A 5 foot long frill shark swims in a tank after being found by a fisherman in 2007 in Numazu, Japan. The frill shark, also known as a frilled shark, usually lives at a depth of about 2,000 feet, making it very rare for this shark to be found alive at sea level. Its body shape and the number of gills are similar to fossils of sharks which lived 350,000,000 years ago.
A wider view of the frilled shark swimming in a tank after being found by a fisherman at a bay in Numazu, Japan.
An extremely rare fluorescent yellow Port Jackson shark is shown to the public at the Sydney Aquarium in 2004. The shark derives its unusual bright yellow coloring from a rare form of albinism, a problem for the sharks as they normally lie on the seabed trying to camouflage themselves from predators.
An Atlantic basking shark off the coast of Massachusetts. Researchers using high-tech satellite tags to track the winter movements of the Atlantic basking shark found out that the world's second-largest fish winters in the tropical Caribbean, far from the cold waters off Cape Cod and Canada where it was formerly thought to linger year-round.
A saw shark swims at the Epson Aqua Stadium in Tokyo, Japan.
A snorkeler swims next to a whale shark as it is fed from a feeder boat off the beach of Tan-awan, Oslob, in the southern Philippines island of Cebu. Whale sharks are lured to the Tan-awan coastline of the Oslob district by fishermen who hand feed them small shrimp, drawing divers and snorkelers to see the highly sought-after animals, known as gentle giants of the sea. But the practice has sparked fierce debate on the internet and among biologists, who decry it as unnatural.
A man holds a Wobbegong shark in Sydney before releasing it into the Pacific Ocean. Seven captive-bred Wobbegong sharks were released as part of a research project being undertaken by the Sydney Institute of Marine Science to find out more about the secret life of Sydney's Wobbegong sharks.
A Big Eye Thresher Shark swims in the Gulf Stream off Fort Lauderdale, Fla.
A rare goblin shark catch from a fisherman in Key West, Fla.
Enya Kim of the natural history department at auctioneers Bonhams & Butterfields stands inside one of the world's largest set of shark jaws, comprised of about 180 fossil teeth from the prehistoric species Carcharocles megalodon, which grew to the size of a school bus.