under the sea you can find some ever dangerous animals,too.the hammerhead shark has a T-shaped head and can grow to over 4 metres long. it is quite at home in the warm waters around the world and may attack the creatures it comes across, ever humans.the jellyfish has an umbrella-shaped,see-through body with long arms called tentacles,there are about 200 different kinds of jellyfish-varying in shape,size and colour-and 70 of them have sting cells in their tentacles.