So serpents don't need spectacles

Snakes. Why did it have to be snakes?

Think of it as rolling snake eyes, but in a good way.

A new study from the University of Waterloo shows that snakes can optimize their vision by controlling the blood flow in their eyes when they perceive a threat.

Kevin van Doorn, PhD, and Professor Jacob Sivak, both from the Faculty of Science, discovered that the coachwhip snake’s visual blood flow patterns change depending on what’s in its environment. The findings appear in the most recent issue of the Journal of Experimental Biology.

“Each species' perception of the world is unique due to differences in sensory systems,” said van Doorn, a teaching assistant at the School of Optometry & Vision Science.

Instead of eyelids, snakes have a clear scale called a spectacle. It works like a window, covering and protecting their eyes. Spectacles are the result of eyelids that fuse together and become transparent during embryonic development.

When van Doorn was examining a different part of the eye, the illumination from his instrument detected something unusual.

Surprisingly, these spectacles contained a network of blood vessels, much like a blind on a window. To see if this feature obscured the snake’s vision, van Doorn examined if the pattern of blood flow changed under different conditions.

When the snake was resting, the blood vessels in the spectacle constricted and dilated in a regular cycle. This rhythmic pattern repeated several times over the span of several minutes.

But when researchers presented the snake with stimuli it perceived as threatening, the fight-or-flight response changed the spectacle’s blood flow pattern. The blood vessel constricted, reducing blood flow for longer periods than at rest, up to several minutes. The absence of blood cells within the vasculature guarantees the best possible visual capacity in times of greatest need.

“This work shows that the blood flow pattern in the snake spectacle is not static but rather dynamic,” said van Doorn.

Next, the research team examined the blood flow pattern of the snake spectacle when the snake shed its skin. They found a third pattern. During this time, the vessels remained dilated and the blood flow stayed strong and continuous, unlike the cyclical pattern seen during resting.

Together, these experiments show the relationship between environmental stimuli and vision, as well as highlight the interesting and complex effect blood flow patterns have on visual clarity. Future research will investigate the mechanism underlying this relationship.

“This research is the perfect example of how a fortuitous discovery can redefine our understanding of the world around us,” said van Doorn.

The Natural Sciences and Engineering Research Council of Canada supported this project.

 

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Don't panic: it's Hadfield's guide to the galaxy

Retired Canadian Astronaut Col. Chris Hadfield's new book contains survival tips for those of us on Spaceship Earth.

An Astronaut's Guide to Life on Earth is now available at the Bookstore in South Campus Hall. In the book, Hadfield takes readers deep into his years of training and space exploration to show how to make the impossible possible.

Through eye-opening, entertaining stories filled with the adrenaline of launch, the mesmerizing wonder of spacewalks, and the measured, calm responses mandated by crises, he explains how conventional wisdom can get in the way of achievement—and happiness. His own extraordinary education in space has taught him some counterintuitive lessons: don't visualize success, do care what others think, and always sweat the small stuff.

Faculty, staff, students and alumni can receive a 25% off the list price by showing their WatCard.

 

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Waterloo Unlimited grade 11 program open

Waterloo Unlimited's Grade 11 "Design" program is now accepting applications.

From engineering and the environment to science fiction and virtual reality, high school students will spend a week exploring the theme of design with a community of like-minded peers.

The five-day program will run from Monday, March 10 to Friday, March 15, 2014. Lectures, small group sessions, seminars and other activities are planned.

The application deadline is Thursday, December 19.

Waterloo Unlimited is the University of Waterloo's on-campus enrichment opportunity for high school students in grades 10, 11, and 12. Offered during the school year, Unlimited brings together curious, motivated, well-rounded teens from across the country.

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Feds Used Books launches mobile app

by Jacqueline Martinz.

Feds Used Books, which is owned and operated by the Federation of Students, has launched a mobile app that allows users to learn how much money they’d make by selling a textbook. Users can download the app by visiting iTunes or Google Play app stores on their smartphone or the Feds Used Books website, and then use their phone to scan the barcode numbers found on textbooks.

“If the book is no longer in use at the University of Waterloo, the app will show if it’s possible to export it and display a price,” said John Jongerius, the manager of Feds Used Books. “The export price is what the store will pay a customer if we’re able to sell their book to a company in the United States. Feds Used Books works with companies in the US that supply textbooks to colleges and universities.”

The export option is also beneficial because all payments from the store will be made in cash up-front. If no price is displayed when students use the app to scan their textbook, there are other ways for them to sell it. Feds Used Books offers consignment for books still needed at the University of Waterloo. More information about consignment and Feds Used Books is available online.

 

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Employees to celebrate milestones this week

The annual recognition reception for staff members who have been with the university for 5, 10, 15, 20, 25, 30, 35, 40 and 45(!) years will be taking place this Thursday, November 21 from 4:00 p.m. to 6:00 p.m. in the Centre for Environmental Information Technology's Earth Sciences Museum.

According to Human Resources, this year a total of 275 employees are reaching a "year of recognition." 116 employees have hit the 5-year mark, 79 employees have been here 10 years, 54 have been employed for 15 years, 10 employees are celebrating 20 years, 11 are at the 30-year mark, 4 have hit the big 4-0, and one stalwart staffer is being recognized for a whopping 45 years of service.

Congratulations all!

 

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