Life Without People

[tofu]

I've probably been toseeked, but I didn't see a thread about this show.

How many of you watched it last night on the History Channel? I thought it was pretty good. I especially liked the ending where they suggest that beings as intelligent as we are may never again evolve. I think most people take it for granted that they would, so I'm glad they put that possibility out there.

[Ronald Brak]

Personally I think that if Harry Potter waved his wand and all humans magically disappeared from the face of the earth, we'd see the rise of tool using intelligences comparable to us, given a not too long length of time. While evolution has no direction, it's a matter of what works, but larger brains, greater intelligence and tool use are strategies that have been useful for a great many animals and they are not likely to cease being useful without humans around.

[MrB398]

I saw it, I was pretty happy with it.

However I found it kinda stupid how they sugested in 150-200 years, the decendants of our house cats will all be living in jungle filled skyscrapers. Not that some cats wouldn't. But I wouldn't give that scenario the majority probability.

[tofu]

we'd see the rise of tool using intelligences comparable to us, given a not too long length of time.

So, it takes four billion years to do it the first time, complete with many false starts (why weren't the dinosaurs smarter?) and almost didn't happen (if life hadn't become difficult in that rift valley, our ancestors wouldn't have been selected for intelligence) and even when it intelligence does evolve, it sometimes cannot be leveraged (whales might be theoretical physicists, but so what? Cats might become smarter, but with sharp vision and opposable thumbs they can't do much with it) . . .but given a second chance, you think it's a sure thing? hmm, I don't know.

[Noclevername]

Personally I think that if Harry Potter waved his wand and all humans magically disappeared from the face of the earth, we'd see the rise of tool using intelligences comparable to us, given a not too long length of time. While evolution has no direction, it's a matter of what works, but larger brains, greater intelligence and tool use are strategies that have been useful for a great many animals and they are not likely to cease being useful without humans around.

It's just one among millions of proven survival strategies. And with random mutation, new ones can pop up all the time. So no guarantee that that particular one will happen in just the right way to again create something comparable to us (not just in terms of tool use and intelligence, but it would also need a high capacity for abstract thought, curiosity, learning, and creativity to be like us).

[Ronald Brak]

So, it takes four billion years to do it the first time, complete with many false starts (why weren't the dinosaurs smarter?) and almost didn't happen (if life hadn't become difficult in that rift valley, our ancestors wouldn't have been selected for intelligence) and even when it intelligence does evolve, it sometimes cannot be leveraged (whales might be theoretical physicists, but so what? Cats might become smarter, but with sharp vision and opposable thumbs they can't do much with it) . . .but given a second chance, you think it's a sure thing? hmm, I don't know.


Say what? Harry Potter is making humans disappear, not bacteria aned everything else as well. Some dinosaurs were smarter than others, or at least had better brain body ratios than others. If you plot the largest brain body ratios we are aware of through time you'll see it trends upwards. And I said nothing about a sure thing. I began my post with the words, "Personally I think..." which is a long way from stating that something is a sure thing. Being aware of nuance is important for reasonable discussion.

[Ronald Brak]

It's just one among millions of proven survival strategies. And with random mutation, new ones can pop up all the time. So no guarantee that that particular one will happen in just the right way to again create something comparable to us (not just in terms of tool use and intelligence, but it would also need a high capacity for abstract thought, curiosity, learning, and creativity to be like us).

How likely another intelligent advanced tecnological species would be just like us is debatable. But the evolution of another advanced technological species does not seem unlikely to me, given the magical disapearance of humans. We know that technology is useful and we know that there are many tool using animals out there. It seems unlikely to me that no species would progress in the direction higher levels of technology. Random mutations happen all the time and could result in the evolution of improved tool use among ravens, babboons, otters, orangutans or many other species.

[soylentgreen]

LIFE AFTER PEOPLE was pretty enjoyable, a refreshing change from the ghost chasing, rod filming, motorcycle building garbage that usually gets played on the "learning" type channels.

The show makes a decent companion to Alan Weisman's book "The World Without Us". Of course, the show can only scratch the surface of the idea. I did enjoy

As a fellow who spent my fair share roaming the abandoned locales of my "Weird" state, I could appreciate their use of the urban ruins we already have. While it probably wasn't, it did appear to be the old Paulinskill Viaduct behind Dr Brin...another favorite destination.

I was particularly moved by the segment at Pripyat. The poignant tour of the abandoned amusement park and school was quite haunting. It brought back memories of visiting the forgotten(and now completely gone!) Essex Mountain Sanatorium (http://www.youtube.com/watch?v=uC20wcLKGxg)*

The comment about our radio and television signals becoming indistinct mush relatively quickly was a bit disheartening.
However I found it kinda stupid how they sugested in 150-200 years, the decendants of our house cats will all be living in jungle filled skyscrapers. Not that some cats wouldn't. But I wouldn't give that scenario the majority probability.
I could buy the speculation with a little more ease than the one about an evolutionary leap to "flying cats". Now that seemed a little much.


*...for the hyperlink-frightened, a youtube vid in honor of the Asylum on the Hill(No, not the Capitol Building)

[idav]

I've probably been toseeked, but I didn't see a thread about this show.

How many of you watched it last night on the History Channel? I thought it was pretty good. I especially liked the ending where they suggest that beings as intelligent as we are may never again evolve. I think most people take it for granted that they would, so I'm glad they put that possibility out there.
As long as there is reproduction there will be evolution. It's as inevitable as death. I really don't see that as a possibility at all.

[toejam]

As long as there is reproduction there will be evolution. It's as inevitable as death. I really don't see that as a possibility at all.

Sounds as though I missed a good program. As for human beings:-

It has been said that Man is a rational animal. All my life I have been searching for evidence which could support this.
--Bertrand Russell.

[idav]

Russ is THE man!

[tofu]

As long as there is reproduction there will be evolution. It's as inevitable as death.
Of course!
I really don't see that (the possibility that no more technological civilizations would evolve after we die out) as a possibility at all.
Wait. I don't see how statement 1 has anything at all to do with statement 2.

Yes, evoluton is inevitable. But that doesn't necessarily imply that a technological civilization is going to evolve. It's a chance, but not a certainty.

[RalofTyr]

Humans aren't going to disapear one day, unless you read the Bible too much. How will we become extinct? Like most species, we will be replaced by a more efficient species, perhaps h0mo sapien sapien will be replaced by h0mo sapien machina.

And I missed that show, though, I really wanted to see it. Damn GF and her grocery shopping!!!

[Romanus]

I thought it was very good, certainly one of the best sci-documentaries I've seen (and I've seen a lot). It's showing again tonight, so set your VCRs and whatnot. :)

<<I could buy the speculation with a little more ease than the one about an evolutionary leap to "flying cats". Now that seemed a little much.>>

I totally agree; I think that would be within the realm of possibility only if the skyscrapers lasted *much* longer than currently expected sans people. That is, after all, a fairly specialized adaptation to pop up in only a couple of centuries IMO.

[mike alexander]

Given the total number of species that have evolved on earth since multicellular life emerged, and the documented existence of one (1) intelligent one, we might call 'intelligent life' a truly singular event, unlikely to be repeated.

The posession of a very large brain/body ratio imposes some real drawbacks on an organism. And it's more than just a big brain, adequately organized, that makes us smart.

[aurora]

Humans aren't going to disapear one day, unless you read the Bible too much. How will we become extinct?


There's lots of ways it could happen. And looking at geological history, I would argue that it will happen, and when it does there is not guarantee that we will be the ones who will evolve into a superior species.

Species go extinct. Mammalian species go extinct.

[Maha Vailo]

Could the reason that we believe there was only one known intelligent, technological civilization on this planet be the sheer fact that any evidence of technological civilizations would crumble into dust in the span of many millenia? The dinosaurs (for example) may well have had sentient species among them - it's just that any evidence of them having been that way would fossilize poorly.

It's just a hypothesis, I could be wrong.

- Maha Vailo

[EndeavorRX7]

We will either get hit by an apocalyptic asteroid or evolve into something else and then somewhere down the road become extinct somehow. End of story.

[agingjb]

Hmm. I do wonder if the human species is like the cockroach, likely to survive virtually any catastrophe, or like the flightless rails on isolated islands, doomed by the arrival of cats or rats.

In any case, although I'd guess that various forms of intelligence would evolve in our absence, there is little reason to suppose that this intelligence would produce anything with which we would have much in common - even if it were of comparable complexity.

[mike alexander]

There are indirect indicators that a highly technological nonhuman species has never evolved. Easily tapped oil and mineral reserves suggest they were not mined previous to the appearance of humans, for example.

[EndeavorRX7]

Maybe it was sooo long ago that whatever minerals or oils they tapped got replenished or were never there to begin with. I am one to believe that we are the most advanced to ever exist on this planet, but I or anyone else cannot prove it. I think the only way to ever know what happened here billions of years ago is time travel. But how do we do that?

[RalofTyr]

OK. I just saw it.

Every time a high rise collapsed, I thought, "Those poor kitties".

200 million years in the future, the Squibbians, will find lots of evidence of our exsitence. There'd be appear in the fossil record as if all the iron, carbon and other elements we used where taken from older layers and redistributed. Some of our artifacts would remain as well as a few of our fossils. There are billion and billions of us. When they go into space, their probes will examine the moon, eventually more closely than our probes do, and they will find the Apollo sites and have proof of us.

Likewise, there could have been an intelligent species on Earth 250MYA. That don't have coal, but they have a few sources of gas.

There is evidence, strange artifacts that have been found, such as cicular metallic balls dating about 2 billion years ago, in Africa. They could be natural. They could not be. We may have been visited and colonized many times before.

The end.

[Romanus]

I think there will be plenty of evidence of us tens or even hundreds of millions of years down the road. It probably won't, however, be something that anyone aside from a geologist would easily notice.

[EndeavorRX7]

There is evidence, strange artifacts that have been found, such as cicular metallic balls dating about 2 billion years ago, in Africa. They could be natural. They could not be. We may have been visited and colonized many times before.

Did you find this on the internet? I'd like to see where you got this info. In the meantime I will try to google it up.

[Bolasanibk]

Not the most reliable of the sources, But still a good starting point:

Wikipedia:Klerksdorp_Spheres (http://en.wikipedia.org/wiki/Klerksdorp_Spheres)

[Ronald Brak]

Given the total number of species that have evolved on earth since multicellular life emerged, and the documented existence of one (1) intelligent one, we might call 'intelligent life' a truly singular event, unlikely to be repeated.

This seems a very odd way to look at it. The first vertebrate on land might concluded that since it was the only of it's kind to conquer land vertebrate land life was a truely singular event, unlikely to be repeated. But the chance of something with an intelligence equivilent to a human's evolving has not been constant since multicellular life first appeared. It needs decent raw material to work with and there is more raw material in the form of both intelligent and tool using animals now than at any other point in the history of life. (Despite humans rendering some extinct.) There is not only one intelligent species on earth and many evolved their intelligence independantly of each other. Consider apes, whales, capuchins, elephants, artic wolves and corvids.

The posession of a very large brain/body ratio imposes some real drawbacks on an organism. And it's more than just a big brain, adequately organized, that makes us smart.

So what else besides a big brain, adequately organized that makes us smart? Are you refering to extelligence? That is intelligence embodied in artifacts we make? There is evidence for that in other animals as well, although obviously humans are the champs at it.

[Neverfly]

This seems a very odd way to look at it. The first vertebrate on land might concluded that since it was the only of it's kind to conquer land vertebrate land life was a truely singular event, unlikely to be repeated. But the chance of something with an intelligence equivilent to a human's evolving has not been constant since multicellular life first appeared. It needs decent raw material to work with and there is more raw material in the form of both intelligent and tool using animals now than at any other point in the history of life. (Despite humans rendering some extinct.) There is not only one intelligent species on earth and many evolved their intelligence independantly of each other. Consider apes, whales, capuchins, elephants, artic wolves and corvids.

The posession of a very large brain/body ratio imposes some real drawbacks on an organism. And it's more than just a big brain, adequately organized, that makes us smart.
Brain size is mostly a specific trait. It isn't universal.
Avian brains work differently than mammal brains. A bird can be much more intelligent than a much larger brained mammal. Intellect is not limited to brain size- rather how the brain functions.

[tofu]

So what else besides a big brain, adequately organized that makes us smart? Are you refering to extelligence? That is intelligence embodied in artifacts we make?

I don't know about anyone else, but I'm talking about all the unrelated things that have to happen just so for an advanced *civilization* to arise. So I'll repeat my reasons:
1. whales might be theoretical physicists, but so what? They have little power to manipulate their environment. They might live to the heat death of the universe, but they will never have technology and will never leave this planet unless someone takes them. Even with their intelligence, they're in an evolutionary culdesac.

2. Cats might become smarter, but their eyes hold them back. One of the things necessary for an advanced civilization is the ability to pass arbitrarily complex information from one generation to the next - basically, reading and writing. Cats have very poor detail vision. A book with type large enough for a cat to read would be enormous. Furthermore, even though they could do a better job of manipulating their environment than whales, they don't have opposable thumbs.

My point is, I think you're focusing too much on brain power. That may be the most important attribute that must evolve, but it's not the only one. These other attributes (I've named two but there are many more) must also be present. There's just no way around that.

And these attributes are essentially unrelated. Evolution works precisely because it is not random. But the appearance of all these unrelated attributes in the same species was actually completely random. That makes it far less likely to be repeated.

I agree with you, another intelligent species will evolve. They might be dogs. They might be whales. But they wont develop an advanced civilization.

The best candidate species is probably the chimpanzee, but they're 99% the same as us already. For another species, that doesn't start out like us, they would have to be extremely lucky to have all the required attributes - so lucky in fact that I doubt it will happen.

[farmerjumperdon]

I saw parts of it. Relatively entertaining.

Given enough time and the proper ingredients, I believe life is inevitable. Obviously there are plenty of places with the ingredients, and it appears the Universe will be around for a good bit of time. Life is just a matter of the right goodies coming together and chemical reactions taking their course.

I also believe that evolution of intelligence, really just a biological subset of chemical processes, is equally inevitable; again, given enough time and readily available ingredients.

What's the saying? Given enough time, anything that is possible is probable? Or something like that. I think most doubts about that are founded in the need to think we are special. On the scale of our planet we are special only because we got to this point first. On the scale of the Universe, I believe we are no big deal.

[tofu]

I also believe that evolution of intelligence, really just a biological subset of chemical processes, is equally inevitable;

I agree, but I think the debate here is if there will be another technological civilization. Intelligence isn't enough to make that happen.

While driving in to work today, I remembered the book, Guns, Germs, and Steel. I think it makes another interesting point in support of my position.

Consider the aboriginal people of Australia. They arrived on the continent 70,000 years ago as hunter/gatherers. And 70,000 years later, they were still hunter/gatherers. Meanwhile, in the middle east (in the place called the fertile crescent) they discovered agriculture just 9000 years ago, and their civilization became so powerful that it dominated the globe. But the people, the humans, in each of those situations are basically the same. What makes the difference between an unending, unprogressing, hunter/gatherer state, and a high technological civilization, is the environment. The people of the fertile crescent had a wealth of domesticatable plants and animals. The people of Australia did not.

So, after 70,000 years they had no agriculture, no written language, no ability to pass on arbitrarily complex ideas (I'm sorry, but songs and dances don't accomplish that), no math, nothing. I see no evidence that given another 100,000 years, or another million years of isolation, that anything would change - unless their environment changes. They are just as intelligent as anyone else, but because of their environment, they're stuck.

I'll repeat my thesis: I agree that intelligence is an inevitable product of evolution. The debate here is if another high technological civilization would arise on Earth if humans were gone. I think it's possible, but unlikely. It's unlikely because it depends not on evolution, which is inevitable, but on a lucky combination of many factors. This post discusses one of those factors: availability of plant and animal species that can be domesticated. We humans simply got lucky. We just happened to evolve in a time and place where such species exist. If the entire world were Australia, humans would not have a technological civilization - and no amount of intelligence could change that.

And there are other, similar lucky happenstances that I've discussed in previous posts.

[Ronald Brak]

So, Tofu, you are saying that civilization would be unlikely to arise if humans were gone. Civilization is quite different from intelligence or technology use. As you point out, Australians were quite intelligent, but did not develop civilization. However, Australians did use a lot of technology, but it was a stone age level of technology. I agree that it would be vastly more difficult for Australians to develop civilization than people in Eurasia, but I don't see it as impossible. Hunter gatherer technology progressed enormously over the past 50,000 years, going from fairly primitive stone tools to clothes, fish hooks, baskets, canoes, spear throwers, fish traps - a fast array of advances, all present in Australia. I doubt that the technological improvement would have just stopped, although the environment probably would have greatly slowed development and would have made some things very difficult.

[ToSeek]

The bit I caught made my eyes hurt, with all the fancy whooshy camerawork. Is the whole thing like that?

[tofu]

Civilization is quite different from intelligence or technology use.
This is a good point, and I don't want to sound like I'm speaking in absolutes. I don't think there's a fine line between civilization and not civilization. Honestly, I'm not even sure I can define it.

As you pointed out in one of your previous posts, chimpanzees already have technology that they use to obtain termites. And I've seen very impressive videos of crows bending a wire to make a tool.

So what if we set some arbitrary bar to define the level of civilization and technology that we want to talk about? How about, radio telescopes? What I'm suggesting is that it's unlikely another civilization would arise and build radio telescopes. Maybe there's a better litmus test, but this is what popped into my head.

Chimpanzees are a shoe-in I suppose. They already have all of the physical attributes I think are necessary. But if we disregard them, I think it's unlikely that another species would be lucky enough to evolve all those needed physical attributes. Crows for example, in spite of their intelligence and technology, seem to me unlikely to have the potential to go much further. Maybe elephants could do it.

I doubt that the technological improvement would have just stopped, although the environment probably would have greatly slowed development and would have made some things very difficult.

No, I agree with you. Development would continue, but I think it's like an asymptotic approach, that gets closer and closer to the X axis, but never actually touches it.

One of the things that you need for a technological civilization is a sedentary lifestyle and a population of specialists. You need tradesmen, miners, iron-workers, etc. When you develop agriculture, you suddenly find that you have food surpluses. A few farmers can feed the entire population. Now the remainder of the population is free to go to school, to develop math and science, and to work toward technology.

But agriculture is not something that can be had by sheer force of will. You have to get lucky enough to have the right plant species around. The people of Australia didn't get lucky and there's nothing at all that they could do about it. You also need the right animal species. The people of America had agriculture, as you know, but they lacked oxen to pull plows. So even their corn wasn't enough.

In an asymptotic approach (I hope I'm using that term correctly) the curve is constantly moving closer to the X axis, but it never touches. For a hunter/gatherer culture, that might mean constantly improving spears, nets, hunting techniques, but it's never enough - in fact, it might be a bad thing. When they hunt a species to extinction they have nothing to fall back on.

So, some species evolves intelligence. That's nice, but it's not enough. They must also be lucky enough to have other physical attributes. If they are that lucky, they must be even more lucky to have an environment that provides a surplus of storable, transportable food.

[Noclevername]

Why are chimps still chimps, while we, their closest genetic cousins who share a common ancestry, changed so radically? Evolution is adaptation. They didn't change much because they didn't need to. They are best suited to a lush jungle environment. Unless that changes, they'll stay best suited to their environment. It's only because protohominids found themselves in a harsher land than they were adapted to that they were forced to develop alternate means of survival. According to the fossil record, ome of those means included first upright posture, then improved manual dexterity and tool use, and then increased brain size and development. Since the areas where most chimps currently live have a different set of conditions than those that drove our ancestors' evolution in this direction, their adaptations will be different.

[aurora]

Why are chimps still chimps, while we, their closest genetic cousins who share a common ancestry, changed so radically?


Chimps have changed, too. Our common ancestor was neither chimp nor human.

[agingjb]

I'm still somewhat sceptical about the appearance of a genuinely technological civilisation, although given long enough I suppose it's possible.

One development that is probably science fiction is the emergence of co-operating species, elephants and parrots, whales and cephalopods, who knows, complementing each other's capacities in some way. Pure fantasy, I suppose.

[Ronald Brak]

One development that is probably science fiction is the emergence of co-operating species, elephants and parrots, whales and cephalopods, who knows, complementing each other's capacities in some way. Pure fantasy, I suppose.

Um, happens all the time on earth.

[agingjb]

Well yes, symbiosis is everywhere, but co-operative and conscious development of the transmission of information using extra-biological media?

[Noclevername]

Chimps have changed, too. Our common ancestor was neither chimp nor human.

Yes, they have. But not much. That's why I said, "They didn't change much".

[Ronald Brak]

Well yes, symbiosis is everywhere, but co-operative and conscious development of the transmission of information using extra-biological media?

So you mean if an elephant picked up a piece of chalk and drew a circle around where the ticks were so a parrot would come and eat them? The chalk being the extra-biological part.

[agingjb]

Might take a little longer than that.

I haven't a clue really, but if alleles that eventually generated that sort of symbiosis were a survival advantage for the individuals and line to which they were transmitted, then I suppose it could emerge. An "Extended Phenotype" as Dawkins calls it.

[BigDon]

Back to the op, I found the 200 year wait until the "age of collapses" a bit long. We went from taking potshots at His Majesty's army to landing on the Moon in that amount of time. On the other hand I don't see a skyscrapper as being fragile either. That one has my mind flipflopping back and fourth.

[Ronald Brak]

I'm guessing that sky scrapers wouldn't hang around too long. I think fire would destroy or severely damage a lot of them. A burnt out building with the windows gone will have little protection from the elements. I wonder what effect the wind packing a weakened skyscraper with thousands of tons of snow would have?

[BigDon]

They went into that Ron. Least ways on how the loss of a few windows causes a downward spiral.

[Ara Pacis]

I think it's quite possible that a civilization by another animal could evolve on earth. Evolution doesn't consciously move toward anything, but it has already evolved the biosphere to a point that it can support humans. Thus, it would probably be able to support another such animal without having to re-evolve the planet from scratch. We already have fruiting angiosperms and grasses. It's not likely that the planet will devolve to the environment the dinosaurs had. Sure, something could happen to the planet to destroy the current biosphere, but we can't predict that.

But I was thinking about the idea that Mt. Rushmore would be our last legacy... wouldn't the next glaciation be to its detriment?

[Romanus]

^
We discussed that on another board; in fact, the longevity of Rushmore was exaggerated, as even today the faces have to be regularly maintained to keep noses and chins from falling off. Still, they might be vaguely recognizable for a pretty long time.

Re glaciers: IIRC, the Black Hills have never been glaciated, at least not during the last stage.

[Neverfly]

^
We discussed that on another board; in fact, the longevity of Rushmore was exaggerated, as even today the faces have to be regularly maintained to keep noses and chins from falling off. Still, they might be vaguely recognizable for a pretty long time.

Re glaciers: IIRC, the Black Hills have never been glaciated, at least not during the last stage.

The Sphinx at Giza has lasted a little while. Albeit his sense of smell isn't what it once was, but these things happen when you get older...

[Gillianren]

The Sphinx at Giza has lasted a little while. Albeit his sense of smell isn't what it once was, but these things happen when you get older...

Especially when French soldiers shoot your nose off.

Yeah, Mt. Rushmore actually wasn't all that sensible a place to carve that monument, given that the mountain itself is a bit unstable.

[Ronald Brak]

Especially when French soldiers shoot your nose off.

In all fairness to Napoleon's soldiers, we do have sketches of the sphinx dating from before their arrivial that show it without a nose. But when I was in school my teacher did tell me the French shot it off.

[aurora]

^
Re glaciers: IIRC, the Black Hills have never been glaciated, at least not during the last stage.

That is correct, in the Dakota's the line of glacial advance was approximately where the Missouri River is today, so the western half of South Dakota (where the Black Hills are) was not under the continental glaciers.

[aurora]

Yeah, Mt. Rushmore actually wasn't all that sensible a place to carve that monument, given that the mountain itself is a bit unstable.

How do you figure that? It is precambrain granite, which comprises the southern center of the Black Hills, and it is pretty resistant to erosion.

There are some cracks in the granite, which eventually, with the freeze thaw cycle, split. But that takes a long time.

I think Rushmore will be recognizable as something man made long after stuff like the pyramids is eroded away.

[Ronald Brak]

I think Rushmore will be recognizable as something man made long after stuff like the pyramids is eroded away.

That seems very unlikely to me. You can erode a meter off the great pyramid and you still have a pyramid. Erode a meter off Mount Rushmore and it will look like four trolls. Erode two meters and you have an odd looking cliff while the pyramid is still a pyramid.

[Gillianren]

How do you figure that? It is precambrain granite, which comprises the southern center of the Black Hills, and it is pretty resistant to erosion.

There are some cracks in the granite, which eventually, with the freeze thaw cycle, split. But that takes a long time.

Yes, but it's been happening for a long time. They've been having problems with the cracks in the rocks since they started carving there. It turns out I don't "figure" that; I read it when I was reading about the carving in one of my beloved history books. Lincoln's nose is pretty close to falling off right now, and it's not a new problem. According to what I've read, while it was pretty important to the South Dakotans to have some reason for anyone to visit South Dakota, Mount Rushmore was actually a pretty bad place to make the monument, much less maintain it.

[aurora]

That seems very unlikely to me. You can erode a meter off the great pyramid and you still have a pyramid. Erode a meter off Mount Rushmore and it will look like four trolls. Erode two meters and you have an odd looking cliff while the pyramid is still a pyramid.

Except that Sandstone erodes at a different rate than granite.

[aurora]

Lincoln's nose is pretty close to falling off right now, and it's not a new problem. According to what I've read, while it was pretty important to the South Dakotans to have some reason for anyone to visit South Dakota, Mount Rushmore was actually a pretty bad place to make the monument, much less maintain it.

Do you have a cite for the bit about Lincoln's nose? I'm wondering if it isn't quite as imminent as you recall.

[Gillianren]

Do you have a cite for the bit about Lincoln's nose? I'm wondering if it isn't quite as imminent as you recall.

Oh, dear. I'm afraid I don't remember which book I read it in! I remember reading it in several, actually; I'm pretty sure they've already had to take corrective measures. Naturally, the Wikipedia page (not the best resource, granted, but the easiest to access) has nothing about it, and I certainly don't expect you to take my unsupported word for it. I'll go digging through my books here and see what I can find, but it'll be in the morning.

[Ronald Brak]

Except that Sandstone erodes at a different rate than granite.

I'd imagine the limestone great pyramid erodes much slower than the granite mount rushmore. No freeze thaw cycle and a dry environment not conductive to plant growth. The fact that it has lasted four and a half thousand years so far, and has survived earthquakes and stone theft, while Mount Rushmore needs regular maintance to stay pretty, makes me want to put my money on the great pyramid.

[Ronald Brak]

Do you have a cite for the bit about Lincoln's nose? I'm wondering if it isn't quite as imminent as you recall.

I'm Australian and even I know Lincoln's nose is held on by pins. Mind you, I thought it might have actually been the real Lincoln. I mean, after all, George Washington had wooden teeth, didn't he?

[Neverfly]

I'm Australian and even I know Lincoln's nose is held on by pins. Mind you, I thought it might have actually been the real Lincoln. I mean, after all, George Washington had wooden teeth, didn't he?

No, they were made of Ivory.
Washington had several sets of teeth actually. Some had some wood parts. Springs, metal, wood, Ivory....

Must have been pretty uncomfortable to wear...

[mike alexander]

Australians were quite intelligent, but did not develop civilization

Sorry, this just caught my eye.

Before going on much farther, a decent definition of civilization might be in order. I suggest that the techno- aspects of the past few hundred years have little to do with it, as pleasant as they have made things for those of us who can avail ourselves of them.

[Gillianren]

No, they were made of Ivory.
Washington had several sets of teeth actually. Some had some wood parts. Springs, metal, wood, Ivory....

Must have been pretty uncomfortable to wear...

It's one of the reasons you never see pictures of him smiling, I promise you. (And he seems to have been a pretty serious guy in a lot of respects; he didn't really want to be President at all.)

[aurora]

Oh, dear. I'm afraid I don't remember which book I read it in! I remember reading it in several, actually; I'm pretty sure they've already had to take corrective measures. Naturally, the Wikipedia page (not the best resource, granted, but the easiest to access) has nothing about it, and I certainly don't expect you to take my unsupported word for it. I'll go digging through my books here and see what I can find, but it'll be in the morning.

Thanks. I did a quick Google search and came up empty. Which is why I asked.

I also read the book that is the focus of this thread, but I don't recall now what the author said specifically about the lifetime of Rushmore, and I had to return the book to the library (there is currently a waiting list of over 60 people for it), so I can't look it up without visiting a bookstore.

[aurora]

I'd imagine the limestone great pyramid erodes much slower than the granite mount rushmore. No freeze thaw cycle and a dry environment not conductive to plant growth. The fact that it has lasted four and a half thousand years so far, and has survived earthquakes and stone theft, while Mount Rushmore needs regular maintance to stay pretty, makes me want to put my money on the great pyramid.

No, the limestone abrades much more readily. The unfractured granite surfaces will last an incredibly long time.

And, but the Sahara will not always be a desert.

Once the human caused atmosphere changes disappear (I think the book was suggesting 100,000 years, but I could remember that completely wrong and can't check it as I said in the previous message, maybe it was 10,000), we'll have ice ages again and the Sahara will be quite wet once again (as it was in the period immediately before the rise of the Egytian civilization).

Also, there is a lot more wind erosion at the pyramids. When you are talking thousands and tens of thousands of years, wind erosion becomes significant, unless the pyramids end up being buried (as many smaller pyramids have been buried). I suppose in deep time, the Nile will change it's course, too, that could be significant.

Also, my point is that "staying pretty" is different from being recognizable as human caused.

The Great Pyramid is certainly not pretty anymore, yet it is obviously human built.

[Ronald Brak]

Before going on much farther, a decent definition of civilization might be in order. I suggest that the techno- aspects of the past few hundred years have little to do with it, as pleasant as they have made things for those of us who can avail ourselves of them.

Civilization is generally considered to have existed where there is evidence of a central authority and large scale building projects, such as roads, temples, casinos and so on.

[Ronald Brak]

It's one of the reasons you never see pictures of him smiling, I promise you. (And he seems to have been a pretty serious guy in a lot of respects; he didn't really want to be President at all.)

Yes, it seems he was much more interested in growing hemp.

[Noclevername]

For those of you wondering, what I had originally written in this post was meant to go in another thread. Therefore please ignore what is written here, it has no meaning.

Thank you in advance for your cooperation.

[Gillianren]

Yes, it seems he was much more interested in growing hemp.

It is a useful plant, after all. (To the best of my understanding, there's something that must be done to the plants in order to make them, um, have special properties, and I'm not sure there's any evidence that he did. However, my knowledge of the plant in any form except as cloth or rope is pretty limited.) It's not as useful as some people would have you believe, but still pretty useful.

[HenrikOlsen]

Found a bit of info on Mt. Rushmore here (http://www.outdoorplaces.com/Destination/USNP/sdmtrsh/index.htm)

Mount Rushmore has gone through a series of repairs over the last fifty years. There are some visible cracks in the face of the memorial and recently these cracks were filled with silicone based material to keep water out. This technique of preservation has been used for over 30 years in the White Mountains of New Hampshire to save the Old Man On The Mountain from similar damage. The endless cycle of freeze and thaw that happens in the Black Hills would eventually destroy the memorial, but the recently completed sealing and repairs should keep it around for thousands of years.

Also mention here (http://edition.cnn.com/TRAVEL/NEWS/9809/25/rushmore.repairs/index.html) with a piccy where you can see a fissure across Lincolns nose. This article mentions that the monument is inspected for new cracks every year and they are filled with silicone.
With regular maintenance, the busts -- carved between 1927 and 1941 -- are expected to have a long life; the monument erodes only at a rate of about one inch (2.54 centimeters) every 10,000 years.
Note that this is with annual filling of the cracks.

Then you have something like this (http://www.karcher.com/int/Sponsoring/Projects/Mount_Rushmore/Mount_Rushmore_August_1.htm), a German company who offered to clean the monument for free, which they got to do, apparently with very little consultation with conservation people about the longterm effects on the monument.

[Gillianren]

Thanks for that, Henrik; I'm now thinking it's a library book and not one in my personal collection in which I read that information. This, as I'm sure you can imagine, widens the possible number of books I read it in considerably, and while I've put a few books about Mt. Rushmore on hold at the library, they won't be in for at minimum a few days.

[Jim]

Quote:
Australians were quite intelligent, but did not develop civilization...

Sorry, this just caught my eye.

Before going on much farther, a decent definition of civilization might be in order. ...

As evidence, I give you Australian Rules Football.

(I leave it to the reader to decide if that is an argument for or against Australian civilization.)