Ed

In a word, many sharks are able to see in color. It was once believed that sharks weren't able to perceive color. This all-encompassing conclusion was in part based on the lack of body colors and visual displays interms of mating, and that the sharks predated the amphibians. This was found to be false by the work of Sam Gruber who showed that predatory sharks had indeed good to excellent color vision. Later studies found that the sharks had more then excellent color vision, the pinnacle being in the makos, of which the white shark evolved from (the megatooth was an endpoint in evoluion and died out by the Miocene). Recent evidence has demonstrated that whites are able to perceive color and a high level of visual accuity in exceptionally low light levels.At what point rods take over from cones is still open to further research.
The shark sensory suite is actually a wonder: vision, smell, hearing, pressure, electrical signals and taste, all so wonderfully wired together into series of smart nerves that preprocesses signals before leading to a portion of the brain that is as equally and wonderfully developed, in a sense, beyond primates in certain aspects-if evolutionary sucesses are to be considered a race. Neither system is the strongest, but each senses and provide data that is integrated to create a composite whole picture.
A theory has been postulated that sensory system overlap can provide a virtual sense that biologically doesn't exist yet provides a hunch or perception of something that each sense alone isn't capable of sensing. In other words, sight, sound, smell, taste and the rest have minimal sensory thresholds yet the sum of them all provide a rich sensory picture as if each individual system had indeed did sense. As an analogy to this virtual sense, the "sixth-sense" in humans, many have reported feeling someone hidden or hiding, usually in "hunting" situations (as in a war time setting). An unease, a perception of something when there is no senosry evidence to support the feeling. The author of this theory called it a "second level" sense when he forwarded it in 1980 at the Naval Aircraft Test Center Patuxent River.
I attached a link to a good discussion of shark eyesight. Hope this helps.

: Do sharks see in color? Do their retinas have rods and cones?
: I have seen studies showing sharks' sensitivity to vibration and body fluids
: in the water but haven't heard about the color thing or even if their eyes
: are an important sense for them.
: My job is to teach 6th graders about this type of thing so I'd be interested
: to hear more about your work...

: Ed