‘A bad time to be alive’: Mass extinction 444 million years ago linked to loss of oxygen in Earth’s oceans
‘By expanding our thinking of how oceans behaved in the past, we could gain some insights into oceans today,’ says scientist at Stanford University
Peter Stubley
Tuesday 14 April 2020 11:33
The first major mass extinction in Earth’s history was linked to a severe and prolonged lack of oxygen in the oceans, according to a new study which could help scientists understand modern climate change.
Some 85 per cent of all species perished during the Late Ordovician die-off about 444 million years ago – a time when the vast majority of life was marine-based and most of our present day continents formed a single land mass, Pangaea.
A first wave of extinctions was caused by global cooling. When that ice age ended, sea levels rose and oxygen levels plummeted, resulting in a deficiency of oxygen, or anoxia.
In a new study, researchers at Stanford University found evidence that these anoxic conditions lasted for more than three million years – significantly longer than similar extinction events.
“For most ocean life, it was indeed a really bad time to be alive,” said co-author Erik Sperling, an assistant professor of geological sciences at Stanford University.
The study, published in Nature Communications, examined the geological record on the boundary between the Hirnantian and Rhuddanian ages in an attempt to bolster the theory.
A new model was created by Richard George Stockey, a graduate student at Stanford Earth, to incorporate previously published metal isotope data as well as new data from samples of black shale from the Murzuq Basin in Libya.
Taking into account 31 different variables, including the amounts of uranium and molybdenum that settle on the sea floor, it concluded that severe and prolonged ocean anoxia must have occurred across large volumes of Earth’s oceans.
“We can confidently say a long and profound global anoxic event is linked to the second pulse of mass extinction in the Late Ordovician,” said Mr Sperling.
The researchers said the findings have relevance for today given that global climate change is contributing to declining oxygen levels in the open ocean and coastal waters.
Last December, another study found that the overall level of oxygen in the oceans has dropped by roughly 2 per cent, while the number of known hypoxic “dead zones” has skyrocketed from 45 known sites in the 1960s to at least 700 areas today, some encompassing thousands of square miles.
“We actually have a big problem modelling oxygenation in the modern ocean,” Mr Sperling said. “And by expanding our thinking of how oceans have behaved in the past, we could gain some insights into the oceans today.”
Mr Stockey, whose research was supported by the Alfred P Sloan Foundation, National Science Foundation, Packard Foundation and Nasa, added: “There is no way that low oxygen conditions are not going to have a severe effect on diversity.”
Lack of oxygen in the oceans may also have played a part in the Devonian mass extinction 375 million years ago.
The most famous mass extinction is the Cretaceous-Paleogene event that wiped out all non-avian dinosaurs some 65 million years ago as a result of an asteroid strike that acidified the planet’s oceans.
Poster Comment:
Trilobites and Tully Monsters are a couple of the fossils I learned about as a young man studying about the past and rocks, geology and minerology.
#1: StraitGate To: BTP Holdings (#0)
Couldn't have been too much worse than it is today.
StraitGate posted on 2020-04-23 22:10:42 Reply Private Reply
#2: BTP Holdings To: StraitGate (#1)
I doubt the Caveman could be in the same boat as the rest of us are today.
Someone that specializes in the study of fossils is called a paleontologist. ;)
BTP Holdings posted on 2020-04-24 03:23:27 Reply Private Reply
#3: randge To: BTP Holdings (#0)
But the authors get bto sneak in the words "climate change" so that makes it acceptable to publish in a major outlet.
randge posted on 2020-04-24 07:52:01 Reply Private Reply
#4: BTP Holdings To: randge (#3)
Yes this is true.
But when they uncovered Wooly Mammoths that were frozen in glaciers they still had undigested food in their stomachs. This indicates they were flash frozen. What sort of catastrophe would cause that to occur? ;)
BTP Holdings posted on 2020-04-24 07:57:57 Reply Private Reply
#5: Lod To: randge (#3)
This article is useless.
444M years ago, are you shitting me?
Lod posted on 2020-04-24 08:17:30 Reply Private Reply
#6: BTP Holdings To: Lod (#5)
Geologic time periods leave the mind numb since it is hard to wrap the mind around time that stretches so far back. ;)
BTP Holdings posted on 2020-04-24 08:44:33 Reply Private Reply
#7: randge To: BTP Holdings (#4)
That's controversial to say the least.
It's an aspect of the disappearance of megafauna (creatures, mammals of > 100 lbs.) twelve millenia ago at the beginning of the Holocene Epoch - the modern period on the big stratgraphic chart.
They're talking about a flash freeze that occured in the wake of some cataclysm: a comet, a solar flare, even mass vulcanism. Some geologists even dispute catastrophe at this point in time at all. It is a hard thing to get your head around since there are so many biological, geological and even astrophysical processes to take into consideration.
For a starting point, there is a good article on this topic here with interesting videos featuring discussion by Randall Carlson and Graham Hancock.
sacredgeometryinternation...uck-mammoths-extinctions- alaska-scene-giant-cataclysm-end-ice-age/
randge posted on 2020-04-24 09:49:30 Reply Private Reply
#8: BTP Holdings To: randge (#7)
I have no difficulty wrapping my mind aroud any of it.
Thanks for your input. ;)
BTW, my illness only affected my short term memory.
BTP Holdings posted on 2020-04-24 09:53:55 Reply Private Reply
#9: randge To: BTP Holdings (#8)
You have a big head, Old Paint. :- O
randge posted on 2020-04-24 10:35:30 Reply Private Reply
#10: BTP Holdings To: randge (#9)
We worked a concert at the Aragon Ballroom in Chicago. The name of the headline act was Big Head Todd.
They were selling a T-shirt with a girl on it. She was thinking, "Big head, Hmmmm" LOL
BTP Holdings posted on 2020-04-24 11:01:39 Reply Private Reply
#11: NeoconsNailed To: BTP Holdings (#0)
Wow, tully monsters -- looks like a bionic submarine with two antennae for guidance!
en.wikipedia.org/ wiki/Tullimonstrum
NeoconsNailed posted on 2020-04-24 11:17:55 Reply Private Reply
#12: NeoconsNailed To: randge (#7)
NeoconsNailed posted on 2020-04-24 11:22:24 Reply Private Reply
#13: randge To: NeoconsNailed (#12)
Lookit the windows in ancient cathedrals like Notre Dame in Paris.
Follow the structure of things man-made or occurring in nature like the petals on a flower, the growth of a pineapple or the development of a mollusk and how they express the Fibonacci series and the Golden Mean.
randge posted on 2020-04-24 12:30:12 Reply Private Reply
#14: NeoconsNailed To: randge (#13)
NeoconsNailed posted on 2020-04-24 12:37:35 Reply Private Reply
#15: BTP Holdings To: NeoconsNailed (#11)
Those were found in Pennsylvania limestone formations in rock quarries in the Mid West. I knew of a few people who had some great collections of fossils. ;)
BTP Holdings posted on 2020-04-24 14:12:20 Reply Private Reply
#16: randge To: NeoconsNailed (#14)
randge posted on 2020-04-24 14:25:23 Reply Private Reply
#17: NeoconsNailed To: randge (#16)
NeoconsNailed posted on 2020-04-24 14:37:06 Reply Private Reply
#18: randge To: NeoconsNailed (#17)
The world is never all quite what you think it is. There's always something new out there to challenge your imagination.
"And therefore as a stranger give it welcome. There are more things in heaven and earth, Horatio, Than are dreamt of in your philosophy."
randge posted on 2020-04-24 15:22:42 Reply Private Reply
#19: Anthem To: BTP Holdings (#0)
This is true, because I'm going to choke the shit outta anybody who thinks they have more rights than me because "diversity".
Anthem posted on 2020-04-24 15:47:27 Reply Private Reply
#20: Anthem To: BTP Holdings (#2)
Yeah, that's a waycist profession. They need more duskyontologists.
Anthem posted on 2020-04-24 15:50:14 Reply Private Reply
#21: BTP Holdings To: Anthem (#20)
I'm sort of paleo myself, but I have never heard of that word before. ;)
BTP Holdings posted on 2020-04-24 15:53:44 Reply Private Reply
#22: NeoconsNailed To: randge (#18)
NeoconsNailed posted on 2020-04-24 16:06:48 Reply Private Reply
#23: Anthem To: BTP Holdings (#4)
An asteroid sized meteorite (6 mi in diameter) flew over North America descending at a 30 degree angle and hit in the Atlantic, shoving the tectonic plate under Europe 2,000 miles north away from the equator. With a 2 degree change in Earth's axis of rotation, and the skies blackened with a mixture of ash, vaporized water, and other stuff, the freeze of the displaced tundra and its wildlife happened in a matter of hours.
www.youtube.com/watch?v=Ys4Uq46OyZs Art Bell, audio only. I have this book.
Anthem posted on 2020-04-24 16:09:29 Reply Private Reply
#24: randge To: NeoconsNailed (#22)
randge posted on 2020-04-24 17:42:18 Reply Private Reply
#25: NeoconsNailed To: randge (#24)
NeoconsNailed posted on 2020-04-24 17:51:00 Reply Private Reply