Evolution of Sight in the Animal Kingdom

This amazing video produced by the History Channel, Vision and Evolution of the Eye is well worth 40 minutes of your time.  The evolution of visual systems is something that we here at Webvision are very interested in.  Also note that we have an excellent chapter on the Evolution of Phototransduction, Vertebrate Photoreceptors and Retina by Trevor Lamb here on Webvision.

 

This accompanying text below on this post was sent to us by friend of Webvision, Dr. Dominic Man-Kit Lam.  Dr. Lam was born in Swatow, and grew up in Hong Kong. He studied under two Nobel Laureates at Harvard Medical School before joining the Harvard Faculty and subsequently became Professor of Ophthalmology and Chairman of Center for Biotechnology at Baylor College of Medicine in Houston. He is the president of the World Eye Organisation, A charitable organization dedicated to the prevention and treatment of eye disorders for the poor.  Continue reading “Evolution of Sight in the Animal Kingdom”

Blind Kenyan Runner Has Far-Reaching Vision

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NPR has a wonderful story of childhood friends, Henry Wanyoike and Joseph Kibunja who started running together as children 30 years ago and are still running in competition today.  That is a remarkable story enough, but even more compelling is that Wanyoike is blind from a stroke that cost him his sight and Kibunja is his running guide.

It is a wonderful story and well worth the read.  While there, also be sure to stop by the Henry Wanyoike Foundation website, designed to help bring young people together through sport.

 

 

 

Color Blindness: What Does It Look Like?

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One of the common questions people have is what it means to be colorblind since that is one of the common visual deficit manifestations that they can relate to.  Color blindness (pretty good article on Wikipedia there) is very common and just about everyone knows someone who does not see the world quite like they do because of a form of color blindness.

I have a post over on Jonesblog that renders some natural scenes as protanopes, deuteranopes and tritanopes would see them and talks about how to simulate your own images for various forms of color blindness.

Describing Colors To Blind People

Tommy Edison, The Blind Film Critic has been blind since birth.  In this sort video from his Youtube Film Channel, he discusses the concept of color to a person who has never before seen.  Tommy also has lots of additional videos that give some insight into how the blind navigate through life.  For those of us who study vision or are interested in vision, Tommy’s channel is well worth dropping by.

Hat Tip to Laughing Squid.

Was Van Gogh Colorblind?

A friend of mine (and amazing landscape/nature photographer) Jim Goldstein sent me a Tweet and pointed out simmering new conjecture in the art community that Vincent Van Gogh might have been color blind, specifically a protanope.  I seem to remember some discussion of this years ago, particularly given that one can rather nicely simulate both protanopia and deuteranopia in Adobe Photoshop with built in filters (View>Proof Setup>Protanopia/Deuteranopia).  However, the current speculation comes about from Kazunori Asada who wrote up a Tumbler blog entry here describing how he came about his idea and a subsequent app he wrote to simulate color vision and color blindness.  The image above shows Kazunori Asada’s approximation of Van Gogh’s Starry Night and Flowering Garden with Path with the original on the left and the Asada transform approximation on the right.

Continue reading “Was Van Gogh Colorblind?”

Your Central Visual Field by XKCD

This little bit of visual comic brilliance comes to you by way of XKCD. Click here for the full size image from the XKCD website.  XKCD is one of my all time favorite websites with a new comic posted fairly routinely.  I’ve been following the author of XKCD, Randall Munroe since his very first postings on XKCD.  He is a kind of genius, there is no doubt and I always love to see his perspective on “life, the universe and everything” to quote another favorite author.

Age-Related Changes In The Daily Rhythm of Photoreceptor Functioning And Circuitry In A Melatonin-Proficient Mouse Strain

This is an interesting study in PLoS One examining the involvement of melatonin in the retina, particularly in the survival of retinal neurons through aging studies in CH3-f+/+ mice, a melatonin proficient mouse strain.  As expected, certain physiological measures (a and b waves) are lost during aging, and in particular, the daily circadian rhythms of those measures.  However, the authors, Kenkichi Baba, Francesca Mazzoni, Sharon Owino, Susana Contreras-Alcantara, Enrica Strettoi and Gianluca Tosini did something really interesting and added exogenous melatonin to their assay and concluded that responsiveness of exogenous melatonin is also reduced during aging.

Lobster Eye Design Informs NASA X-Ray Detector

In a classic case of biology informing other areas of science, we have NASA scientists at Goddard Space Flight Center, Scott Barthelmy, Gerry Skinner and Jordan Camp who have built a new X-Ray astronomy instrument inspired by the design of a lobster eye with long, compound ommatidium or eye-elements that capture light from a wide number of angles. Continue reading “Lobster Eye Design Informs NASA X-Ray Detector”

Giant Squid Eyes

A recent paper by Dan-Eric Nilsson, Eric J. Warrant, Sönke Johnsen, Roger Hanlon and Nadav Shashar reports on the eyes of some of the most mysterious of creatures, Architeuthis and Mesonychoteuthis, the giant and colossal deep sea squid respectively. We here at Webvision love all things retina and would deeply love to get our hands on the retinas of these creatures to perform CMP and explore them through connectomics, to understand how the retinas are constructed, how they evolved and how different/similar they are to other organisms. For now, we have to satisfy ourselves with interesting papers from colleagues on descriptions of eyes from squid the authors have examined as well as their theories for how the squid use their eyes to track prey and predators by seeing the bioluminescence that follows objects as they transit benthic waters.

Continue reading “Giant Squid Eyes”