#eye

#eye

Yes, Your Eye Color Can ChangeWe are used to kittens having blue eyes when they first open them, which turn to yellow, green, or brown after a couple of months. This happens in human babies, too, more than you'd expect. In one study, a third of newborns eyes had changed color by the time they were two years old. The most common change was baby blue eyes to turn darker, but there were some cases of infant eye color changing to a lighter hue. When eyes turn from blue to brown, hazel, or green, it's because the body is depositing more melanin into the iris. But the change isn't restricted to babies... some people's eye color changes during childhood or even early adulthood. Scientists still don't know why these changes take place after infancy, but suspect it's a combination of genetics and environment. The color of one's eyes can change in adulthood, too, for several reasons. An infection can alter the amount of melanin in the eyes. Actress Mila Kunis suffered an infection that caused her left eye to turn green while her right eye remained brown. One Ebola infection survivor's eyes turned from blue to green because the virus remained in his eyes after it left the rest of his body. Read about the many ways eyes can change color at BBC Future. -via Damn Interesting (Image credit: Natjja4) #eye #eyecolor

390 Million Years Ago, This Trilobite Developed a "Hyper-Eye" with 200 LensesBack in the 1970s, radiologist and amateur paleontologist Wilhelm Stürmer took some x-ray images of trilobites of the suborder Phacopina from the Devonian age. (These were arthropods that became extinct about 251 million years ago.) At the time, Stürmer believed that the filaments under the arthropod's eyes were nerves that served as a light guiding system. Unfortunately, scientists did not believe his theory. Now, decades later, a re-examination of Stürmer's images proved that his conjectures were true after all.The research team today has learned that the trilobite's eye system was unique. Each eye contained about 200 large lenses that spanned six normal compound-eye-facets, which formed a compound eye. Furthermore, scientists have identified a structure thought to directly process visual information from this hyper-eye.It is believed that this hyper-eye was an evolutionary adaptation, as the trilobite lived in low-light environments.Learn more about this trilobite and the study over at the University of Cologne.(Image via University of Cologne)#Evolution #Trilobite #Eye #XrayImageAnalysis #Adaptation

Sea Turtle Has a 'Third Eye' That Senses Change in SeasonsLeatherback sea turtle (Dermochelys coriacea) has a pink spot/white spot on top of its head that act as a "third eye" to help it sense the change in seasons.Every summer, the sea turtle swim thousands of miles from their breeding ground in tropical waters to feed in cooler parts of the ocean - but how does it know how to begin its journey back? Now, a new anatomical study showed that the pink/white spot on top of its head has a markedly thinner layer of bone and cartilage thus allowing the underlying pineal gland of the turtle's brain to sense subtle changes in sunlight that accompanies the changing of the seasons - thus acting as a "skylight" sensor.Image: J. Davenport et al.#turtle #leatherbackseaturtle #thirdeye #eye #pinealgland #anatomy #animalmigration