Greenland sharks may live for 400 years without suffering the kind of retinal decline normally associated with aging.

Shark orders include highly specialised species such as sawsharks, angel sharks and bullhead sharks.

Add Yahoo as a preferred source to see more of our stories on Google. Shark activity off the coast of Massachusetts increased over the past week, with a half dozen sightings reported in area waters.

It's Shark Week — and for all their mystery, power and danger, some shark species are also prized as seafood. Shark is eaten in many parts of the world and is especially popular in Brazil, Iceland, ...