These are preserved examples of what are called stromatolites. They are created when many millimetre-scale layers of bacteria and sediment build up over time into larger, dome-like forms.

The light colour of the water is the first clue that Gutharragudu is special. Zoe Kean searching for stromatolites at Gutharragudu/Shark Bay in Western Australia, a place where red desert sand ...

As Earth cools, a crust forms over it. Mounded bacterial formations called stromatolites appear in shallow waters of the early oceans, and small land blocks collide with one another to produce the ...