Coral Reef Spawning
Coral reefs regenerate themselves. Some corals are hermaphroditic, releasing packages of eggs and sperm. Somehow, it works out that dozens of different species release eggs and sperm at the same time. They float together and begin fertilization, creating larvae. The larvae then settles, and morphs into a polyp. The polyps secrete a hard skeleton of limestone. Slowly and gradually, a huge coral reef is formed. They are the largest structures built by living creatures in the world, and take millions of years to build. But it only takes a little time for careless divers, boaters, and global warming to destroy huge parts of them. Not only is this a problem for the coral, but also a quarter of all sea creatures call the reefs home.