Thursday, July 12, 2012

Worldwatch Institute: Meat-Eating Responsible for More Than Half of Global Warming

Worldwatch Institute: Meat-Eating Responsible for More Than Half of Global Warming

I have had a person claim that raising cattle on pasture doesn't contribute to global warming as soon as he saw the title of the Worldwatch article, without even reading the original article, which explains that pasture land is part of the problem, when it is created by cutting down forests.
As there is now a global shortage of grassland, practically the only way more livestock and feed can be produced is by destroying natural forest. Growth in markets for livestock products is greatest in developing countries,where rainforest normally stores at least 200 tons of carbon per hectare. Where forest is replaced by moderately degraded grassland, the tonnage of carbon stored per hectare is reduced to 8.

On average, each hectare of grazing land supports no more than one head of cattle,whose carbon content is a fraction of a ton. In comparison, over 200 tons of carbon per hectare may be released within a short time after forest and other vegetation are cut, burned, or chewed. From the soil beneath, another 200 tons per hectare may be released, with yet more GHGs from livestock respiration and excretions. Thus, livestock of all types provide minuscule carbon “piggybanks” to replace huge carbon stores in soils and forests. But if the production of livestock or crops is ended, then forest will often regenerate. The main focus in efforts to mitigate GHGs has been on reducing emissions, while—despite its ability to mitigate GHGs quickly and cheaply—vast amounts of potential carbon absorption by trees has been foregone.
Much of the pasture land in the continental U.S. was once forest. Remember how all the pioneers cleared forests to create pastures and farms? More than 96 percent of the original forests covering North American have been cleared.

That means that your locally raised, grass-fed meat probably is part of the problem, not part of the solution, because it is raised on pasture that once was a forest that could, if restored, sequester 25 times more carbon than the pasture and cattle combined.

And we continue to clear forests (for various purposes, including livestock):  In fact, at present, the U.S. has a higher percentage of forest loss than Brazil.

This person also claimed that global warming is not even occuring; that we are cooler now than thousands of years ago.  In fact,  "The most respected scientific bodies have stated unequivocally that global warming is occurring, and people are causing it by burning fossil fuels and cutting down forests."

This passage from the Environmental Defense Fund page discussing the scientific consensus on global warming gives a good description of how science works to weed out mistakes:
Climate scientists, like all scientists, are professional skeptics. They welcome — in fact, rely upon — rigorous challenges to their work from colleagues. Through this process of peer review and independent verification, scientists critique and double- (and triple- and quadruple-) check each others work.
This can lead to debate and controversy, but over time, solid research is validated, errors are discarded, and a body of reliable facts is created. In addition, science advances by focusing on what is not yet known. In the case of climate change, for example, there is an extremely good general understanding of the phenomenon, but many details are not yet understood. These gaps in the research, as they come to light, are systematically tackled by the scientific community.
In this context, the kind of material used by climate-change skeptics to cast doubt on global warming — whether it be a handful of emails stolen from an East Anglian research facility or a few errors in an IPCC report — are meaningless. The mountain of climate data assembled over decades by the scientific community as a whole is irrefutable. The records collected and analyzed by independent scientists from many disciplines and thousands of locations, paint a consistent, verifiable picture of a rapidly warming world.
Make no mistake: Science has given us unequivocal warning that global warming is real. The time to start working on solutions is now.
This passage equally applies to medical nutrition science.  I will only substitute a few appropriate bolded words in the above passage:


Medical and nutrition scientists, like all scientists, are professional skeptics. They welcome — in fact, rely upon — rigorous challenges to their work from colleagues. Through this process of peer review and independent verification, scientists critique and double- (and triple- and quadruple-) check each others work.

This can lead to debate and controversy, but over time, solid research is validated, errors are discarded, and a body of reliable facts is created. In addition, science advances by focusing on what is not yet known. In the case of diet and heart disease, for example, there is an extremely good general understanding of the phenomenon, but many details are not yet understood. These gaps in the research, as they come to light, are systematically tackled by the scientific community.

In this context, the kind of material used by lipid hypothesis skeptics to cast doubt on the lipid hypothesis — whether it be a 1935 book by a dentist, a set of pre- World War II studies, or a blogger's mishandling of the raw China Project data — are meaningless. The mountain of nutrition data assembled over decades by the scientific community as a whole is irrefutable. The records collected and analyzed by independent scientists from many disciplines and thousands of locations, paint a consistent, verifiable picture of diets rich animal protein and fat promoting disease.

Make no mistake: Science has given us unequivocal warning that diets rich in animal protein and fat promote disease. The time to start changing your diet is now.

I find it interesting to see how nutrition science denial seems to go hand in hand with climate science denial, and vice versa.

Ignorance seems like bliss, until it isn't.

Sunday, July 1, 2012

Study: Autralopithecus Diet "Almost Exclusively" Plant Food – Researcher Says "Humans Are Basically Grass-Eaters"

Australopithecus Sediba Preferred Forest Foods, Fossil Teeth Suggest - NYTimes.com

New research on the diet of Australopithecus Sediba has revealed another beautiful fact undermining the ugly Paleo DietTM theory.  This recently discovered  possible human ancestor that lived about 2 million years ago appears to have eaten an "almost exclusively" plant-food diet:
"Almost two million years after their last meals, two members of a prehuman species in southern Africa left traces in their teeth of what they had eaten then, as well as over a lifetime of foraging. Scientists were surprised to find that these hominins apparently lived almost exclusively on a diet of leaves, fruits, wood and bark." 
This NYT article discussing the research contains an interesting comment from Benjamin H. Passey, a geochemist at Johns Hopkins University, who conducted the tests determining the high ratio of carbon isotopes indicating a diet mostly of plant foods:

"“One thing people probably don’t realize is that humans are basically grass eaters,” Dr. Passey said in a statement. “We eat grass in the form of the grains we use to make breads, noodles, cereals and beers, and we eat animals that eat grass. So when did our addiction to grass begin? At what point in our evolutionary history did we start making use of grasses? We are simply trying to find out where in the human chain that begins.”"[Emphasis added]

It doesn't look like anyone presenting at the upcoming 2012 Ancestral Health Symposium will be discussing the reality that humans evolved as primarily plant- and probably, grass-product eaters.  In fact, it looks like someone there considers plants "A Little Shop of Horrors."  Sigh. 
 
Science like this shows that so-called "Paleo diet" advocates are way off track if they still think that grains, i.e. seeds of grasses, are only a recent addition to the diet of humans.  The idea that an almost purely carnivorous species with no experience eating grass seeds just suddenly adopted a grain-based diet only 10K years ago, after more than 2 millions of years completely grain-free, simply strains credulity.

Put otherwise, the agricultural revolution must have been preceded by a long, increasingly symbiotic relationship between human ancestors and seed-bearing grasses. Although ancestral humans did  consume variable quantities of meat, meat-consumption probably did not provide the key to human brain expansion or significantly alter human physiology from its baseline adaptation to a plant-based diet. 

This new research reminds me of my June 19, 2011 post entitled "Gathering Wild Grains,"  wherein I wrote

"Put this together with evidence that Paranthropus boisei, a human relative dating to 1.4 to 1.9 million years ago,  grazed on grass [2].  Paranthropus and humans both descended from Australopithecus, but the Paranthropus went extinct.  To several scientists working with this information, this new data on Paranthropus suggests a reinterpretation of previously collected data on Australopithecine diet, i.e. that Australopithecus may also have eaten grasses.

"Perhaps we can start to put together a plausible path for the incorporation of cereal grains--grass seeds--into human diets.  Perhaps human ancestors used grasses as food more than 2 million years ago. Human evolution might look something like this: the grass-eaters went extinct, but the grass-seed eaters thrived."
-->I am now even more confident that a grain-based, legume-enhanced diet is likely more ancestral than the Paleo DietTM .  To celebrate, I am going to eat a big bowl of grass seeds and fruits, topped with legume milk, as soon as I finish this post.

http://www.peta2.com/stuff/veganMenuImages/1-friBfast-cereal.jpg
Cheers!