When the stromatolites were discovered by scientists in 1956, they were the first ever recorded living examples of structures previously found only as fossils in ancient rocks. Although Shark Bay’s stromatolites are just 2,000 – 3,000 years old, the cyanobacteria that build them are similar to life forms found on Earth up to 3.5 billion years ago! This means the stromatolites are modern-day examples of life in Precambrian times.