Corals 4/22/2008

Coral are found in the sea. They are marine organisms.

They first appeared 542 million years ago.

Some forms of coral become hard as they ooze out calcium carbonate.

The hard rocks that we find in the ocean are fossils of such marine organisms.

Such hard rocks together can form an island on its own. Corals can alter their skeletons to match the chemistry of the seawater – the only known animal to do this. A natural bridge we saw in Aruba was made out of coral. Coral reefs are important breeding and feeding grounds for many ocean species. They also protect the shore. We use coral to make natural tiles for homes.