Pristine coral reef discovered off Tahiti
A research mission, led by UNESCO, found the reef, which stretches for nearly three kilometres and exists at depths down to 70m (230ft). This is around the ocean's "twilight zone," where there is just enough light to sustain life, and below which the ocean transitions into a dark abyss.
The reef probably took around 25 years to grow. Some of the rose-shaped corals measure more than two metres in diameter. This is highly unusual because, up to now, the vast majority of the world’s known coral reefs sit at depths of up to 25m.