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The timeline of the evolutionary history of life represents the current scientific theory outlining the major events during the development of life on planet Earth. Dates in this article are consensus estimates based on scientific evidence , mainly fossils .
The phosphorus cycle is the biogeochemical cycle that involves the movement of phosphorus through the lithosphere, hydrosphere, and biosphere.Unlike many other biogeochemical cycles, the atmosphere does not play a significant role in the movement of phosphorus, because phosphorus and phosphorus-based materials do not enter the gaseous phase readily, [1] as the main source of gaseous phosphorus ...
Phosphorus is an essential macromineral for plants, which is studied extensively in edaphology to understand plant uptake from soil systems. Phosphorus is a limiting factor in many ecosystems; that is, the scarcity of phosphorus limits the rate of organism growth.
These timelines of world history detail recorded events since the creation of writing roughly 5000 years ago to the present day. For events from c. 3200 BC – c. 500 see: Timeline of ancient history; For events from c. 500 – c. 1499, see: Timeline of post-classical history; For events from c. 1500, see: Timelines of modern history
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
The Phosphoria includes phosphorite beds that are an important source of phosphorus. [5] Many of its shales are rich in organic matter and are petroleum source rocks , [ 6 ] and some of its dolomites include petroleum reservoirs .
Only in later editions of his works did Darwin used the term "evolution." 1858 – Rudolf Virchow proposed that cells can only arise from pre-existing cells; "Omnis cellula e celulla," all cell from cells. The Cell Theory states that all organisms are composed of cells (Schleiden and Schwann), and cells can only come from other cells (Virchow).
Phosphorus comprises 0.1% by mass of the average rock [12] (while, for perspective, its typical concentration in vegetation is 0.03% to 0.2%), [13] and consequently there are quadrillions of tons of phosphorus in Earth's 3×10 19-ton crust, [14] albeit at predominantly lower concentration than the deposits counted as reserves, which are ...