Not everything died, of course. Scorpions survived, along with almost a third of critters with backbones that lived on land. Cockroaches might have, but they wouldn't show up for another hundred million years or so. I'll get back to them.
(Victor Leshyk, via Brown University press release, used w/o permission.)
Prophets of Doom
Being a prophet of doom has perks.Consistently finding the fly in the ointment; the missing nail that dooms horse, rider, and kingdom; or the sliver cloud's dark lining; may earn you a reputation for serious thinking. Or folks may get tired of listening to you. But there always seems to be a fresh audience, eager to be scared out of their wits.
Maybe that's why so many folks keep predicting the coming Apocalypse, environmental catastrophes, and economic collapse.
I like cute animals and clean air: and, being Catholic, must be concerned about social justice. (Catechism of the Catholic Church, 1928-1942)
That's real social justice, not the screwball politics of the last few decades, and that's another topic.
The Coming Ice Age, Global Warming, and All That
It's been quite a while since folks worried about the coming ice age. Global warming was fashionable for quite a while, although I gather that it's now called climate change.I don't doubt that Earth's climate is changing. That's been happening for the last four and a half billion years. Apparently now we're supposed to believe that climate shouldn't change, and it's our fault that it does.
Manure, Killer Fog, Smog, ...
There's an element of truth to the notion that humans are to blame for change. From about 1760 to 1820, we used increasingly effective machinery to raise crops and make everything from cloth to furniture.By 1883, we had a steam engine that worked as hard as 10,000 horses. We had also learned that burning coal on an industrial scale has unhealthy side effects. We improved the technology and adjusted how we live, so London isn't shrouded in a killer fog today.
About fifty years back, we learned pretty much the same thing about gasoline.
You don't hear so much about smog these days. We still drive cars here in America, but we also started controlling what sort of stuff the things produce.
The lesson to learn isn't that machinery is bad. If Londoners hadn't stopped using horses, the city would have been about nine feet deep in manure by 1900, and that's not quite another topic.
Over the last million years, we've learned how to safely use fire, sharp sticks, string, iron, and electricity. There's no evidence that we're stupider now than when we began: so I figure that we'll keep learning.
Humans: Doing Our Job
God is large and in charge.That idea is more elegantly framed in Sacred Scripture:
"Our God is in heaven; whatever God wills is done."That doesn't mean that we can sit back and let the Almighty do all the work. We've got a job, and it's a big one:
(Psalms 115:3)
"Many are the plans in a man's heart, but it is the decision of the LORD that endures."
(Proverbs 19:21)
"God blessed them, saying: 'Be fertile and multiply; fill the earth and subdue it. Have dominion over the fish of the sea, the birds of the air, and all the living things that move on the earth.' "This is not the old Victorian-era notion that nature is something for us to plunder. Our job is a bit more like that of a steward or foreman. We don't own this place.
(Genesis 1:28)
The world belongs to God. Our responsibility is taking care of it, making improvements, and passing it along to future generations. (Catechism, 339, 2292-2296, 2415-2418)
I've been over this before:
- "Designed as Stewards"
(March 17, 2013)
1. A Scorpion's Mark in the Sands of Time
(From Discovery News, via FoxNews.com, used w/o permission.)
"Photo of the rock with the imprint of what is believed to be a scorpion. (New Mexico Museum of Natural History)"
"World's oldest scorpion found""Anthropogenic climate change" means changes in Earth's climate that happened since about 1800. It's been called the coming ice age and global warming in the decades since my youth, and the more popular current term is simply "climate change." The fashionable assumption is that humans are to blame.
Larry O'Hanlon, Discover News, via FoxNews.com (November 27, 2013)
"It may not look like much, but together with other tracks in the 280 million-year-old rocks of Prehistoric Trackways National Monument in southern New Mexico, this vague form has been identified as the one and only fossil impression of a scorpion body ever found. The scorpion rested here for a time, then scurried off, and the imprint of its body eventually turned to stone.
"The age of the trace fossil, as body impressions and tracks are called, takes scorpions way back to the early Permian. That confirms that scorpions have survived a lot of gigantic mass extinction events between then and now. What's more, seeing how the carbon dioxide levels in the Permian atmosphere were probably three times what they are today on Earth, it's not likely anthropogenic climate change will stop these hardy arthropods either.
" 'We gave it the name Alacranichnus, which means scorpion trace (alacran is Spanish for scorpion and ichnos is Greek for trace),' said Spencer Lucas, curator at the New Mexico Museum of Natural History and Science...."
I think it's possible that carbon dioxide from 19th century factories, methane from belching cows, and Los Angeles smog affected Earth's climate.
But I also think it's possible that Earth's climate has changed during the last two centuries because Earth's climate has been changing for about 4,500,000,000 years: give or take a few hundred million.
It would be very odd, if this planet suddenly stopped changing.
Durability and Change
The scorpion that made that mark, some 280,000,000 years back, was not the earliest known critter of that sort.Other species of scorpions may have been among the first animals on land, about 350,000,000 years ago, and the first scorpions lived in Earth's oceans 430,000,000 or so years before we developed spears and steam engines.
Today's scorpions don't look quite like the original models, but they haven't changed all that much. Cockroaches are comparative newcomers that didn't show up until about 100,000,000 years ago, and rats have only been around for about 54,000,000 years.
We've been using fire for only 1,000,000 years, more or less, so we don't have much of a track record yet. I strongly suspect that we're nearly as durable as rats, cockroaches, and scorpions.
'All of the above' manage to live in a wide range of environments, and three are notoriously indiscriminate about what they'll eat. Scorpions are strictly meat-eaters, which may or may not be significant.
2. Acid Rain and the Great Dying
(From MIT News Office, used w/o permission.)
"A possible cause of the end-Permian mass extinction: Lemon juice?"I like undiluted lemon juice as a beverage, which may be a bit unusual, but many folks like it with their salads. It's tasty, nutritious, and can sting like — well, like lemon juice on a paper cut.
Jennifer Chu, MIT News Office (November 25, 2013)
"MIT researchers find that rain as acidic as lemon juice may have contributed to massive die-offs on land 252 million years ago.
"Rain as acidic as undiluted lemon juice may have played a part in killing off plants and organisms around the world during the most severe mass extinction in Earth's history.
"About 252 million years ago, the end of the Permian period brought about a worldwide collapse known as the Great Dying, during which a vast majority of species went extinct.
"The cause of such a massive extinction is a matter of scientific debate, centering on several potential causes, including an asteroid collision, similar to what likely killed off the dinosaurs 186 million years later; a gradual, global loss of oxygen in the oceans; and a cascade of environmental events triggered by massive volcanic eruptions in a region known today as the Siberian Traps.
"Now scientists at MIT and elsewhere have simulated this last possibility, creating global climate models of scenarios in which repeated bursts of volcanism spew gases, including sulfur, into the atmosphere. From their simulations, they found that sulfur emissions were significant enough to create widespread acid rain throughout the Northern Hemisphere, with pH levels reaching 2 — as acidic as undiluted lemon juice. They say such acidity may have been sufficient to disfigure plants and stunt their growth, contributing to their ultimate extinction...."
Acid rain enjoyed a sort of popularity a few years ago, as a dreadful environmental threat. It's produced by some industrial processes, volcanoes, and dimethylsulfide (DMS) from coccolithophores, a kind of plankton; some salt marsh fungi; and some yeasts used in home-brewed beer.
We could, in principle, abolish all industry and stop brewing beer: but DMS and "acid rain" will be around as long as Earth has plankton, fungi, yeast, or volcanoes.
Coincidence and Uncertainty
(Erik Klemetti, via Wired Science, used w/o permission.)
The Siberian Traps formed during a million years of massive volcanic activity. What's left of them today cover an area roughly the size of western Europe between today's Ural and Cherskiy mountains, and may have been twice that size before 250,000,000 years of erosion happened.
The eruptions started when the Wilkes Land anomaly and mass concentration formed. Maybe it's a coincidence that a million years of intense volcanism started then, maybe not. Most of Wilkes Land is buried under the Antarctic ice cap, which makes collecting evidence difficult.
I wouldn't be surprised if we learn that an asteroid hit Wilkes Land a quarter of a billion years back, sending shock waves through the planet. If one of Earth's biggest volcanic events 'just happened' to start on at impact's antipodal point, that's a whacking great coincidence. Something like that happened on Mercury, and that's yet another topic.
We've known about the Siberian Traps and Great Dying for years. What makes this "news" is that MIT scientists think the Permian mass extinction only took about 20,000 years.
That's what the next item is about, partly.
3. Sudden Death, Permian Style
(From unknown source, via Daily Galaxy/MIT/Science.org, used w/o permission.)
Large volcanic eruptions in Siberia, 250,000,000 years later.
" 'The Great Dying' --MIT Insights into the Most Severe Mass Extinction in Earth's History"An asteroid impact may be "an unlikely option" in the Daily Galaxy/MIT/Science.org writer's opinion, but the last I checked it was still being considered by at least some scientists.
Daily Galaxy via MIT and Science.org (blog) (November 24, 2013)
"It was the greatest extinction event of all time (at least by Earth standards): Since the first organisms appeared on Earth approximately 3.8 billion years ago, life on the planet has had some close calls. In the last 500 million years, Earth has undergone five mass extinctions, including the event 66 million years ago that wiped out the dinosaurs. And while most scientists agree that a giant asteroid was responsible for that extinction, there's much less consensus on what caused an even more devastating extinction, the end-Permian extinction, that occurred 252.2 million years ago, decimating 90 percent of marine and terrestrial species, from snails and small crustaceans to early forms of lizards and amphibians. 'The Great Dying,' as it's now known, was the most severe mass extinction in Earth's history, and is probably the closest life has come to being completely extinguished. Possible causes include immense volcanic eruptions, rapid depletion of oxygen in the oceans, and — an unlikely option — an asteroid collision.
"While the causes of this global catastrophe are unknown, an MIT-led team of researchers established in 2011 that the end-Permian extinction was extremely rapid, triggering massive die-outs both in the oceans and on land in less than 20,000 years — the blink of an eye in geologic time. The MIT team also found that this time period coincides with a massive buildup of atmospheric carbon dioxide, which likely triggered the simultaneous collapse of species in the oceans and on land...."
We don't seem to know exactly what set off the Siberian Traps eruptions. Something big hitting at exactly the right, or wrong, time and place might have at least helped trigger them. Then again, maybe not.
MIT scientists found that carbon dioxide levels before the Great Dying rose a little less quickly then they have since we started burning fossil fuels on industrial scales. This increase went on for tens of thousands of years at the end of the Permian, and may have had something to do with the mass extinction.
We've been burning fossil fuels for about one tenth as long. I'm rather dubious that we'll be using the same energy source in the year 12013 or 22013. For one thing, we'll probably run out of coal and oil long before then.
Still, if we keep killing buffalo and eroding mountainsides and cutting down forests the way folks did in the 1800s - - - come to think of it, we stopped doing all that rather early in the 1900s, and that's almost a hundred years back now.
I'm as concerned about Earth as anyone else. I live here, and want my kids to have a decent place to call home. But I've become weary of fascinating research being shackled to conventional hand-wringing about the crisis du jure.
Science and Sherlock Holmes
On a happier note, since it looks like it only took about 20,000 years for the worst of the end-of-Permian mass extinction to run its course, whatever caused it had to work fast. That narrows the field for theories explaining Earth's biggest mass extinction: considerably.Part of solving mysteries, fictional and otherwise, can be showing that some explanations cannot be true:
"How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?"Related posts:
(Sherlock Holmes, "The Sign of the Four")
- Change
- "Oxygen, Ice, and Our Changing Earth"
(August 30, 2013)
Particularly - "Vast and Ancient"
(February 27, 2013)
Particularly - "Taking Life a Thousand Years at a Time"
(June 10, 2012) - " 'In a State of Journeying' "
(January 18, 2012) - "Climate Changes: So What Else is New?"
(May 16, 2011)
- "Oxygen, Ice, and Our Changing Earth"
- The big picture
- "Earth's Grander Canyon, a Submerged Mountain, and an Ancient Ice Sheet"
(September 13, 2013)
Particularly - "Freedom, Fear, Mayan 'Doomsday,' and a Solar Super-Flare (Maybe)"
(November 30, 2012)
Particularly - "Fasting, Penance: and Infinite Depths of Joy"
(June 3, 2012)
Particularly - "Hope, Joy, and 'More Despondent Than Thou?' "
(January 8, 2012)
Particularly - "
ArchaeologyPaleontology, Science, and Wishful Thinking"
(October 12, 2010)
Particularly
- "Earth's Grander Canyon, a Submerged Mountain, and an Ancient Ice Sheet"
2 comments:
Wrong article form: "as an dreadful environmental threat."
The Friendly Neighborhood Proofreader
Brigid,
Found, fixed, thanks!
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