The flowers of the sea are actually animals
The world’s coral reefs provide some of the most spectacular natural colour on the planet. Despite an appearance of simplicity, the tiny individuals that make up those reefs are some of the most complex in the living world.
While often referred to as the ‘rainforest of the ocean’, corals are actually animals, not plants. But much of their colour comes from the algae (not plants either, strictly speaking) that live in a remarkable symbiotic (‘living together’) relationship with them.
An individual coral is known as a polyp, a soft organism comprising a base, a hollow gastro-vascular (‘stomach-vessel’) tube, and a mouth opening surrounded by tiny tentacles.
Each polyp is hermaphrodite (i.e. having both male and female sexual organs). There are two types of sexual reproduction in coral. In ‘brooder’ corals, the egg is fertilized within the polyp, incubated and then later released into the ocean. In externally fertilizing corals, some polyps release sperm, others eggs. In the awesome phenomenon known as mass coral spawning, all the corals in one geographic region release their eggs/sperm on the same night, all synchronized by the phases of the moon.