< 350ppm CO2 : Where we need to aim

[chuckm]

I seriously question assertions 1 and 3. I don't have any reason to doubt 2. I'd put a huge asterisk on 4.
1) Typically about 80% of the paleolithic diet came from gathering. Gathering sufficient food to provide about 900 digestible calories per day, with enough variation to provide all the required nutrients probably took more than 2 hours, especially during winter. Hunting with primitive weapons is a dubious thing (anybody here ever tried to hunt with a spear? a bow and arrow made from sticks, a stone, and plant-fiber twine?) and probably involved much more than 2 hours a day and had a low success rate.
3) The sources I've found put paleolithic life expectancies between 33 and 54 (if you made it past 15 years old, you had a good chance of making it to 39-54). In the neolithic, life expectancy was about 20. Could you point me to your source?

The above ONLY apply to those who were strictly hunter gatherer, not the hybreds like native americans who tended to also farm on the side.

The problem with that is that paleolithic populations were processing cereal grains for food some 23000 years ago, with evidence suggesting as early as 200,000 years ago (Piperno, D; Weiss, E., Hols, I., Nadel, D (2004), 200,000 years from People, Plants and Genes: The Story of Crops and Humanity. Oxford: Oxford University Press.). Everybody would be, as you termed it, a hybrid.

FYI, both the American Dietic Association and the National Health Service of England have designated the "Paleolithic diet" (aka caveman diet) as a fad diet.

[rmay635703]

Actually 3 is still true assuming that they don't die from some sort of brute force or starvation. The longest lived peoples on the planet also live the most simplistically. And that tends to be regardless of whether its meat or vegetable. There are many examples of 60/70+ year old individuals from tropical basin hunter gathers.

1. is also true when you limit it to our origins in the tropical basin, people generally didn't survive into the cold blue yonder as hunter gathers.

4. Is almost always true when comparing a traditional diet to a grain based diet. The diet of wheat that has been pushed down our throats was historically proven to be the worst as exemplified by the Egyptian culture.

The low sucess rate now can be attributed to us having a vastly different world than of many years past, with very few people and lots of animals, especially in the the tropical basin, hunting would not be difficult and would not occupy all of your day since a little cooperation can net one larger animal feeding the group. Our ancestors DID NOT start in the cold barren wasteland but in regions where they could live near naked.

The lifespan averages again typically involve a lot of speculation and a lot of deaths due to being killed by something or falling or whatever. Historically men were killed by something other than old age.

Originally Posted by chuckm

I seriously question assertions 1 and 3. I don't have any reason to doubt 2. I'd put a huge asterisk on 4.
1) Typically about 80% of the paleolithic diet came from gathering. Gathering sufficient food to provide about 900 digestible calories per day, with enough variation to provide all the required nutrients probably took more than 2 hours, especially during winter. Hunting with primitive weapons is a dubious thing (anybody here ever tried to hunt with a spear? a bow and arrow made from sticks, a stone, and plant-fiber twine?) and probably involved much more than 2 hours a day and had a low success rate.
3) The sources I've found put paleolithic life expectancies between 33 and 54 (if you made it past 15 years old, you had a good chance of making it to 39-54). In the neolithic, life expectancy was about 20. Could you point me to your source?


The problem with that is that paleolithic populations were processing cereal grains for food some 23000 years ago, with evidence suggesting as early as 200,000 years ago (Piperno, D; Weiss, E., Hols, I., Nadel, D (2004), 200,000 years from People, Plants and Genes: The Story of Crops and Humanity. Oxford: Oxford University Press.). Everybody would be, as you termed it, a hybrid.

FYI, both the American Dietic Association and the National Health Service of England have designated the "Paleolithic diet" (aka caveman diet) as a fad diet.

[chuckm]

The following is a PM I sent to NeilBlanchard in response to his post.

Regarding the first Apteraforum post: I fully acknowledge that temperatures from ca. 1880 have increased. However, it should be noted that earth was just coming out of the "Little Ice Age." One should hope that temperatures since then have increased! Lookup the following: the Maunder minimum, the Irish famine of 1740-41, the year without a summer (1816 BTW, when the already below average temps were further impacted by a massive volcanic eruption). WRT the Little Ice Age, global warming was a GOOD thing.

It's not that I'm better educated than Hansen... I'm not. I do not pretend to be a climatologist. I do not think I've put on airs like I am one... but I am not utterly unable to read a scientific paper or read a graph of the data. In that regard, can you find fault with the facts I've presented? I know you disagree with my conclusions, but are the facts I've presented erroneous?
For example, is it a fact that, in the past 400,000 years, it has been warmer on several occasions?

Is it a fact that temperatures during the Holocene Climatic Optimum was warmer than present?


Is it a fact that the Medieval Warm Period had temperatures comparable to the present 10 year averages?


Was I incorrect regarding the 8.2k event, mentioned in one of my posts? Was I in error regarding the relative impacts of the various greenhouse gases?

I think Hansen is disingenuous in representing 260-270ppm as "normal," considering that CO2 concentrations have, in earth's history have been much higher. What's normal? The Devonian period had mean CO2 levels of 2200ppm. The Carboniferous period had mean CO2 levels of 800ppm. The Permian: 900ppm. The Triassic: 1750ppm. The Jurassic: 1950ppm. The Cretaceous: 1700ppm. The Paleogene seems to have ranged from 1000-1500ppm. Only in the pre-modern human Neogene and Quaternary periods do we see CO2 drop into the 280ppm range. Interestingly, some of the Neogene and much of the Quaternary is also dominated by glaciation. Thus, what Hansen is defining as "normal" is glaciation. The current temperatures and global ice volumes, however, are not much different than other interglacial periods (see ~125,000, ~300,000, and ~400,000 years ago and, to a lesser extent 200,000 years ago).

[chuckm]

Actually 3 is still true assuming that they don't die from some sort of brute force or starvation. The longest lived peoples on the planet also live the most simplistically. And that tends to be regardless of whether its meat or vegetable. There are many examples of 60/70+ year old individuals from tropical basin hunter gathers.

1. is also true when you limit it to our origins in the tropical basin, people generally didn't survive into the cold blue yonder as hunter gathers.

4. Is almost always true when comparing a traditional diet to a grain based diet. The diet of wheat that has been pushed down our throats was historically proven to be the worst as exemplified by the Egyptian culture.

Could you help me with some sources? Thanks!

The low sucess rate now can be attributed to us having a vastly different world than of many years past, with very few people and lots of animals, especially in the the tropical basin, hunting would not be difficult and would not occupy all of your day since a little cooperation can net one larger animal feeding the group.

Actually, humans typically have done more to decimate predator populations, meaning an over-abundance of prey animals. Check out the populations of white-tailed deer in North America... or on your bumper. Besides, wouldn't evolution tend to kill off easy prey before humans even came into the picture? I don't think gazelles became tremendous runners in the last 20,000 years.

Historically men were killed by something other than old age.

Agreed. Disease often did the trick too. But again, if you could point me to some sources that support your assertion, it would be very helpful. Thanks again.

[jamesqf]

Originally Posted by chuckm

Hunting with primitive weapons is a dubious thing (anybody here ever tried to hunt with a spear? a bow and arrow made from sticks, a stone, and plant-fiber twine?) and probably involved much more than 2 hours a day and had a low success rate.

Opinions differ on that, for instance The Atlatl and Dart: An Ancient Hunting Weapon

You need to keep in mind that things like hunting become much easier when you practice the skills continuously, rather than for a couple of weeks in hunting season.

[chuckm]

The effective range of the atlatl was about 20-30 yards (accuracy and penetration) for thin-skinned mammals. Perhaps 40 yards with a very well made one (dowel-like straight pieces of wood simply don't fall off trees, so these were probably exceptionally rare).
Again, my point is simply that I seriously doubt that 2 hours of hunting could consistently provide meat. If it were that easy, why would neolithic man tie up valuable time and resources by working to domesticate cattle and protect them from predation?
FYI, pastoralism (nomadism + herding) is a typical intermediate state between agrarianism and nomadism.

[jamesqf]

Originally Posted by chuckm

Again, my point is simply that I seriously doubt that 2 hours of hunting could consistently provide meat.

The claim re hunter-gatherer cultures is that about 2 hours a day was/is devoted to gathering food, not necessarily meat. Even here & now, it wouldn't be impossible for someone with the knowledge, especially given the great number of quite edible things that we seldom if ever eat.

If it were that easy, why would neolithic man tie up valuable time and resources by working to domesticate cattle and protect them from predation?

To have something to do with all that free time :-) But if you look at the history of domestication, the first domestic animals - dogs, then horses - were probably aids to hunting. Then other animals seem to have been kept as much for milk & wool as for meat.

[chuckm]

But if you look at the history of domestication, the first domestic animals - dogs, then horses - were probably aids to hunting. Then other animals seem to have been kept as much for milk & wool as for meat.

In other words, these were enhancements in resource availability and security over simple nomadic hunting-and-gathering.

Even here & now, it wouldn't be impossible for someone with the knowledge, especially given the great number of quite edible things that we seldom if ever eat.

I don't disagree, but food availability also varies significantly by region. But would 2 hours of gathering provide for a diet with sufficient caloric and nutritional intake?

Where DOES this 2 hour figure come from anyway? If it is from Sahlins' Notes on the Original Affluent Society, you ought to know that the studies he relied on weren't exactly exhaustive, limited in both scope and duration.

So, anyway, I still think Hansen's figure of 350ppm is not well grounded in scientific fact. I also think his citing 280ppm as "normal" is lacking in context. Don't get me wrong, though; I do believe that we have a moral responsibility to develop and implement clean, efficient and cheap energy sources. But I think that the climate alarmism that Hansen is promoting is ultimately destructive to the cause.

[jamesqf]

Originally Posted by chuckm

Where DOES this 2 hour figure come from anyway? If it is from Sahlins' Notes on the Original Affluent Society, you ought to know that the studies he relied on weren't exactly exhaustive, limited in both scope and duration.

I don't really know. I've seen the figure in various articles, but I don't make a .bib file for my casual reading :-) But there are other accounts of the life of e.g. the various Plains Indian tribes, or the California ones, which certainly support the idea that it wasn't exactly a hand-to-mouth existence.

So, anyway, I still think Hansen's figure of 350ppm is not well grounded in scientific fact. I also think his citing 280ppm as "normal" is lacking in context.

I have to agree on the 350 ppm figure, but from the opposite direction. Though it might be tolerable, t's probably too high to allow for a pleasant climate. I'm for 280 at a max - but then I think an ice age might well be an improvement on present conditions. FTM I'd even like to go back to conditions in the late '70s & early '80s, when ski season usually started in October. Some of the immigrants (I regard Californians as immigrants) have complained about this year being cold, but I was out cutting firewood at about 7500 ft yesterday, in a T-shirt.

[chuckm]

I have to agree on the 350 ppm figure, but from the opposite direction. Though it might be tolerable, t's probably too high to allow for a pleasant climate. I'm for 280 at a max - but then I think an ice age might well be an improvement on present conditions.

Define pleasant climate... I can tell you that my definition doesn't involve ice ages, resulting in mass starvation, lower biological productivity and such. Honestly, a real return to ice age condition could well wipe out 2 or even 3 billion people.

I'd even like to go back to conditions in the late '70s & early '80s, when ski season usually started in October.

I like skiing too. But you do know that back in the 70s, Time had a magazine cover proclaiming climate alarmism of a different form - global cooling. The cover showed an iced over earth, IIRC.