Their sharp triangular teeth are heavily serrated and have an elongated dorsal fin that is easy to identify. Great Hammerhead ...

That is why shark teeth are the most abundant vertebrate fossil material on the Earth and in the sea. Scalloped hammerhead on the reef. NOVA: Do sharks have to keep swimming to breathe?

Hammerhead sharks don’t lay eggs ... and these babies are self-sufficient with teeth and jaws, ready to survive on their own. Access to a hammerhead embryo is very rare, which is what makes ...

Dr. Peter Klimley is a man who has held his breath and dived down 100 feet to hand-tag hammerhead sharks with a dart gun. He has even dressed up as a killer whale, complete with towering black ...