Cyanobacteria built stromatolites in Hamelin Pool at Shark Bay World Heritage Area. Area contains submerged stromatolites like the ones built by cyanobacteria 3.5 billion years ago. Cyanobacteria are believed to be the bacteria that added oxygen to Earth’s oceans and atmosphere, making it possible for oxygen-breathing, complex life forms to live on Earth – including us. The water in Hamelin Pool is twice as salty as water in the open ocean! Animals that would normally graze on algae, such as chitons and snails, cannot survive in these conditions. Hamelin Pool in Shark Bay has the most diverse and abundant examples of living marine stromatolites in the world.

More info available at Sharkbay.org