4 ms·

Is it? The current extinction event seems to be faster, and we're far from done.

Ancalagon 7y ago
I don't actually think it is faster is it? The KT event deposited a lot of meteoric material over a few decades but I was under the impression that most of the species that went extinct actually died off in the first few years (due to the sun being blocked by dust).
- rebuilder 7y ago
  This probably requires a fairly nuanced analysis. A quick googling suggests a low estimate for the duration of the K-T event to be about 1000 years.
mc32 7y ago
Of course it's all estimates and they are getting more granular and coarsely precise with new discoveries and techniques. The Smithsonian Mag has this[1] to say: >“The climate impact was enormous,” Robertson says. “Dust and soot from the impact and fires would have created an ‘impact winter’ with zero sunlight reaching the surface of the Earth for a year or so.” >"Organisms that had somehow managed to survive the intense heat and fires now faced a new threat. “Loss of sunlight would have eliminated the phytoplankton base of almost all aquatic food chains and caused complete collapse of aquatic ecosystems,” ... All told, what evolution took over 180 million years to build up could have been cut back in less than the lifetime of an individual Tyrannosaurus rex. Death came quickly at the end of the Cretaceous." >"... Pollen and plankton, Robertson points out, actually provide a more refined picture of what happened in the wake of the impact. Nevertheless, the available fossil record shows that about 75 percent of known species completely disappeared, and things probably weren’t rosy for the survivors. “It’s is reasonable to suppose that the 25 percent of surviving species had near-total mortality,” ...but these fortunate organisms were the ones that would go on to set the stage for the next 66 million years of evolutionary history." [1[]https://www.smithsonianmag.com/science-nature/what-happened-seconds-hours-weeks-after-dino-killing-asteroid-hit-earth-180960032/ https://www.smithsonianmag.com/science-nature/what-happened-...

I don't actually think it is faster is it? The KT event deposited a lot of meteoric material over a few decades but I was under the impression that most of the species that went extinct actually died off in the first few years (due to the sun being blocked by dust).

rebuilder 7y ago
This probably requires a fairly nuanced analysis. A quick googling suggests a low estimate for the duration of the K-T event to be about 1000 years.

mc32 7y ago

Of course it's all estimates and they are getting more granular and coarsely precise with new discoveries and techniques. The Smithsonian Mag has this[1] to say: >“The climate impact was enormous,” Robertson says. “Dust and soot from the impact and fires would have created an ‘impact winter’ with zero sunlight reaching the surface of the Earth for a year or so.” >"Organisms that had somehow managed to survive the intense heat and fires now faced a new threat. “Loss of sunlight would have eliminated the phytoplankton base of almost all aquatic food chains and caused complete collapse of aquatic ecosystems,” ... All told, what evolution took over 180 million years to build up could have been cut back in less than the lifetime of an individual Tyrannosaurus rex. Death came quickly at the end of the Cretaceous." >"... Pollen and plankton, Robertson points out, actually provide a more refined picture of what happened in the wake of the impact. Nevertheless, the available fossil record shows that about 75 percent of known species completely disappeared, and things probably weren’t rosy for the survivors. “It’s is reasonable to suppose that the 25 percent of surviving species had near-total mortality,” ...but these fortunate organisms were the ones that would go on to set the stage for the next 66 million years of evolutionary history." [1[]https://www.smithsonianmag.com/science-nature/what-happened-seconds-hours-weeks-after-dino-killing-asteroid-hit-earth-180960032/ https://www.smithsonianmag.com/science-nature/what-happened-...