As any scuba diver or snorkeler will surely tell you, underwater vision can be a fascinating and rewarding experience. The reason why your unaided vision goes blurry underwater requires a basic discussion of the behaviour of light rays and the human eye.

Sunglasses aren’t just ideal tools for completing outfits. Apart from being great fashion accessories, the right pair of shades also provides excellent protection against glare, ultraviolet (UV) rays, and everyday physical hazards. One thing to keep in mind, however, is that not all kinds are created equal. Knowing what type of sunglasses to look for—and what defence they offer—is critical to making your next purchase.

Though I knew that the recovery from LASIK is usually quick and virtually painless, I was still nervous when I went in for my procedure.

According to a long-term research study from the University of Copenhagen, it’s likely that anyone with blue eyes shares a common ancestor. While variation in human eye colour is caused by at least 15 separate genes, mutation in a single gene produces blue, and can be traced to a specific DNA location.

Contact sports are risky, and not being able to see clearly makes them even riskier.