Our original plan was to take a photo shoot of the stromatolites at Hamlin's Pool. As it turns out, the organisms are extremely delicate and in no case can someone walk upon them. Before we could be disappointed, we found interesting rocks in Kalbarri which looked pretty similar to stromatolites. Not only could we take our pictures, but do it without hurting nature too.
The stromatolites in Hamelin Pool were discovered by surveyors working for an oil exploration company in 1956 and were the first living examples of structures built by cyanobacteria.
The cyanobacteria living in Hamelin Pool are direct descendants of the oldest form of photosynthetic life on earth.
The cyanobacteria live in communities on the sea bed at densities of 3000 million individuals per square metre. They are the simplest life forms to use photosynthesis to provide food and oxygen. They provided the early Earth with most of its oxygen atmosphere billions of years before plants appeared. Very fine particles of solids i.e. sand, crushed shell etc. are trapped by the sticky bacteria, to become cemented with calcium carbonate produced by the bacteria, thereby building up the stromatolite structures. Some structures are pillars up to 1.5 metres (5 ft) high and have taken thousands of years to grow. In the Marble Bar area of Western Australia there are fossil stromatolites approximately 50 metres high and 30 metres diameter. These are estimated to be over 3 billion years old. Typical growth is about 0.5 mm per year. |