Artist with 4th Cone Perceives Color in the UV Range

“The human eye is packed with millions of cone-shaped cells that allow for color to be perceived. For those with normal vision, the three types of cones allow vision of about one million distinctive colors,” notes IFL Science. “Some animal species including certain birds, insects, fish, and reptiles, have a fourth type of cone cell that extends color perception into the UV range. Though evolution has mostly scrubbed that fourth cone from the mammalian lineage, there is evidence that a small group of humans may have a genetic variant that allows for tetrachromacy. Concetta Antico, an Australian artist [one of her landscapes to the right] , was confirmed to be a tetrachromat in 2012.” Read more.

Dead Cone Cells Kill Rod Cells

“There are two major light receptor cells in the mammalian eye: rods and cones. New research by scientists from Duke University have shown that dying cone cells can trigger the demise of healthy rod cells, leading to the loss of vision,” according to Medical News Today. “The study by Kyoung-in Cho and colleagues, published in the journal PLOS Genetics, showed that when a multifunctional protein known as 'Ran-binding protein 2' (RanBP2) is removed from cone cells it causes not only those cells to die but also results in the demise of the healthy rod cells in the eye. The authors also show that the rod and cone cells undergo a cascade of distinct and unusual events as they are dying. The demise of these cells can play a part in diseases such as retinitis pigmentosa and age-related macular degeneration (AMD).” Read more.