And suddenly, we're reminded that there's so much more to the world than what we know. Turns out the Amazon, home to freaks of nature like pink dolphins and piranhas, is also hiding a gigantic coral reef that's 120-metres deep in parts, and home to over 60 species of sponges and 73 species of colourful (and many carnivorous) reef fish.

The reef is situated at the mouth of the Amazon and stretches from French Guiana to Brazil's Maranhao state. It's hidden beneath the muddy, sediment-filled waters where the Amazon meets the sea, where scientists wouldn't have thought it possible to find a thriving coral system.

A secret coral reef has been discovered in the Amazon

The discovery has shocked the scientific community, especially because it's already in danger of destruction - the Brazilian government has unwittingly sold large expanses to oil companies and drilling has already begun. 

A secret coral reef has been discovered in the Amazon