“Shark Vision”

http://news.bbc.co.uk/earth/hi/earth_news/newsid_9365000/9365750.stm

Researchers in Australia have discovered that sharks are completely colorblind. Except for loan sharks, who only see green.

Of 17 shark species examined, none could see color. Which is why they prefer black-and-white movies.

The researchers had hypothesized that sharks may not see different colors when they noticed that sharks never use crayons.

If sharks really are colorblind, this weakness could be exploited by their enemies, the Jets.