Stromatolites at Hamelin Pool, Shark Bay, Australia

Stromatolites at Hamelin Pool, Shark Bay, Australia

© National Aeronautics and Space Administration, JSC Astrobiology Institute.

Stromatolites are uncommon today because burrowing and grazing organisms destabilize marine sediments and consume the microbial mats produced by cyanobacteria. Exceptions occur in hyper-saline environments, like Shark Bay, where few organisms can survive.

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