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I.e. all of North America and much of South burned down, 30+ genera extinct, and the Clovis culture obliterated, right around 12,800ya. They have actually ident

I.e. all of North America and much of South burned down, 30+ genera extinct, and the Clovis culture obliterated, right around 12,800ya. They have actually identified the exact year from ice cores.

adolph 3y ago
Younger Dryas Impact Theory? https://en.wikipedia.org/wiki/Younger_Dryas https://en.wikipedia.org/wiki/Younger_Dryas The Younger Dryas, which occurred circa 12,900 to 11,700 years BP,[2] was a return to glacial conditions which temporarily reversed the gradual climatic warming after the Last Glacial Maximum (LGM),[3] which lasted from circa 27,000 to 20,000 years BP. The Younger Dryas was the last stage of the Pleistocene epoch that spanned from 2,580,000 to 11,700 years BP and it preceded the current, warmer Holocene epoch.
- angiosperm 3y ago
  It is common to assume the comet strike kicked off the Younger Dryas cold spell, but it could still have been a coincidence. There were other cold spells like it in previous interglacials, and we don't know what caused those. Those might also have been caused by comet strikes; it took us long enough to identify this one. What happens that takes a thousand years to clear up is another mystery on the pile. We know with certainty there was a comet strike, about the right time, that caused serious havoc, but evidence that it changed the climate is harder to establish. Firm evidence of sharply falling global temperature before the strike would settle the question. If the strike really did precede the cold spell, it may be hard to prove causation. It seems like the way to bet. Another mystery is how the conflagration spared (just) bison, moose, deer, elk, pronghorn, and grizzly and brown bears.
  - mistrial9 3y ago
    those animals run pretty well .. where is there more information on this ecological / ecosystem impacts part... species names and such ? forests too ?
    - angiosperm 3y ago
      Look up Pleistocene-Holocene boundary extinctions. AFAIK there were not plant extinctions coincident with the animal extinctions.

I.e. all of North America and much of South burned down, 30+ genera extinct, and the Clovis culture obliterated, right around 12,800ya. They have actually identified the exact year from ice cores.

adolph 3y ago

Younger Dryas Impact Theory? https://en.wikipedia.org/wiki/Younger_Dryas https://en.wikipedia.org/wiki/Younger_Dryas The Younger Dryas, which occurred circa 12,900 to 11,700 years BP,[2] was a return to glacial conditions which temporarily reversed the gradual climatic warming after the Last Glacial Maximum (LGM),[3] which lasted from circa 27,000 to 20,000 years BP. The Younger Dryas was the last stage of the Pleistocene epoch that spanned from 2,580,000 to 11,700 years BP and it preceded the current, warmer Holocene epoch.

angiosperm 3y ago
It is common to assume the comet strike kicked off the Younger Dryas cold spell, but it could still have been a coincidence. There were other cold spells like it in previous interglacials, and we don't know what caused those. Those might also have been caused by comet strikes; it took us long enough to identify this one. What happens that takes a thousand years to clear up is another mystery on the pile. We know with certainty there was a comet strike, about the right time, that caused serious havoc, but evidence that it changed the climate is harder to establish. Firm evidence of sharply falling global temperature before the strike would settle the question. If the strike really did precede the cold spell, it may be hard to prove causation. It seems like the way to bet. Another mystery is how the conflagration spared (just) bison, moose, deer, elk, pronghorn, and grizzly and brown bears.
- mistrial9 3y ago
  those animals run pretty well .. where is there more information on this ecological / ecosystem impacts part... species names and such ? forests too ?
  - angiosperm 3y ago
    Look up Pleistocene-Holocene boundary extinctions. AFAIK there were not plant extinctions coincident with the animal extinctions.