Stromatolites pump oxygen into the early atmosphere.
Stromatolites are one of the longest living forms of life on this planet. They can be traced back 3.5 billion years to the early Archean eon (Awaramik and Sprinkle, 1999). Stromatolites are sedimentary structures produced by the sediment trapping, binding, and precipitating activity of phototrophic microbes. In the case of stromatolites, these phototrophic microbes include cyanobacteria/blue-green algae (McNamara and Awaramik, 1992). The marine stromatolite communities occur mostly in hypersaline subtidal to supertidal settings Photosynthesis is the only major source of free oxygen gas in the atmosphere. As stromatolites became more common 2.5 billion years ago, they gradually changed the Earth's atmosphere from a carbon dioxide-rich mixture to the present-day oxygen-rich atmosphere. Surface is covered by a felt of cyanobacterial filaments that trap sediment grains that are washed across the mat surface. Abundant sediment supply produces granular laminae, low sediment supply produces layers rich in organic matter (green in drawing). The cyanobacteria have an extensive fossil record. The oldest known fossils, in fact, are cyanobacteria from Archaean rocks of western Australia, dated 3.5 billion years old. This may be somewhat surprising, since the oldest rocks are only a little older: 3.8 billion years old!  Early bacterial life introduced oxygen to the atmosphere. As the first free oxygen was released through photosynthesis by cyanobacteria, it was initially soaked up by iron dissolved in the oceans and formed red coloured iron oxide, which settled to the ocean floor. Early life affected the structure of the planet. Presenter Aubrey Manning and geologist Professor Maarten De Wit investigate iron rich rocks known as banded iron formations, which formed when stromatolites, some of the earliest known life forms on Earth, produced oxygen that combined with iron dissolved in the oceans. Cyanobacteria and Oxygen. Stromatolites are created by cyanobacteria, also called blue-green algae. These microscopic life forms are not really algae at all but bacteria that have the ability to carry out photosynthesis. It is the process of photosynthesis combined with the growth of the cyanobacteria that creates the distinctive dome-shaped, finely layered rocks we call stromatolites. This was transformed because cyanobacteria could photosynthesize to make its food. The process of photosynthesis uses carbon dioxide and produces oxygen as a byproduct. Billions of cyanobacteria producing oxygen, constantly, over many millions of years made an atmosphere that could support life as we know it. They were originally formed by the growth of layer upon layer of cyanobacteria, a single-celled photosynthesizing microbe that lives today in a wide range of environments ranging from the shallow shelf to lakes, rivers, and even soils. Surface is covered by a felt of cyanobacterial filaments that trap sediment grains that are washed across the mat surface. Abundant sediment supply produces granular laminae, low sediment supply produces layers rich in organic matter (green in drawing). In the hyper-saline water of Hamelin Pool at the base of Shark Bay in W.A. the rocks aren't quite what the appear to be. They are living things, Stromatolites, which are the oldest living organisms on the planet. Some scientists believe they were the first living things on mother earth. Most living animals, which feed on the bacteria and algae of which stromatolites are composed, cannot tolerate such saline conditions. As a result stromatolites can grow here successfully, undisturbed. Most stromatolites are extremely slow growing. When stromatolites first appeared on earth about 3.5 billion years ago there was little or no oxygen in the atmosphere. It was through the oxygen-generating activity of stromatolites that other animal life on earth was able to develop. Most living animals, which feed on the bacteria and algae of which stromatolites are composed, cannot tolerate such saline conditions. As a result stromatolites can grow here successfully, undisturbed. Most stromatolites are extremely slow growing. play Oxygen enters the atmosphere. Stromatolites pump oxygen into the early atmosphere. Dr Iain Stewart explains how stromatolites, one of the earliest forms of life, first released oxygen over three billion years ago when they turned sunlight into energy. Oxygen was initially soaked up by iron in the seas but eventually entered the atmosphere. Early life affected the structure of the planet. Presenter Aubrey Manning and geologist Professor Maarten De Wit investigate iron rich rocks known as banded iron formations, which formed when stromatolites, some of the earliest known life forms on Earth, produced oxygen that combined with iron dissolved in the oceans. Stromatolites are among the world's oldest fossils, some of which are over 3.5 billion years old. Stromatolites are structures formed by huge colonies of cyanobacteria, formerly called blue green algae, which contributed directly to the formation of the Earth's atmosphere and its currently habitable state. Stromatolites are formed by prokaryotic cyanobacteria, which have cells lacking a distinct nucleus. Prokaryotic bacteria are considered by some scientists to be the oldest and most primitive life form on Earth, with a well established fossil record stretching back for millions of years.
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how are stromatolites are related to oxygen'