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The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes. Researchers have identified five other major extinction events in Earth's history, with estimated losses below: [11] End Ordovician: 440 million years ago, 86% of all species lost, including graptolites
This began approximately 2.460–2.426 Ga (billion years) ago during the Siderian period and ended approximately 2.060 Ga ago during the Rhyacian. [4]
Photosynthetic organisms appeared between 3.2 and 2.4 billion years ago and began enriching the atmosphere with oxygen. Life remained mostly small and microscopic until about 580 million years ago, when complex multicellular life arose, developed over time, and culminated in the Cambrian Explosion about 538.8 million years ago. This sudden ...
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 Huronian glaciation (or Makganyene glaciation) [1] was a period where at least three ice ages occurred during the deposition of the Huronian Supergroup. Deposition of this largely sedimentary succession extended from approximately 2.5 to 2.2 billion years ago (), during the Siderian and Rhyacian periods of the Paleoproterozoic era.
A new study reveals that all life on earth was obliterated two billion years ago, and the problem was oxygen. Samples of Canadian mineral show almost all life was wiped out 2 billion years ago ...
About 2.1 billion years ago, a blob-like creature inched along on an early Earth. As the organism moved, it carved out tunnels, which may be the earliest evidence of a moving critter on the planet ...
Until roughly 2.3 billion years ago, oxygen was probably only 1% to 2% of its current level. [9]: 323 The banded iron formations, which provide most of the world's iron ore, are one mark of that mineral sink process. Their accumulation ceased after 1.9 billion years ago, after the iron in the oceans had all been oxidized. [9]: 324