Approximately one new species of dinosaur (representing many individual fossils) is described every week. We are living in the "golden age of dinosaur discovery", today.
Total thermonuclear war would leave a long radionuclide record, one that today's nuclear scientists could forensically walk reactions back and wonder where all the tritium and plutonium must've come from.
A fission war might leave a signal. Whether it'd still be detectable after dispersal over several vertical cm by bioturbation by recovering organisms a quarter million years after the bombs stopped falling is a different question, and far less clear to me.
Tritium would be effectively undetectable after 13000 years. Plutonium would be severely attenuated after a quarter million. Half lives do mean something. It might seem a long time to you, but it's peanuts geologically. Yes, we detected the shenanigans at Oklo - but it took a long time to figure out what went on, and that was only because it was a uranium mine that the level of detailed work was done. The most detailed radiation survey commonly done in exploration is gamma-ray spectroscopy, which uses a scintillator which can differentiate between decay of potassium-40, uranium-238, and thorium-232 (as indicators of clay minerals, adsorption of uranium onto sedimentary organic matter, and clastic sediment respectively). If you want a more detailed survey, you need to make a business case for the value of the information, and justify the cost of hiring a tool and running it.
The first words on the paper are "(in press Int. J. Astrobio)". This is the stage at which you do things like proof-reading. You also do things like putting the figures inline with the text, setting up captions, and formatting the reference list into the house style. This is a "pre-publication server".
More to the point, a stone tool that was useful (practically a definition of a tool) would be worth moving from where you found the original stone (this obsidian lava flow ; that flint-containing limestone) to another place where you used it (obviously, you could use it where you found the raw material too). When the tool is lost (dropped, tent burned down, whatever) and it gets embedded into the soil and becomes a fossil, it will be considerably different in size to most of the surrounding sediment. And that is something that shows up in the geological record for billions of years - I can track natural pebble bands like that in mountains a little along the road from here, and that gives me a baseline from which I can say "these unusually-shaped stones are unusual compared to the surrounding sediments".
It's a subtle point - but I look at rocks for a living, and that sort of thing is where you're looking to find evidence of where your sediment is coming from and going to ("provenance studies").
No land-based civilization could exist without wheels.
Flat out wrong.
The Inca (and preceding Andean civilisations) lived happily for many centuries with a sophisticated civilisation, and never putting wheels on anything larger than a child's toy.
Cities of tens of thousands - check!
Sophisticated agriculture and water management - check!
Isn't year-round icecaps the defining feature of an ice age?
No, that's the defining characteristic of an "icehouse" world, in contrast to a "greenhouse" world where there is no permanent polar ice. The planet seems to flip between the two, depending on the presence or not of polar continents, with a significant effect from ocean circulation modifying that driver. The Earth last went into ice house mode about the start of the Oligocene, as Antarctica moved into a polar position and developed a circum-polar ocean current which reduced heat flux from the tropics to the continent.
The distinction you're looking for is between "glacial" and "interglacial" periods. That can happen very fast (geologically) - a few thousands of years - and definition is poor. I was observing geomorphological signs of oscillations around the last glacial-interglacial transition when I was hill walking last weekend, and I wondered to myself - "Do I put more significance on the valley glaciers spreading out of the mountain blocks onto the plain, leaving terminal moraines. Or do I look at whether the glaciers reached down to the current sea level, another 30 miles away? Or do I look at the deep frost shattering on mountain peaks as evidence of them being nunataks rather than all the peaks being covered by an ice cap?" The end of the Younger Dryas in the Northern Hemisphere was about 11.9kyr BP, but do you count the Younger Dryas as a 1.2kyr duration glacial episode, or was it just a short cold spell (see also "stadial") in an interglacial that started at around 20kyrBP?
Some grains within some rocks within some regions of the Laurentian shield are more than 3.96 Gyr old. Others are barely over 1 Gyr old. It's a big and complex place. And none of it's rock grains are more than 5 Gyr old.
. If you were a construction worker who found a chunk of "modern" ceramic while excavating,
Quarry workers are actually pretty damned good at spotting "the unusual" in the ground. The literature is full of reports of the form "specimen first noted by workers who bought it to attention of [lead author] who performed a rescue excavation over [several days]"
Palaeontologists get a shift on to do a recovery excavation because you want this mine supervisor to report the next find as well, which could be more interesting than this one. Same for civils work.
an arrowhead of a totally unique style, would you think dinosapien, or would you think unknown human civilization?
That's a false dichotomy. Unless you're utterly incompetent, you'll know your regional styles (or know who to call) so you'll know it's a unique style while you're excavating it. So you'll be collecting all the additional environmental data, context information etc and really getting your recording data tied down tight. Because fucking up the field work is an unforgivable sin - you really might just as well throw the specimen away if you don't do your recording right.
How many oil reservoirs have you subjected to hand specimen, whole core, and/ or microscopic examination? Do you really have that much contempt for geologists?
Actually, the chemical and optical properties are quite distinct from almost all natural minerals. (Lechatelierite being an exception.) As you'll remember from the year or so you spent studying mineralogy, in order to speak with such confidence.
If you fracture a rock containing a glass inclusion, the glass is likely to be fractured as well - just another glassy inclusion unless the glass is clear enough and the break clean enough to let you see through to the surface.
Hmm, you speak with the conviction that make me think that you've looked at several hundreds of thousands more rock specimens than I have. Or maybe, you've not looked at even a single hundred thousand rock samples (you'd have crossed that measure some time in your second decade in the job)?
Actually, you get quite good at noticing unusual things after the first couple of years. Or you move into a different job like punching numbers into computers. You recognise them as unusual because the usual things you've written into the "Sample Description" forms so bloody often that the unusual stands out.
Yes, you do see unusually clear and polished grains occasionally. And you note them, because they're unusual. And you note that they appear and increase and decrease in certain units but not in others, which your seismic stratigraphy associates with one provenance region but not another. Significant and useful data. Evidence of a Pliocene civilisation? No.
Very interesting thought. It should certainly be possible to distinguish diamonds that were cut in the last 30 years or so:
That'll not survive longer than the script used. whether the ID numbers are recognisable as numbers, ID or otherwise, rather depends on the script still being in use, and the database still existing.
What would probably last longer are the tooling marks on the various cut and polished surfaces of the diamond. The techniques have changed a lot over the last few centuries with rotating laps (producing slightly-curved, concentric tool marks) replacing hand tools (irregular directions and non-flat surfaces) around the start of the 18th century. Around the end of the 19th century the abrasives changed from natural emery (magnetite-corundum mixture) to artificial SiC and BC with more consistent grain sizes and hardnesses - that will change the structure of the tooling marks.
As numerous people are pointing out text is optimally read in A4 form as determined by at least two thousand years of empirical experience.
Two thousand years? Not by a significant margin. Codex form (what we normally call "book") appeared around two thousand years ago, but didn't achieve dominance until well into the mediaeval period - 600 or 700 CE. Until then, the large majority of writing was produced on scrolls, because they were more compact than codices, and you could produce papyrus in nice long scrolls. As intellectual action in western Europe increased, without the ability to grow and produce papyrus, parchment became the writing surface of choice and this limited sheet dimensions to those of the side of a goat or calf. Codices then became the preferred format for storing information instead of scrolls.
All of which is about material availability, and none of it about experimentation in preferred document formats.
Having 10^8 subscribers sounds impressive. If you don't look at the rest of the numbers.
What is the number of people in the markets that Amazon "does" prime in? USA is 3*10^8 ; Europe 7.4*10^8 ; someone mentioned India has Prime service, so that's 13*10^8. I don't know if it's available in Russia - I'll ask Tebya Valentina next time we call her - or in China. But so far that's 1.0*10^8 subscribers out of a population of 23.4*10^8 potential customers. A bit less than 5%.
Are there really many people that order so infrequently?
Well, I got one Amazon delivery last year - which arrived in two instalments on different days, as expected. I'm about half way through that pile of books.
But once you get past that, and you see the convenience and vastly greater selection available, why would you ever give that up?
Who wants to wait the three of four days for delivery, when by going to the shop you can get what you need off the shelf there and then? Books are still the only thing I actually use Amazon for, and even then they're not my most regular book supplier because they've not got many that interest me.
You know that oxygen is essential to human life? No oxygen, blue lips, dead meat... all that jazz.
Did you know that oxygen is also a toxin with a pretty steep dose-lethality curve? Almost everyone is OK with 1.3 atmospheres of total oxygen pressure ; almost everyone dies at 1.8 atmospheres. Oxygen is a significant risk factor in a lot of cancers, by causing oxidative damage to DNA. It's both things at the same time.
Well, if you;d ever read "Origin" (which you clearly haven't) you'd know that large chunks of it's "one long argument" is based around the effectiveness of artificial selection in animal husbandry. Darwin himself was a "fancy" pigeon breeder.
I can't think off-hand of any chemicals used in Victorian Britain (and before) which produced the sort of heritable genetic changes you're looking for. People had certainly noticed that some diseases "run in families", but examples that lead to the association of certain chemicals with such heritable effects - I can't think of any before the early 20th century. Which was when environmental safety and product safety regulations started to bite. People were starting to see environmental toxic effects (e.g. testicular cancer in chimney sweeps ; mercury in Alice's "Mad Hatter" ; volatile arsenic compounds from bright green arseneous wallpaper dyes), but proving the connection to particular products was in it's infancy.
You seem a bit hazy on the structure of the theory. Evolution is the product of heritable within-species variation which is then selected to give differential breeding rates. Variation can be heritable or non-heritable, and only the heritable variations can be part of evolution. Selection can be artificial (by a human being - eg wanting a hairless breed of cat) or natural (by non-artificial forces - eg Siberian tigers having thicker coats than Indian tigers, because they spend more time in snow).
What I really want to see are more commercial aircraft that have rear-facing seats. I always take a rear-facing seat if the option exists. Far, far safer in anything more sphincter-twitching than a hard landing.
Google (and Youtube, Facebook etc) are very attentive to their customers. The problem is that some of their users are under the mistaken belief that they're customers, not product.
Could be a blip (in geological time) of a few decades or hundreds of years,
From the records of the most recent comparable atmospheric CO2 excursion, the time scale is going to be more like 100 thousand years. 120 thousand quite plausibly, it depends how far we turn the heat up.
That's still a "blip" geologically. Hell, it's barely a "bump" in terms of archaeology - Homo Sapiens as a species is between two and three times that old. Going back 100 thousand years would take us back through Neolithic and Mesolithic into the Paleolithic, but anatomically, they're still Sapiens.
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Approximately one new species of dinosaur (representing many individual fossils) is described every week. We are living in the "golden age of dinosaur discovery", today.
A fission war might leave a signal. Whether it'd still be detectable after dispersal over several vertical cm by bioturbation by recovering organisms a quarter million years after the bombs stopped falling is a different question, and far less clear to me.
Tritium would be effectively undetectable after 13000 years. Plutonium would be severely attenuated after a quarter million. Half lives do mean something. It might seem a long time to you, but it's peanuts geologically. Yes, we detected the shenanigans at Oklo - but it took a long time to figure out what went on, and that was only because it was a uranium mine that the level of detailed work was done. The most detailed radiation survey commonly done in exploration is gamma-ray spectroscopy, which uses a scintillator which can differentiate between decay of potassium-40, uranium-238, and thorium-232 (as indicators of clay minerals, adsorption of uranium onto sedimentary organic matter, and clastic sediment respectively). If you want a more detailed survey, you need to make a business case for the value of the information, and justify the cost of hiring a tool and running it.
The first words on the paper are "(in press Int. J. Astrobio)". This is the stage at which you do things like proof-reading. You also do things like putting the figures inline with the text, setting up captions, and formatting the reference list into the house style. This is a "pre-publication server".
More to the point, a stone tool that was useful (practically a definition of a tool) would be worth moving from where you found the original stone (this obsidian lava flow ; that flint-containing limestone) to another place where you used it (obviously, you could use it where you found the raw material too). When the tool is lost (dropped, tent burned down, whatever) and it gets embedded into the soil and becomes a fossil, it will be considerably different in size to most of the surrounding sediment. And that is something that shows up in the geological record for billions of years - I can track natural pebble bands like that in mountains a little along the road from here, and that gives me a baseline from which I can say "these unusually-shaped stones are unusual compared to the surrounding sediments".
It's a subtle point - but I look at rocks for a living, and that sort of thing is where you're looking to find evidence of where your sediment is coming from and going to ("provenance studies").
Flat out wrong.
The Inca (and preceding Andean civilisations) lived happily for many centuries with a sophisticated civilisation, and never putting wheels on anything larger than a child's toy.
Cities of tens of thousands - check!
Sophisticated agriculture and water management - check!
Central government and control - check!
What is this AC's definition of "civilization"?
No, that's the defining characteristic of an "icehouse" world, in contrast to a "greenhouse" world where there is no permanent polar ice. The planet seems to flip between the two, depending on the presence or not of polar continents, with a significant effect from ocean circulation modifying that driver. The Earth last went into ice house mode about the start of the Oligocene, as Antarctica moved into a polar position and developed a circum-polar ocean current which reduced heat flux from the tropics to the continent.
The distinction you're looking for is between "glacial" and "interglacial" periods. That can happen very fast (geologically) - a few thousands of years - and definition is poor. I was observing geomorphological signs of oscillations around the last glacial-interglacial transition when I was hill walking last weekend, and I wondered to myself - "Do I put more significance on the valley glaciers spreading out of the mountain blocks onto the plain, leaving terminal moraines. Or do I look at whether the glaciers reached down to the current sea level, another 30 miles away? Or do I look at the deep frost shattering on mountain peaks as evidence of them being nunataks rather than all the peaks being covered by an ice cap?" The end of the Younger Dryas in the Northern Hemisphere was about 11.9kyr BP, but do you count the Younger Dryas as a 1.2kyr duration glacial episode, or was it just a short cold spell (see also "stadial") in an interglacial that started at around 20kyrBP?
Some grains within some rocks within some regions of the Laurentian shield are more than 3.96 Gyr old. Others are barely over 1 Gyr old. It's a big and complex place. And none of it's rock grains are more than 5 Gyr old.
Quarry workers are actually pretty damned good at spotting "the unusual" in the ground. The literature is full of reports of the form "specimen first noted by workers who bought it to attention of [lead author] who performed a rescue excavation over [several days]"
Palaeontologists get a shift on to do a recovery excavation because you want this mine supervisor to report the next find as well, which could be more interesting than this one. Same for civils work.
That's a false dichotomy. Unless you're utterly incompetent, you'll know your regional styles (or know who to call) so you'll know it's a unique style while you're excavating it. So you'll be collecting all the additional environmental data, context information etc and really getting your recording data tied down tight. Because fucking up the field work is an unforgivable sin - you really might just as well throw the specimen away if you don't do your recording right.
If you think that sand looks like glass, then you are not very good at looking.
How many oil reservoirs have you subjected to hand specimen, whole core, and/ or microscopic examination? Do you really have that much contempt for geologists?
Actually, the chemical and optical properties are quite distinct from almost all natural minerals. (Lechatelierite being an exception.) As you'll remember from the year or so you spent studying mineralogy, in order to speak with such confidence.
Hmm, you speak with the conviction that make me think that you've looked at several hundreds of thousands more rock specimens than I have. Or maybe, you've not looked at even a single hundred thousand rock samples (you'd have crossed that measure some time in your second decade in the job)?
Actually, you get quite good at noticing unusual things after the first couple of years. Or you move into a different job like punching numbers into computers. You recognise them as unusual because the usual things you've written into the "Sample Description" forms so bloody often that the unusual stands out.
Yes, you do see unusually clear and polished grains occasionally. And you note them, because they're unusual. And you note that they appear and increase and decrease in certain units but not in others, which your seismic stratigraphy associates with one provenance region but not another. Significant and useful data. Evidence of a Pliocene civilisation? No.
That'll not survive longer than the script used. whether the ID numbers are recognisable as numbers, ID or otherwise, rather depends on the script still being in use, and the database still existing.
What would probably last longer are the tooling marks on the various cut and polished surfaces of the diamond. The techniques have changed a lot over the last few centuries with rotating laps (producing slightly-curved, concentric tool marks) replacing hand tools (irregular directions and non-flat surfaces) around the start of the 18th century. Around the end of the 19th century the abrasives changed from natural emery (magnetite-corundum mixture) to artificial SiC and BC with more consistent grain sizes and hardnesses - that will change the structure of the tooling marks.
Two thousand years? Not by a significant margin. Codex form (what we normally call "book") appeared around two thousand years ago, but didn't achieve dominance until well into the mediaeval period - 600 or 700 CE. Until then, the large majority of writing was produced on scrolls, because they were more compact than codices, and you could produce papyrus in nice long scrolls. As intellectual action in western Europe increased, without the ability to grow and produce papyrus, parchment became the writing surface of choice and this limited sheet dimensions to those of the side of a goat or calf. Codices then became the preferred format for storing information instead of scrolls.
All of which is about material availability, and none of it about experimentation in preferred document formats.
What is the number of people in the markets that Amazon "does" prime in? USA is 3*10^8 ; Europe 7.4*10^8 ; someone mentioned India has Prime service, so that's 13*10^8. I don't know if it's available in Russia - I'll ask Tebya Valentina next time we call her - or in China. But so far that's 1.0*10^8 subscribers out of a population of 23.4*10^8 potential customers. A bit less than 5%.
Sounds a bit less impressive like that?
Well, I got one Amazon delivery last year - which arrived in two instalments on different days, as expected. I'm about half way through that pile of books.
Who wants to wait the three of four days for delivery, when by going to the shop you can get what you need off the shelf there and then? Books are still the only thing I actually use Amazon for, and even then they're not my most regular book supplier because they've not got many that interest me.
As many as that?
You know that oxygen is essential to human life? No oxygen, blue lips, dead meat ... all that jazz.
Did you know that oxygen is also a toxin with a pretty steep dose-lethality curve? Almost everyone is OK with 1.3 atmospheres of total oxygen pressure ; almost everyone dies at 1.8 atmospheres. Oxygen is a significant risk factor in a lot of cancers, by causing oxidative damage to DNA. It's both things at the same time.
But that#s not a concern - only poor voters are likely to die in any significant numbers.
I can't think off-hand of any chemicals used in Victorian Britain (and before) which produced the sort of heritable genetic changes you're looking for. People had certainly noticed that some diseases "run in families", but examples that lead to the association of certain chemicals with such heritable effects - I can't think of any before the early 20th century. Which was when environmental safety and product safety regulations started to bite. People were starting to see environmental toxic effects (e.g. testicular cancer in chimney sweeps ; mercury in Alice's "Mad Hatter" ; volatile arsenic compounds from bright green arseneous wallpaper dyes), but proving the connection to particular products was in it's infancy.
You seem a bit hazy on the structure of the theory. Evolution is the product of heritable within-species variation which is then selected to give differential breeding rates. Variation can be heritable or non-heritable, and only the heritable variations can be part of evolution. Selection can be artificial (by a human being - eg wanting a hairless breed of cat) or natural (by non-artificial forces - eg Siberian tigers having thicker coats than Indian tigers, because they spend more time in snow).
What I really want to see are more commercial aircraft that have rear-facing seats. I always take a rear-facing seat if the option exists. Far, far safer in anything more sphincter-twitching than a hard landing.
Google (and Youtube, Facebook etc) are very attentive to their customers. The problem is that some of their users are under the mistaken belief that they're customers, not product.
From the records of the most recent comparable atmospheric CO2 excursion, the time scale is going to be more like 100 thousand years. 120 thousand quite plausibly, it depends how far we turn the heat up.
That's still a "blip" geologically. Hell, it's barely a "bump" in terms of archaeology - Homo Sapiens as a species is between two and three times that old. Going back 100 thousand years would take us back through Neolithic and Mesolithic into the Paleolithic, but anatomically, they're still Sapiens.
It'll come out in the same year as the Ringworld film.
The saying :
I've heard references to it pushing 200 years old, and it probably wasn't new then.