Over time a lens formed at the front of the eye. It could have arisen as a ...

So, at the outset, nocturnal eyes gather more light than human eyes ... It's made up of at least 10 distinguishable layers, and is packed with more sensory nerve cells than anywhere else in ...

On the left: diagram of the eye. On the right: layers within the retina and the adjacent choroid. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to ...

The mucus comes from the conjunctiva which is the transparent tissue covering the whites of the eye and internal surface of ...

Do you find yourself frequently reaching for over-the-counter eye drops to help relieve your gritty, scratchy and irritated ...

A new therapy repairs corneal damage to a patient's eye using stem cells from their other, healthy eye. A new stem cell ...

Photopsia is the medical name for these flashes, and this phenomenon usually occurs when there are changes inside the eye. The retina is a thin layer of tissue that receives light at the back of ...

Pinhole camera eyes, lacking a lens and cornea, are found in the nautilus today. The final big change is to evolve a lens. This probably started out as a protective layer of skin that grew over ...