Search results
Results from the WOW.Com Content Network
The Boring Billion ended during the Neoproterozoic period with a significant increase in photosynthetic activities, causing oxygen levels to rise 10- to 20-fold to about one-tenth of the modern level. This rise in oxygen concentration, known as the Neoproterozoic oxygenation event or "Second Great Oxygenation Event", was likely caused by the ...
The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [2] was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. [3]
Carboniferous is the period during which both terrestrial animal and land plant life was well established. [10] Stegocephalia (four-limbed vertebrates including true tetrapods), whose forerunners (tetrapodomorphs) had evolved from lobe-finned fish during the preceding Devonian period, became pentadactylous during the Carboniferous. [11]
The following time span was the Phanerozoic eon, during which oxygen-breathing metazoan life forms began to appear. The amount of oxygen in the atmosphere has fluctuated over the last 600 million years, reaching a peak of 35% [23] during the Carboniferous period, significantly higher than today's 21%.
The Neoproterozoic Oxygenation Event (NOE), also called the Second Great Oxidation Event, was a geologic time interval between around 850 and 540 million years ago during the Neoproterozoic era, which saw a very significant increase in oxygen levels in Earth's atmosphere and oceans. [2]
Eventually all surface reductants (particularly ferrous iron, sulfur and atmospheric methane) were exhausted, and the atmospheric free oxygen levels soared permanently during the Siderian and Rhyacian periods in an aerochemical event called the Great Oxidation Event, which brought atmospheric oxygen from near none to up to 10% of the modern ...
Carboniferous rainforest collapse is sometimes treated as an extinction factor for large Carboniferous arthropods such as giant griffinfly Meganeura and millipede Arthropleura. It is common theory that high oxygen levels have led to larger arthropods, and these organisms have been thought to live in forests.
The term primarily refers to a major extinction, the Kellwasser event, also known as the Frasnian-Famennian extinction, [1] which occurred around 372 million years ago, at the boundary between the Frasnian age and the Famennian age, the last age in the Devonian Period. [2] [3] [4] Overall, 19% of all families and 50% of all genera became ...