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Civilizational Collapse, Part 4

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Re: Civilizational Collapse, Part 4

#121

Post by JoeAltmaier »

dredmorbius wrote: post #117
JoeAltmaier wrote: post #96

Earlier quoted context omitted.

The old joke: "How can you tell if someone is a Vegetarian? They'll tell you."

How can you tell if someone is a meat eater? They'll complain that you're a vegitarian.

Hm. Its pretty different. I don't come to a table and say "Hey! I'm a meat eater! Better supply me with meat in this meal, or I'm going to walk away!"

Clearly, on one side, we have omnivores. On the other, extra rules about food type and preparation. Its almost always more complicated to feed one, than the other.

Re: Civilizational Collapse, Part 4

#122

Post by beat »

dredmorbius wrote: post #97
chrisco255 wrote: post #41

This quote: "Ecologically, these Archaic hunters and gatherers had moved one entire link down the food chain, thereby eliminating the approximately 90-percent loss in food value that occurs when one feeds on an animal that is a plant-eater." This is just completely false. All meat consumed is bioavailable protein and nutrients. Even more so when it's cooked. Plants have reduced bioavailability due to high oxalate, ph…

The reference is to trophic levels and caloric loss. Plants, in net, capture about 1-3% of available solar energy and convert that to equivalent biomass. Food conversion -- the parts you can eat -- are a small fraction of that. Herbivores and predators each convert about 10% of the food energy they eat into body mass, for a 90% reduction (approximately) at each trophic level. Grazers lose 90% of the primary plant foo…

Technology changes that game.

Grains are the core of the human diet, and have been since the dawn of civilization. But they are only edible because of civilization - the grinding, fermentation, and cooking breaking them down into something our bodies can use.

In the US and other wealthy countries, we might feed grain to livestock, but it's also often parts of grain that we can't really eat (hulls, etc). And in poorer countries, livestock are often open-grazed on grasses that are inedible for us. And non-grazers like hogs often eat garbage, food waste that we don't consume.

When farming, the questions are even more complex. The livestock generates manure that fertilizes the fields, so much of that "lost" energy is recovered.

Re: Civilizational Collapse, Part 4

#123

Post by ekianjo »

pygy_ wrote: post #28
ekianjo wrote: post #24

Earlier quoted context omitted.

> there currently is one single civilization earth. All the cultural diffences between countries are far less than it would take to define different civilizations What is your definition of a civilization then? As far as i know there is no "global" culture, you can live in many different places and have a totally different everyday life experience.

Science and technology (and maybe trade?) are our global culture.

I just said there is no such thing as a global culture. It's not because you have Starbucks in every big city that the experience of living in different places is the same.

Re: Civilizational Collapse, Part 4

#124

Post by comicjk »

monocasa wrote: post #42
JoeAltmaier wrote: post #32

Earlier quoted context omitted.

Oh you could shortcut tremendously. Once photography was invented (1830s) we could have had integrated circuits. If we had known they were possible. Which we do now. There's ideas that can survive long after devices turn to dust. The germ theory of disease. The Staff system. Ops planning. Cross-fertilization and hybridization. Optics. With these ideas, the devices can be recreated, and in a better sequence that we ac…

On the other end, we might not be able to reinvent nuclear technology. Quite a bit of that was based on the Shinkolobwe mine which had 65% uranium ore deposits. These days finding 1% uranium ore is a lucky find.

That is a fascinating story. It makes fictional countries based on hidden mines, like Wakanda, seem much more plausible.

Re: Civilizational Collapse, Part 4

#125

Post by beat »

chimprich wrote: post #106
whatshisface wrote: post #74

Earlier quoted context omitted.

I'm not an expert on global agriculture, but a lot of the famous Texas cattle ranches can basically only grow grass. If the natural state of the land is brush that only goes up to your ankles you aren't going to feed much other than grazers off it. The efficient solution would be to use the good land to grow food and the rest of the land to feed livestock, and that's what tends to happen (feedlot factory farms fueled…

> the famous Texas cattle ranches can basically only grow grass Why? Anyway, wheat is a grass.

Not all grasses are equally edible. Most aren't, in fact.

Re: Civilizational Collapse, Part 4

#126

Post by mcphage »

curlcntr wrote: post #45
ddxxdd wrote: post #12

This feels reminiscent of the current issue of long-term data storage. Flash drives are volatile and can lose your data any minute. Solid State drives are slightly less volatile, and a hard disk has magnetic fields that will last decades, but nothing will keep our gigabytes of data alive and intact for future archaeologists. If the Library of Alexandria can burn, then so can any form of digital storage. On a side not…

And something else for any future intelligent species: Today, fossils are dug up and flown around the world to museums etc. We publish but if that storage doesn't last or is undecipherable, future civilizations might have an interesting adventure trying to reconstruct the world of 100's of millions of years before our time. I wonder if there has been any consideration of this or attempts at placing long-lived simple…

> I wonder if there has been any consideration of this or attempts at placing long-lived simple markings to guide?

There's a project to design and place long-lived simple markings to tell people to stay away from nuclear waste storage sites, and... it's hard problem: https://www.forbes.com/sites/jamesconca/2015/04/17/talking-t...

Re: Civilizational Collapse, Part 4

#127

Post by baybal2 »

rleigh wrote: post #83
baybal2 wrote: post #30

Earlier quoted context omitted.

A fictional universe of battletech illustrates that quite realistically. They have fusion reactors for every housewife, godlike metallurgy and rocket engines, but they can't make advanced computers no matter how hard they try after an interstellar nuclear civil war put an end to interstellar trade and, thus, complex economies and long supply chains. Such things require enormous societal organisations to work, and tha…

I think there's one key flaw in this, as well as it being fiction. There's a difference between being able to do something once or at very low volumes, and then doing it at scale for production. So long as you understand the basic principles, you could make an integrated circuit using hand-drawn acetate or glass sheets and some really simple optics. Or ignore integrated circuits and make stuff from discrete component…

> So long as you understand the basic principles, you could make an integrated circuit using hand-drawn acetate or glass sheets and some really simple optics. Or ignore integrated circuits and make stuff from discrete components which you made yourself. You only need to care about making complex EUV scanners much, much later on.

Yes, in the universe, they can easily make microelectronics on technology level of twentieth century eighties.

The main idea is that they have no hope to make anything remotely approaching even 21st century "advanced tech" level, without an actual civilisation that had few decades of peace and prosperity to allow for civilisation-wide supply chains, knowledge sharing, and economy.

Re: Civilizational Collapse, Part 4

#128

Post by philg_jr »

beat wrote: post #122
dredmorbius wrote: post #97

Earlier quoted context omitted.

The reference is to trophic levels and caloric loss. Plants, in net, capture about 1-3% of available solar energy and convert that to equivalent biomass. Food conversion -- the parts you can eat -- are a small fraction of that. Herbivores and predators each convert about 10% of the food energy they eat into body mass, for a 90% reduction (approximately) at each trophic level. Grazers lose 90% of the primary plant foo…

Technology changes that game. Grains are the core of the human diet, and have been since the dawn of civilization. But they are only edible because of civilization - the grinding, fermentation, and cooking breaking them down into something our bodies can use. In the US and other wealthy countries, we might feed grain to livestock, but it's also often parts of grain that we can't really eat (hulls, etc). And in poorer…

> When farming, the questions are even more complex. The livestock generates manure that fertilizes the fields, so much of that "lost" energy is recovered.

Which is why grassfed > cornfed in pretty much every situation except for the extra fat/flavor you might get from cornfed beef. Having cows that consume grass is a win-win. The grass absorbs sunlight instead of reflecting it back into the atmosphere like a feedlot does, the grass is digested better, and manure fertilizes the grass. And when the cows are moved to different pastures and chickens are brought in, they help to agitate the manure into the soil to help that fertilizing process along.

I wish the grassfed beef industry was embraced more instead of people attempting to swear off beef completely.

Re: Civilizational Collapse, Part 4

#129

Post by kijin »

TheOtherHobbes wrote: post #94
kijin wrote: post #22

Earlier quoted context omitted.

No, in books and journals. We're still printing them by the billions every year. Software of various kinds might be lost, since we usually don't print them out. But the theory required to re-implement them are all available on paper, sitting in a library somewhere. A book on algorithms and data structures will be far more useful to a future civilization than raw source code for a hardware architecture that won't even…

A book on software and algorithms would be useless without hardware to experiment on. There's only so much you can do with cogs and rods, so software only really starts to make sense with electronics of some kind - and only becomes useful when you have enough speed and memory to do real work. Which in turn assumes that you have real work to do. One of the earliest civilian computing systems was a payroll calculator -…

All the more reason to appreciate the general knowledge we've written into books, rather than the cutting-edge implementations that only live on computer disks. The former is much more likely to be useful to a civilization with radically different needs and available tools.

Re: Civilizational Collapse, Part 4

#130

Post by mcphage »

chimprich wrote: post #106
whatshisface wrote: post #74

Earlier quoted context omitted.

I'm not an expert on global agriculture, but a lot of the famous Texas cattle ranches can basically only grow grass. If the natural state of the land is brush that only goes up to your ankles you aren't going to feed much other than grazers off it. The efficient solution would be to use the good land to grow food and the rest of the land to feed livestock, and that's what tends to happen (feedlot factory farms fueled…

> the famous Texas cattle ranches can basically only grow grass Why? Anyway, wheat is a grass.

> Why?

Not enough water.

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