Stromatolites
3,000 years ago microbes started building up stromatolites in Hamelin Pool in the south of the bay. These structures are the earliest signs of life on Earth, with some fossilized ones being found from 3,500 million years ago (though the biological origin of these fossils is disputed) at North Pole, also in Western Australia, and are considered the longest continuing biological lineage. They were first identified in 1956 here in Hamelin Pool as a living species, before that only being known in the fossil record, so they are living fossils. Hamelin Pool contains the most diverse and abundant examples of living stromatolite forms in the world. It is now hypothesized that some of these stromatolites contain a new form of chlorophyll, chlorophyll f.
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