Simple Eyes of Only Two Cells Guide Marine Zooplankton to the Light

piggy submitted, created time 1 week 1 day (www.sciencedaily.com)

Researchers unravel how the very first eyes in evolution might have worked and how they guide the swimming of marine plankton towards light.

Larvae of marine invertebrates – worms, sponges, jellyfish - have the simplest eyes that exist. They consist of no more than two cells: a photoreceptor cell and a pigment cell. These minimal eyes, called eyespots, resemble the "proto-eyes" suggested by Charles Darwin as the first eyes to appear in animal evolution. They cannot form images but allow the animal to sense the direction of light

3 comments | Blog It | Email It | Keywords: phototaxis light plankton vision evolutionary biology eyespots eye evolution eyes

Eyes: A New Window on Mental Disorders

jerry submitted, created time 2 months 2 weeks (www.sciam.com)

Clues about autism, Williams syndrome and the social brain come from tracking eye movements. This method may be useful, researchers say, because it is not necessary for the participant to understand or even know what the researcher is doing.

Submit comment | Blog It | Email It | Keywords: methodology eyes Williams syndrome autism Mental Disorders

Retinal transplants bear threefold fruit

Darkfrog submitted, created time 2 months 3 weeks (www.nature.com)

A formerly clinically blind woman's vision improved from 20/800 to 20/160--from one-fortieth of ordinary vision to one-eighth--after receiving donated retina. Six months after the operation, the started noticing the pendulum in her grandfather clock. For years, she found that she could read large-print books and emails and returned to her hobbies, knitting and sewing. Now, six years after her operation, her vision is fading, but it is still better than it was before the operation

Submit comment | Blog It | Email It | Keywords: age-related macular degeneration opthalmology macular degeneration blindness stem cell research politics bioethics retinitis pigmentosa retina eyes sight vision transplants Vision Problems repair vision

Study says eyes evolved for X-Ray vision

sea-maid submitted, created time 3 months 14 hours (esciencenews.com)

The advantage of using two eyes to see the world around us has long been associated solely with our capacity to see in 3-D. Now, a new study from a scientist at Rensselaer Polytechnic Institute has uncovered a truly eye-opening advantage to binocular vision: our ability to see through things. Most animals — fish, insects, reptiles, birds, rabbits, and horses, for example — exist in non-cluttered environments like fields or plains, and they have eyes located on either side of their head

Submit comment | Blog It | Email It | Keywords: panoramic vision vision sight evolution eyes x-rays X-Ray vision

Slip-eyed flatfish found!

Darkfrog submitted, created time 4 months 3 weeks (www.nature.com)

Although young flatfish have one eye on each side of their heads, the adult flatfish sports both on one side. This allows the fish to lie on the sea floor looking up and still retain its depth perception. This ocular migration has puzzled gradual evolutionists. If the trait evolved gradually over many generations, then why aren't there fossils showing fish with partially migrated eyes?

Well today's Nature posts the discovery of two such fish fossils, blowing a giant raspberry at both creationists and sudden-jump evolutionists alike.

Submit comment | Blog It | Email It | Keywords: fish marine biology flatfish evolution eyes eye punctuated equilibrium creationism creation science Darwin evolutionary biology

Eyeless Worm Senses Light

sea-maid submitted, created time 4 months 3 weeks (sciencenow.sciencemag.org)

Discovery of light-responsive neurons in a nematode may hold clues about eye evolution.

2 comments | Blog It | Email It | Keywords: evolutionary biology eyes light worms

General Model of Vision, Au Naturel

jerry submitted, created time 5 months 3 weeks (www.sciencedirect.com)

Visual stimuli in the laboratory are artificial. How does the visual system process more complex, naturalistic stimuli? In this study, researchers bridge the chasm between artificial and natural stimuli by developing a general model for responses in the lateral geniculate nucleus, the main input to visual cortex.

1 comment | Blog It | Email It | Keywords: visual cortex eyes eye vision visual stimuli

Color is in the eye of the beholder

bianjie submitted, created time 1 year 4 months (www.springer-sbm.com)

The unique makeup of the cells in our retina, as well as the specific physical properties of substances themselves, explain why we occasionally see things change color before our very eyes! Samo and Marko Kreft from the University of Ljubljana in Slovenia investigated this phenomenon using pumpkin seed oil as an example. They have just published their research online in Springer's journal Naturwissenschaften.

Submit comment | Blog It | Email It | Keywords: retina color cells eyes