Attention Deficit Disorder Prosthetic Memory Program

Snowball Earth

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Snowball Earth - © Attention Deficit Disorder Prosthetic Memory Program

The Snowball Earth hypothesis proposes that during one or more of Earth’s icehouse climates, Earth’s surface became entirely or nearly entirely frozen, sometime earlier than 650 Mya (million years ago) during the Cryogenian period. Proponents of the hypothesis argue that it best explains sedimentary deposits generally regarded as of glacial origin at tropical palaeolatitudes and other enigmatic features in the geological record. Opponents of the hypothesis contest the implications of the geological evidence for global glaciation and the geophysical feasibility of an ice- or slush-covered ocean and emphasize the difficulty of escaping an all-frozen condition. A number of unanswered questions remain, including whether the Earth was a full snowball, or a “slushball” with a thin equatorial band of open (or seasonally open) water.

The snowball-Earth episodes are proposed to have occurred before the sudden radiation of multicellular bioforms known as the Cambrian explosion. The most recent snowball episode may have triggered the evolution of multicellularity. Another, much earlier and longer snowball episode, the Huronian glaciation, which would have occurred 2400 to 2100 Mya, may have been triggered by the first appearance of oxygen in the atmosphere, the “Great Oxygenation Event”.

World's First Photograph - © Attention Deficit Disorder Prosthetic Memory Program
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World's First Photograph
Large Hadron Collider - © Attention Deficit Disorder Prosthetic Memory Program
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Large Hadron Collider
Drone Hunting Eagles - © Attention Deficit Disorder Prosthetic Memory Program
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Drone Hunting Eagles
French Punk Demo Tapes (1987-1997) - © Attention Deficit Disorder Prosthetic Memory Program
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French Punk Demo Tapes (1987-1997)
Bioluminescent Bacteria - © Attention Deficit Disorder Prosthetic Memory Program
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Bioluminescent Bacteria
Goûter Refuge - © Attention Deficit Disorder Prosthetic Memory Program
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Goûter Refuge
Sea Org Contract - © Attention Deficit Disorder Prosthetic Memory Program
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Sea Org Contract
Interchanges - © Attention Deficit Disorder Prosthetic Memory Program
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Interchanges
Peter Cain's Cars painting series - © Attention Deficit Disorder Prosthetic Memory Program
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Peter Cain's Cars painting series
Zodiak Free Arts Lab - © Attention Deficit Disorder Prosthetic Memory Program
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Zodiak Free Arts Lab
Animal Chimera - © Attention Deficit Disorder Prosthetic Memory Program
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Animal Chimera
Grackles Invade Walmart Parking Lot - © Attention Deficit Disorder Prosthetic Memory Program
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Grackles Invade Walmart Parking Lot

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