Sunday, October 31, 2010

Vegans Autocomplete Me

This post is an attempt to get a glimpse at people's stereotypes of vegans by using Google's autocomplete feature. By better understanding how people feel about vegans, we can better counter these stereotypes and open people up to considering the more important aspects of our animal rights message.















Looking through all of these I'd say the most common stereotypes are that vegans are weak, unhealthy, and annoying. In particular protein deficiency still seems to be a major misconception in addition to the idea that we are all skinny and pale. The idea that vegans are angry and gassy doesn't seem to be unusual either.

There is one bit of good news however. Apparently we can read minds.

Nuclear Energy

Nuclear energy actually describes two different types of energy, fission and fusion. Nuclear fission is the form already in use, while no nuclear fusion power plants yet exist. Nuclear fission is the process of splitting heavy atomic nuclei, such as uranium, plutonium, or thorium into lighter products, turning a small amount of the mass into energy in the process (associated with the nuclear binding energy of the nuclei). Nuclear fusion involves combining lighter atomic nuclei into heavier ones, retrieving a small amount of the mass as energy once again. As a general rule, fission releases energy for nuclei much larger than iron, while fusion releases energy for nuclei much smaller than iron.

Energy Potential

Nuclear energy is unlike most sources of energy that are considered renewable, because in any given year we are able to extract as much energy from it as we choose to use in fuel. Nuclear energy isn't limited by the amount of solar radiation falling on the surface, the speed the winds blow, or the amount of rain that falls. The limiting factor is the amount of material available to be used in nuclear reactions.

Fission

Uranium

Uranium has two isotopes currently used to produce energy from nuclear fission. The first of these, uranium-235 makes up only about 0.7% of worldwide uranium, but can be used much more easily. The second isotope of uranium, U-238, can be turned into plutonium-239 within fast breeder reactors, which can then extract about 60 times as much energy from the same amount of uranium ore.

Uranium is currently mined from uranium ores. There are presently about 4.7*10^9 kilograms of uranium stored in these ores, enough at our present rate of use of just nuclear energy to last us a mere 85 more years according to the International Atomic Energy Agency. If we started exclusively using fast breeder reactors however, this same supply of uranium could provide the same power output for over 2500 years.

Much more uranium is stored in phosphates; an estimated 3.5*10^10 kilograms. Accessing this would come at a few times the cost of mining uranium ore, but since the cost of the fuel is such a tiny fraction of the cost of running a nuclear power plant, fuel extraction costs can afford to increase several times without causing a significant increase in the price of the electricity we receive.

The vast majority of the world's known uranium is stored in the oceans however. A total of 4.5*10^12 kilograms exists dissolved in our sea water, enough, if used in combination with fast breeder technology to continue current nuclear energy production for nearly 2.4 million years. Extracting uranium from sea water has been done in the past; however, never on an industrial scale, most likely due to the lack of economic incentive at current uranium prices.

Nuclear energy only accounts for 5.8% of the world's present energy supply. If we wished to replace the energy from all sources with energy produced from fast breeder reactors, the world's known uranium resources could last roughly 140,000 years.

Thorium

The other major fuel currently used in fission reactors is thorium. Thorium reactors are similar to fast breeder reactors, but rather than turning uranium-238 into fissile plutonium-239 they turn thorium-232 into the fissile uranium-233. Known worldwide thorium reserves which are easily recoverable amount to 2.6*10^9 kilograms. Using this easily recoverable thorium with current reactor technology, this could supply all world energy demand for roughly 66,000 years.

Fusion

Fusion is the form of energy that powers our sun. Currently fusion reactions have been done in lab conditions on earth, and energy has been gathered from these reactions, but the energy put into starting these reactions has always been greater than the energy recovered. In 2008 construction began on an international project, ITER, that hopes to be able to sustain a fusion reaction with an output of 500 million watts (Joules per second) for at least 1000 seconds at a time with an energy input of only a tenth of this amount. ITER plans to react deuterium and tritium creating helium and energy as its product.

Deuterium is a naturally occurring isotope of hydrogen, and about 33 grams of deuterium can be found in every ton of water. Tritium does not occur in large quantities naturally, but is made from lithium. The amount of lithium is the limiting factor in this reaction, so we will investigate its total potential.

According to the USGS, “The identified lithium resources total 760,000 tons in the United States and more than 13 million tons in other countries.” This is much less than the estimated 230 billion tonnes that are dissolved in our oceans. A reasonable estimate for energy gained per kilogram of lithium would be around 8*10^12 Joules. Assuming this technology pans out, this would mean nearly 2*10^27 Joules of potential energy, or enough to replace earth's current supply for 3.7 million years.

The deuterium-tritium reaction is not the only one which has been proposed. Deuterium-deuterium is a reaction that has been thoroughly tested in the past although also not yet implemented. For this reaction energy output is roughly 3.5*10^14 Joules per kilogram of deuterium. With about 2.4*10^16 kilograms of deuterium in our oceans, this would mean roughly 8.3*10^30 Joules, or enough to replace our current rate of supply for 16 billion years. This is longer than the current age of the universe and well past the anticipated death of our sun. We can only assume we will be able to harness a fraction of this energy, but this is an energy source with billions of years of potential in any case.

Dangers

Meltdown

Much public fear exists over the potential for a nuclear meltdown. This public fear isn't entirely misplaced as a full scale nuclear meltdown has happened in the past in Chernobyl,Ukraine, and another near meltdown at Three Mile Island in Pennsylvania.

Chernobyl

Fission reactors generate large amounts of heat even when they are not producing electricity, and the Chernobyl nuclear facility required coolant to be flowing at all times even when not generating electricity. In the case of a power outage, three generators would come online in order to keep coolant flowing. Starting these generators up took 15 seconds, and they took an additional 60-75 seconds to reach their full operating capacity. This was thought to be unacceptable, and thus it was proposed that the energy remaining in the plant's steam turbines could be used to power the coolant pumps for roughly 45 seconds while the generators started up. The reactor went online in 1983 without this system being tested successfully.

On April 25, 1986 conditions were planned to run the test at last. The day shift had been instructed on how the test was going to proceed, and the reactor had reduced its power output in the early morning on April 26. However, another power plant unexpectedly went offline that day and the Chernobyl reactor was ordered to return to full output. At around 11PM, the reactor was allowed to reduce its power output once again. The day shift had long since departed at this point, and the night shift was given little opportunity to prepare before being thrust into this test.

The reactor was supposed to be turned down to 700 million watts of power, but the production of neutron absorbing xenon in the reactor core caused the power to continue to fall down to roughly 500 million watts. The senior engineer overseeing the experiment then inserted the control rods into the reactor core much too far causing the power to drop to a mere 30 million watts.

When the control room finally decided to restore power, it took several minutes for power generation to begin to rise again, and it stabilized at roughly 200 million watts of output due to the amount of xenon that had accumulated during this time. At this point the control rods had been maximally withdrawn from the reactor core.

After the reactor power had stabilized near 200 million watts for some time the engineers decided to increase water flow through the reactor as part of the test, despite this being well below the intended test conditions. Increasing water flow dropped the power output of the reactor once again, causing the controllers to manually remove control rods from the reactor in an attempt to restore power.

It was under these conditions that the test began. Steam to the turbines was shut off and the water coolant was pumped using the energy remaining in the generator. As the generator slowed however the coolant began to flow more slowly, allowing more of it to boil and decreasing its ability to cool the reactor causing the reactor to heat more and boil more of the coolant.

The system handled this situation quite well actually, reinserting control rods to handle the increase in temperature. As the test was winding down, the emergency shutdown for the reactor was manually initiated, possibly as an attempt to turn off the reactor after the experiment. The system took several seconds to fully insert the rods however, which were poorly designed with graphite tips, causing them to displace coolant before inserting the neutron absorbing material.

As this happened the core power spiked, with none of the usual control rods in, little to no coolant flowing and steam already decreasing the efficacy of the coolant. Under high pressure steam exploded, fracturing some of the control rods and preventing others from inserting properly. A few seconds later a full nuclear meltdown occurred exploding a significant portion of the facility and causing the remainder to burn for several days.

In addition to having gone online without the proper safety tests having been conducted, the facility was in non-compliance with numerous standards of the time for nuclear facilities, most importantly the positive feedback the steam had on the core temperature, and the improper design of the control rods.

This full scale meltdown occurred at one of the world's largest nuclear facilities and represents the worst possible scenario for any nuclear power malfunction. In addition to the 57 direct deaths as a result of the accident, it is estimated that the total number of deaths attributable to this incident could amount to several thousand.

Several thousand deaths is a tragedy without a doubt, but it is on par with estimates for the deaths attributable to the pollution emitted from coal power plants alone every single year. In relation to power output, nearly all estimates put nuclear energy as one of the safest energy sources regarding its cost in human lives.

Spent Fuel

The radiation from the fuel itself isn't the main concern when dealing with spent nuclear fuel. The fuel was mined out of the earth in the first place and it would be hardly any effort to dilute it down to its original concentration and dispose of it underground. The main concern is the radiation from shorter lived isotopes created as products of the fission reaction. If uranium-238 with a half life of 4.5 billion years is split into two smaller isotopes each with half lives of 4.5 million years, then the expected rate of decay at present will have increased 2000 fold (although the type of radiation emitted may have changed). Many of the fission products have much shorter half lives, and once spent fuel has been allowed to cool for a few decades only a tiny fraction of the original radioactivity remains.



Within roughly a thousand years, the radioactivity of the spent fuel is no higher than that of the original ore.



Conclusions

Nuclear energy is by far the cheapest energy source with the potential to replace fossil fuels in the long term. It also has the ability to keep up with a growing population and an increasing standard of living. If we wish to make nuclear power last in the long term, more sustainable fast breeder technologies will need to be adopted on a large scale, but eventually nuclear fusion technology will need to be explored. Current projects such as ITER and its proposed successor DEMO show a great deal of promise, but have yet to become realities. If these technologies pan out as hoped, we may finally have found a solution to long term energy independence.

Additional Reading

Sustainable Energy — without the hot air

Combustible Renewables and Waste – Biomass

This category of our energy supply describes a huge array of different energy sources, which makes putting figures on their potential growth more difficult. The International Energy Agency describes this category of being composed of liquids from biomass, industrial wastes, municipal wastes, and solid biomass and animal products.

Liquids from Biomass

This category includes landfill gas, gasses from sewage and animal slurries (manure lagoons), as well as the much hyped ethanol.

Landfill, Sewage, and Slurry Gasses

All of these gasses involve the capture of methane produced by anaerobic bacteria feeding in these conditions and then burning this methane to produce energy. According to the EPA total methane emissions into the atmosphere from all sources amount to 5.66*10^11 kilograms per year. Combustion of methane releases roughly 5.55*10^7 Joules per kilogram burned. This means even if we were able to capture all of the methane leaking into the atmosphere around the world this would amount to 3.1*10^19 Joules per year, or 6.2% of the world demand. Capturing methane might make sense in some situations, but it does not have large scale potential.

Ethanol

Ethanol is the same alcohol found in the alcoholic beverages we consume. It is produced from the fermentation of a number of foods, primarily corn, but also sugarcane, other cereals, and more recently even cellulose. These plants gather energy from the sun, so in a sense ethanol production is an inefficient, but convenient form of solar power collection.

Measuring the energy gained from producing ethanol is very difficult to determine due to all the factors that go into producing it: energy to use the farm equipment, energy to produce fertilizers, energy to transport crops, energy to refine the ethanol. Partially due to the large extent the United States has been pushing ethanol fuels, a great deal of effort has been put into calculating this energy gained from ethanol.

Early studies on producing ethanol from corn were unclear as to whether there was any net benefit, putting it somewhere between a couple times more energy produced, down to significantly less energy gained than originally used to produce the ethanol. It now appears that producing ethanol from corn has a marginal benefit of somewhere between 6% and 67% more energy extracted from the ethanol than was used to produce it. One study on biofuels soberly put the case as, “The picture for ethanol from corn is particularly depressing. The entire global harvest of corn (700 million tons) converted to ethanol with current technology would yield enough transportation fuels to supply only 6% of the global gasoline and diesel demand.” Gasoline and diesel for transport being only a fraction of the world's overall energy use.

The outlook for producing ethanol from sugarcane has a much better outlook than corn, producing somewhere in the range of 8-10 times as much energy as is used to produce it. Nonetheless, our overall potential from all ethanol fuels is still quite small as the previous biofuels study notes, “Converting 100% of the global harvest of corn, sugarcane, soy and palm oil into liquid fuels, using the current technology, would provide fuel energy of 3% of global primary energy from fossil fuel combustion and net energy (after subtracting the energy required to produce the fuels) of 1.2% of the global primary energy from fossil fuel combustion.” Converting all of our major food crops into ethanol still only has the potential to replace a small fraction of our fossil fuel dependence.

Industrial and Municipal Wastes

Both of these are comprised of burning the solid and liquid wastes which would otherwise be thrown away. If we assume that municipal trash in Denmark is fairly typical of the energy content of wastes around the world then incineration of waste yields roughly 1.05*10^7 Joules per kilogram.

No worldwide figures exist for total garbage production, but the United States Environmental Protection Agency estimates that 2.3*10^11 kilograms of garbage is thrown away in the United States each year. Considering both the proportion of greenhouse gas emissions that come from the United States and the percentage of the world's population that lives there, I think a reasonable estimate for the world total would be 10-20 times the US total. Taking the most optimistic of all our assumptions, this still yields a maximum energy potential from burning wastes of about 4*10^19 Joules or less than 10% of the world's current demand.

Environmental Impact

The incineration of municipal and industrial wastes used to contribute a significant number of pollutants into the environment. Newer standards for cleaning the flue gasses combined with newer technologies have turned incineration from one of the dirtiest energy forms to one of the cleanest. The United States Environmental Protection Agency estimates that dioxin emissions from incineration are 1/1000 of their levels in 1987. Emissions of many other pollutants have also decreased by upwards of 90%.

Solid Biomass and Animal Products

This category involves the direct burning wood or other plant matter for fuel or turning it into another form before burning it for fuel. Also included in this category is the burning of animal products or wastes; although this is not a significant source of energy. At present, the burning of wood and other plant materials is still a significant source of heat for warmth as well as cooking especially in developing countries.

Burning these fuels directly is much dirtier than turning it into cleaner fuels such as ethanol, and it has little more energy potential at this stage.

Powering Our Future

Concern over the environmental impact of energy production has been rightfully high in recent years. In deciding how we are going to provide energy in the future, we need to consider how much energy we are going to be able to provide and at what cost it is going to come, cost being both environmental and financial.

The Present Situation


As our population has continued to grow and we adopt wealthier standards of living over time worldwide energy consumption has continued to increase accordingly. As of 2008 worldwide energy production was 5.1*10^20 Joules (4.9*10^17 Btu). For those of you not familiar with these units, a typical 60 Watt light bulb uses 60 Joules of energy every second. This world total does not include only electrical energy, but also energy used to drive our cars, heat our homes or perform any number of other tasks. As of 2008 Oil accounted for 33.2% of our energy production, Coal 27.0%, and Natural Gas an additional 21.1%. The next largest source of energy production comes from the combustion of biomass (wood and other plant materials) and other wastes both municipal and industrial, accounting for 10.0% of energy production. Next we have Nuclear energy accounting for 5.8% of production and Hydroelectric energy accounting for another 2.2%. The remaining 0.7% of our production is the amount currently produced by all of the other methods we currently hear about; the sum total of all our efforts for renewable energy.



Check out the International Energy Agency's 2010 Key World Energy Statistics report for additional information on our present situation.

Future Challenges

Our three main energy sources at present are problematic for a number of reasons. Most obviously, they are all finite and at present use rates are each going to run out between a few decades and a few millennia from present. Extracting each of them will become increasingly difficult in the future as the more easily accessible sources of each become depleted.

More importantly perhaps, each of these make a huge contribution to anthropogenic global warming. Our atmosphere is transparent in the visible and near-visible parts of the electromagnetic spectrum. Our sun emits electromagnetic radiation including the light we see because it has a temperature. At it's surface temperature of roughly 5800K most of the light it emits is in the part of the spectrum where our atmosphere is transparent. The earth's surface temperature of roughly 300K emits virtually all of its energy as radiation in the infrared portion of the spectrum. Carbon dioxide and other greenhouse gasses are opaque in the infrared portion of the electromagnetic spectrum and thus absorb a great deal of radiated energy from the earth's surface once again. The burning of each of our three main fuel sources is the largest anthropogenic source of carbon dioxide.

Finally, the burning of coal in particular emits quite a large amount of particulate matter and a number of other pollutants into the atmosphere which can be detrimental to health in excess.

Replacing these means replacing the energy they provide. Not merely the electrical energy generated from these sources, but we need to be able to replace the energy used to drive our cars, heat our homes, fuel our stoves, build our products, and transport our goods as well, which largely comes from these three main sources.

There are a number of energy alternatives to these three main sources which have been proposed. A great deal of effort has been put into making many of these a reality, but they still have seen little success in replacing our present system of production. Some of them, such as cold fusion or perpetual motion are nothing other than magical thinking, but many others have actual potential for energy generation and have even been put into place to some extent. This post is going to attempt to look at the several most realistic of these sources in particular assessing both their potential costs and their potential for energy generation.

Hydroelectric

After biomass and nuclear energy, hydroelectric energy is the only remaining energy source with any significant implementation to date. Hydroelectric energy comes from the potential energy water (or any mass) has when in a gravitational well. This energy can be calculated by multiplying the mass by the force of gravity by the distance the mass is moving in the direction of the gravity force. If we wish to calculate this energy in Joules for a mass on earth we would use 9.8 (m/s/s) as the value for gravity and the distance in meters that the mass of water in kilograms is traveling up or down. Assuming that a typical area of land has 80cm of rain a year falling at a mean altitude of 100 meters, this would equal roughly 1.2*10^20 Joules of energy per year for the entire landmass of the earth, still only a fraction of the supply we need to replace. Additionally, it is obviously unrealistic to expect us to be able to capture every bit of potential energy from when a water drop lands anywhere on land until it reaches sea level. More realistically the best hydroelectric resources have already been utilized and there is only marginal room for growth potential in this area.

Solar

One of the positive aspects about hydroelectric energy was that when water is held behind dams, it can be released to generate electricity as there is demand for it. One problem that comes with adopting solar-heavy energy generation is that we are only able to generate energy as it comes in. This means we need to find ways to store sufficient energy during the day to supply our needs at night and sufficient energy during the summer to supply our needs during the winter as well.

At the earth's distance from the sun, solar radiation amounts to roughly 1367 Watts (Joules per second) for every square meter of surface perpendicular to the direction to the sun. This varies by about 50 Watts per square meter over the course of the year due to the earth's slightly eliptical orbit and by roughly half a Watt per square meter over the course of the 12 year solar cycle.

Not all of this light makes it through our atmosphere and earth, as a rotating sphere, doesn't have all of its surface perpendicular to the direction to the sun. A good area of desert at low latitude can expect somewhere around 300-350 Watts of energy to reach every square meter of surface. Solar power doesn't need to include only solar electrical generation, it is currently used in many areas for heating hot water as well as homes.

When it comes to generating electricity from heat we cannot achieve anywhere near full conversion. The finest solar cells we are able to assemble in labs are able to achieve slightly over 40% conversion efficiency at present. A typical multicrystalline silicon cell someone might install on their roof however would probably be able to achieve between 14% and 19% efficiency. Large solar power generating facilities often use parabolic reflectors to focus light on a single small area which is then usually able to achieve around 35% efficiency.

As of 2008 Solar energy accounted for less than 0.02% of the world's total energy production. This is likely due to the high costs of installing solar cells compared to other technologies and the accordingly higher costs for the electricity generated (usually a few times that of most other technologies Source. Solar energy, however, does at least have the potential to meet the world's present demand for energy if we were able to build the required infrastructure. Assuming we are using 18% efficient solar cells in an area receiving 300 Watts per square meter of energy from the sun, we would need to cover 3*10^11 square meters with these cells in order to meet the world's demand. This is almost exactly equal to the area of the US state of Arizona (and covering their entire state with solar cells sounds about as reasonable as the “birther” and illegal immigration legislation they've passed this year).

Wind

At present, wind power accounts for approximately 0.24% of worldwide energy generation. Wind power is even less reliable than solar, depending entirely on wind conditions to determine the energy it generates. Accordingly if we are going to adopt an electrical grid dependent upon wind power we need to be able to find ways to store energy for possible multiple week periods of calm winds.

A 2005 study from Stanford University attempted to estimate the world potential energy generation from wind power by attempting to measure wind speeds around the world at the height of a modern large wind turbine. Assuming all of the world's windy land or near-land areas were covered with massive 80 meter high, 77 meter diameter wind turbines, the authors estimate wind could provide 2.3*10^21 Joules or roughly 4.5 times the world's current energy needs.

Achieving this potential would require massive engineering well beyond anything ever completed before. Each of these 77 meter diameter wind turbines towers into the air roughly as high as a 38 story building. Most of this potential does not exist on land, but rather offshore where building challenges become much greater and costs also skyrocket.

Geothermal

Roughly 1.4*10^21 Joules of energy flows out through the earth's crust from the mantle each year. This represents roughly 2.7 times the planet's present energy demands. Of this, roughly 2/3 is replaced by radioactive decay. The difference between these two values is due to the huge amount of energy left over from the accretion of our planet.

Most of this energy can not be reasonably harnessed. Part of this is because most of the planet is underwater and also because most areas have very small amounts of geothermal energy coming up through the crust. The most optimistic estimates for how much energy we could ever expect to extract from geothermal power is roughly 8.0*10^19 Joules per year or roughly 17% of our worldwide demand. More sober estimates for the potential of geothermal are as low as 2.2% of present worldwide demand.

Wave

Waves are generated by winds blowing across large open bodies of water such as our oceans. The energy in wave power depends upon the square of the wave height and the frequency of the waves.

Estimates from the International Energy Agency for the total energy available in wave power vary widely from 3*10^19 Joules per year to 3*10^20 Joules per year. The World Energy Council estimates the wave resource as at least 6*10^19 Joules per year. Overall these estimates range from 6% to 60% of our present supply. Harnessing all of this resource would mean covering all of our coastline or an equivalent region of open sea entirely with wave collectors.

Tidal

Tidal energy is, in my opinion, the most fascinating of our proposed energy sources. Tides are generated by the gravitational pull from the moon (and partially the sun as well). Water is held to the earth by the earth's gravity, but the slight impact the presence of these celestial bodies has on the gravitational force at the earth's surface creates two small tidal bulges of water following the moon around the sky. Since the earth rotates faster than the moon, the effect of friction from the earth's surface keeps these bulges slightly ahead of the moon's position. This has the effect of pulling the moon forward just slightly sending it into a higher orbit and robbing the earth of a small amount of its angular momentum.

The earth has a gravitational impact upon the moon as well, enough to slightly distort its distribution of mass as it rotates. This is the reason the moon has become “tidally locked” with the earth, always showing the same side to those on the earth's surface.

The earth has quite a bit of energy stored in its rotation, a total of roughly 2.1*10^29 Joules, or enough to supply the world's energy at today's rate of demand for a little over 400 million years. We cannot simply take this angular momentum from our planet at our will however, it depends entirely on the changes in water distribution caused by our moon.

The equation for energy in water works very similarly to our equation for hydroelectric power. If the tides raise the height of water by two meters over a square kilometer area (1,000,000 square meters) then this water with a density of 1000 kg per cubic meter will have a mass of 2*10^9 kg (2 million tonnes). Not all of this water will have two meters it is able to descend however. Only the water at the very top of our column will be able to return a full two meters down, the water in the middle will only be able to descend a single meter and the water at the bottom of the column will have remained at the original sea level. The average distance the water will be descending will be only a single meter. Thus, a 2 meter tide over a square kilometer region has 9.8 (gravity) *2*10^9 or 19.6 billion Joules of energy. There are roughly 700 tides per year so this would mean 1.4*10^13 Joules of energy per year in our hypothetical square kilometer.

Tides in the open ocean are fairly small and much harder to harness. The potential for harnessing tidal power exists mostly in bays and estuaries with large tides. No worldwide estimate exists for the total amount of tidal energy that can be reasonably harnessed; however, estimates have been made for bays and estuaries with at least one bank in England, which has a relatively large coastline and fairly high tides. England is estimated to have roughly 1.8*10^17 Joules per year of useable tidal energy. This represents less than 0.04% of the world's present energy supply. Even if we did scale this up to all of earth's useable bays and estuaries it would be difficult to imagine more than a couple percent of our demand being met by tidal power.

Costs

The United States department of energy has put together a report estimating the costs of most of the energy sources we discuss for the year 2016.


The overall cost is listed in the far right column, one megawatt-hour being equal to 3.6*10^9 Joules.

Most of the energy sources are able to compete fairly closely in terms of price with three exceptions: offshore wind, solar photovoltaics, and solar thermal. The main trouble is that offshore wind and solar were the two energy sources we investigated that actually had the potential to replace our current major energy sources, or even come reasonably close. The good news is that we have yet to look at the two energy sources we ignored at the beginning, biomass and nuclear energy. These two energy sources have the most potential to replace our current energy supply, but are also the most controversial for their perceived risk. Because of this, each of these energy sources will get the attention they deserve in their own future post.

Biomass
Nuclear

Note: If you have trouble verifying any of the numbers in this post feel free to ask in the comments for additional clarification. Most of the calculations are simply changing units to maintain consistency, but occasionally some additional steps were done.

Monday, October 25, 2010

Are Humans Omnivores?

You have probably seen some example of the multitude of posts around the internet arguing that it cannot be natural for humans to eat meat because we lack some characteristics possessed by all other meat eaters. This is a pretty weak form of argument, as can be made clear by this example:

Plants: Manufacture fructose
Animals: Do not manufacture fructose
Humans: Manufacture fructose

Plants: Are able to gather energy from the sun
Animals: Cannot gather energy from the sun
Humans: Are able to gather energy from the sun

There are two fallacies being used in this logic. The first fallacy is that of cherry picking. I have chosen only the data which confirms my conclusion that humans are plants. I have also cherry picked my definition of animals to include only the animals fitting the stereotypes I have defined. The second fallacy is guilt by association (which is itself an example of the fallacy of the undistributed middle). We have argued that all plants have some characteristic and all humans have the same characteristic and then tried to conclude from that fact that all humans are plants (although if we had a true dichotomy between being either animal or plant then actually showing that humans were not animals would be sufficient evidence to show that we were plants).

We can do better than simply pointing out that the logic behind this argument is flawed however, we can in most cases even explain why humans as traditional omnivores do not possess all these characteristics often possessed by other meat-eating species.

I have taken this post as a good example of the argument we are discussing.

Facial Muscles

CARNIVORE: Reduced to allow wide mouth gape
HERBIVORE: Well-developed
OMNIVORE: Reduced
HUMAN: Well-developed

Why are reduced facial muscles necessary for most meat eaters? The post even explains in the case of carnivores that it is in order to allow for a wide mouth gape. Some carnivores and omnivores hunt using their mouths as an important instrument in the kill. Humans do not use this method. We have historically used our hands in combination with tools in order to hunt and thus have never needed a wide mouth gape in order to hunt. This same explanation applies to why we have a seemingly herbivorous jaw type, jaw joint location, jaw motion, major jaw muscles, mouth opening versus head size, teeth of all types. There are still carnivorous and omnivorous species which do not hunt large prey with their mouths. Pigs are omnivores, eating leaves, grasses, roots, flowers, as well as insects and dead carcasses in the wild. Since their hunting style doesn't require them to kill large animals with their mouths they have facial structures very similar to our own in all of these areas.

Stomach Capacity

CARNIVORE: 60% to 70% of total volume of digestive tract
HERBIVORE: Less than 30% of total volume of digestive tract
OMNIVORE: 60% to 70% of total volume of digestive tract
HUMAN: 21% to 27% of total volume of digestive tract

Once again this applies to carnivorous and omnivorous species that hunt large prey. These animals often go for long periods between meals and then will consume a single large meal to survive on for long periods at a time. Most herbivores tend to graze throughout the day, not needing to hold a single large meal in their stomachs at once. Humans as animals that have evolved in small tribal settings have been able to share the meat of large kills with members of their community and have otherwise continued to typically eat several small meals throughout the day.

Colon

CARNIVORE: Simple, short and smooth
HERBIVORE: Long, complex; may be sacculated
OMNIVORE: Simple, short and smooth
HUMAN: Long, sacculated

Humans are along with all other primates in having sacculated colons. Ruminants are another group that tends to have sacculated colons. Sacculation of the colon in simple terms simply refers to the structure of tucks and pouches we find in our colon. In humans and primates this is thought to be a special adaptation to fermentation, allowing us to extract more energy from fiber.Source This adaptation would not be useful for carnivores who don't consume any significant amount of fiber. For other omnivores and many other herbivores they have likely all struck upon different solutions for improving digestion of fiber which doesn't require sacculation of the colon, much as many animals have evolved unique solutions to solving the problem of seeing.

Kidney

CARNIVORE: Extremely concentrated urine
HERBIVORE: Moderately concentrated urine
OMNIVORE: Extremely concentrated urine
HUMAN: Moderately concentrated urine

Animals with unconcentrated urine risk wasting too much water in order to excrete wastes through their urine. Animals with concentrated urine put themselves at higher risk of developing kidney stones and other kidney issues. Being a carnivore or herbivore has very little to do with striking this balance, while the prevalence of water plays a much larger role.

Nails

CARNIVORE: Sharp claws
HERBIVORE: Flattened nails or blunt hooves
OMNIVORE: Sharp claws
HUMAN: Flattened nails

Similar to facial structures, having sharp claws is only necessary if an animal is going to use these for hunting. Humans have never hunted using our nails and thus evolving sharp claws would be entirely unnecessary and quite a burden in our social lives. Once again omnivores like pigs or carnivores like anteaters do not have the features associated with their respective groups here.

Length of Small Intestine

CARNIVORE: 3 to 6 times body length
HERBIVORE: 10 to more than 12 times body length
OMNIVORE: 4 to 6 times body length
HUMAN: 10 to 11 times body length

This is not an accurate measure for omnivorous pigs whose, “small intestines have an average length of 15 to 20 m”Source. For those of you who aren't entirely familiar with the metric system a pig has a body length a little over one meter.

Why is this Important?

Anyone who is skeptical of veganism would see through this argument in a second. This is teeing them up to dismiss our arguments in an instant. Even more importantly however, we don't need this argument. Our recent ancestors have not been vegan, but the ethical reasons for being vegan still hold all the same. A well-planned vegan diet is still healthy during all stages of the life cycle. We don't need to use misleading claims to try to deceive omnivores when we have the truth on our side.

Sunday, October 24, 2010

Veganism by Religion

How does veganism vary by religion? To actually answer that question we would need to go around to a large sample of people from various different religions until we have found enough vegans to achieve some level of statistical significance, and I by no means have the time to take on that sort of experiment. The internet however does give us a useful tool for measuring how often the phrase vegan appears in the context of certain religious key words.

For a number of the world's major religions I measured the number of hits a Google search returned for a key phrase both preceding and following the name a member of that religion would most likely call themselves. For example I measured the number of hits for “Vegan Christian” as well as “Christian Vegan” and added these numbers together. I used quotations around all of my search queries to make sure the key phrase was being used in the proper context of the religion. I also measured the number of hits for simply the religion along and recorded this as well.

Once I had recorded data for all of my key phrases I divided the total number of hits for each keyword by the number of hits for the religion alone and took the natural logarithm of this result. For example, if “Vegan Christian” returned 8000 results, “Christian Vegan” returned 3000 results, and “Christian” returned 100000000 results I would have calculated ln[(8000+3000)/100000000]. I then took the average result from this calculation between all the key phrases and subtracted that from each cell to center the values around zero. Here is a graph of my results (Click to enlarge):



One thing you might notice about this graph is that the religion “Protestant” sticks out like a sore thumb. After a bit more research I decided this was because most usage of the word “Protestant” is for events like the Protestant Reformation, while actual Protestants themselves are more likely to identify themselves as being Lutheran, Methodist, Mormon, etc. The same does not hold for their cousins the Catholics or any of the other religions given. I then replotted the results with Protestants excluded:



The phrase vegan appears around “atheist” at roughly ten times the rate at which it is found around a more common religion like “Christian”. “Atheist” also was found at the highest rate around the key phrases “vegetarian” and “animal rights” as well. Somewhat surprisingly, atheists felt the need to proclaim themselves as “meat-eating” at above the average rate as well, but not nearly to the extent they proclaimed themselves vegan or vegetarian.

Contrary to this blog, the phrase “animal rights” was nearly never mentioned with the term “skeptic” (I am aware that skeptic is not a religion, but I threw it in there out of my own interest). I suspect the reason for this is that skeptics tend to shy away from discussing ethical or philosophical questions and prefer to stick to much more easily testable hypotheses. Interestingly, while “diet” saw very little variation between different religions, it was mentioned quite regularly by skeptics in comparison, likely in response to the great deal of dietary misinformation that gets spread around the internet.

Another piece that stuck out was the rarity with with the phrase “meat-eating” was used with being “Jewish”. I suspect this is because those who identify with these two terms are more likely to call themselves meat-eating Jews as opposed to admitting their interest in “Jewish meat-eating”. Other phrases such as “Jewish vegan” and “Jewish vegetarian” still held up fine however.

Muslims seem to be the group with the worst record around animal issues, scoring last for both “vegan” and “vegetarian” and relatively high around the phrase “meat-eating”.

I would be weary attempting to draw any conclusions from this data other than pure rate at which key words appear together. As you can see, a great deal of the variation has to do with each key word's usage in language. Nonetheless, as a preliminary look into the subject I found the results quite interesting.

For all who are interested, here is a link to my raw data.

Why Vegan?

Answering questions regarding why we ought to care about anything can be quite difficult. From the perspective of our universe as a whole the intentions of a few self aware lumps of water and carbon, inhabiting a single pale blue dot, orbiting one of hundreds of billions of stars, in just one of billions more galaxies, couldn't be more trivial. However, to us, the inhabitants of that pale blue dot, those intentions determine our very existence.

A great deal can be gleaned about why we act the way we do from evolution by natural selection. In a large portion of social encounters in which we can expect a large number of future interactions with another individual, the strategy that will yield the best expected outcome for ourselves is a tit-for-tat strategy, which means we act generously in our first encounter with the individual and then in all future encounters act toward them the same way they acted toward us in our previous encounter. Members of past populations who happened to possess genes predisposing them to using this strategy were more likely to pass on their genes to future generations.

While evolution can do an excellent job of explaining why we act in the ways we do, it has nothing to say about the way we ought to act. On some occasions our own interests will come at odds with what is most likely to propagate our genes. Maxing another character in WoW is unlikely to improve your chances of reproduction, yet people continue to attempt this task by the millions.

Many people choose to act in whatever way they feel is most in their own self-interest. Often times self-interest will still include some cooperation, but the ultimate goal is still the most personal benefit. As an individual making a personal decision for oneself, this decision is quite understandable, but as a conclusion on how we ought to act, it seems to place an unjustifiably high importance on solipsism. For each of us, our own interests are what is important. We also have every reason to believe that for everyone around us, their own interests are held in that same high regard. If we ignore the solipsism for a moment, the decision that would be of the most combined importance between all lumps of water and carbon would be to act in whatever way we could to maximize the fulfillment of interests.

Humans are by no means the only species with interests. If you have ever seen a baby pig squealing and writhing as its tail is being docked, you would say without doubt there is an animal expressing a strong interest. Similarly, the pig likely has a similar interest, that it is not yet aware of, in not suffering the medical consequences of leaving the tail undocked in factory farming conditions.

If we are to live up to our goal of acting to maximize the fulfillment of interests, then this cannot include only the human species. In the case of non-human animals our efforts can often go much farther than they would with humans. For less than a cent donated, Vegan Outreach estimates they are able to save a life. Compare that with the roughly $100 it would cost to save a human life in some of the poorest countries. This is still a tiny amount when compared to the tens or even hundreds of thousands of dollars many people expect in medical care in first world countries.

Many humans still suffer a great deal of pain which could be treated, but in comparison to the lifetimes of confinement and often torturous cruelty most non-human animals endure in today's factory farming conditions, this human suffering is a walk in the park. When combined with the relative simplicity of merely changing our diet, veganism clearly becomes an ethical imperative.

If you have not yet read the Why Skeptic question to our blog, I recommend doing that now as well.

Friday, October 22, 2010

Friday Fallacy - If I could Kill it Myself

This week's Friday Fallacy post is going to be an example of an ignoratio elenchi or irrelevant conclusion fallacy. Ignoratio elenchi can be used to describe a broad group of logical fallacies all of which possess the characteristic that the conclusion of the logic does not address the issue in question. This specific example of an ignoratio elenchi argument is the argument that whether or not we should be able to eat meat should be determined by our ability to kill the animals ourselves. I have chosen to call this week's fallacy “If I could kill it myself”; although, a more appropriate name for the general fallacy might be “Appeal to personal ability”.

One omnivorous blogger writes:
“I have started to realize (partially due to moving back to Alaska recently) that if I can't look an animal in the face, kill it and butcher it...should I be eating meat at all?
If I can't do it myself, I expose myself as a hypocrite, because I would rather have someone else do the 'yucky stuff' and I get to reap the benefits.”

A second omnivorous blogger seems to have put themselves through quite a bit of trauma trying to kill an animal in order to prove a point.
“I’ve spent a lot of words in recent posts explaining why I need to know where the animals come from that I eat, but standing there in the brutal sun, feeling like the earth was tilting under my feet and hearing a strange roar in my ears I questioned why this was so important. I felt quite as if I may pass out or possibly throw up at any moment, so why subject myself to this? I wish I could explain eloquently but I can’t. I only knew that if I’m going to eat meat, this was something I had to do. If animals can lose their lives for my dinner, I just needed to feel that I paid my own price, that of feeling the pain of taking one’s life.”

This is not a thought process unique to omnivores trying to justify their own actions as this vegan commenter makes clear:
“One big reason I quit eating meat in the first place was because I realized that I myself could never go out and kill another living thing, so why would I be okay with eating something someone else has bludgeoned to death?”

While our ability to kill an animal may speak to our personal squeamishness and, in the second example given above, personal resolve, it says nothing about whether the action is one we ought to do. If the simple fact that people had the ability to do things justified doing them, then we would have no grounds upon which to call any action unethical. Clearly (Modus Tollendo Tollens) our disagreement with this conclusion speaks to the fact that we do not hold this logic to be sound.

Thursday, October 21, 2010

Getting Ahead in Online Dating

I wrote a post a few weeks ago on how to convert non-vegan partners to veganism, which received a fair amount of criticism for being less than romantic on the subject. I hope to make up for that by providing a few useful tips toward finding your ideal vegan partner (or partner of any sort) on an online dating site. Not all online dating sites are created equal, and the differences go well beyond what you can find just browsing their homepages. They differ greatly in the number, gender, and education level of the people you can find there.

The first thing I looked at was the gender breakdown on these sites. I got all of the information being presented not from browsing the sites themselves, but rather by using Google's AdPlanner feature and recording the traffic statistics they supply. The gender breakdown is probably most important to people seeking a partner of the opposite sex as it plays a big role in how much you will stand out amongst the other people a potential partner may be searching on these websites. Here were my results (Click to see full size):



Ignoring the male specific website GayRomeo.com for the moment, the free online dating service OKCupid.com had the largest proportion of males to females with 64% of visitors to their website being recorded as male. On the flip side, the website Zoosk.com had the largest female to male ratio with 59% of visitors being recorded as female.

More shocking than the gender split between the websites was the diversity in educational level of visitors to the sites. I recorded the percentage of users who had received a bachelor's degree or above as a good measure of educational level, and surprisingly the results varied by as much as a factor of 5.



The two best educated dating sites also happened to be the male-heavy ones with OKCupid.com coming in at 37% of visitors having a bachelor's degree or above and GayRomeo.com coming in with 34%. On the flip side, there were quite a few services with absolutely abysmal education numbers. Mate1.com had only 9% of its visitors recorded as having a bachelor's degree or above, while True.com was recorded with a mere 7%.

The final piece of information I gathered was the sheer number of unique visitors coming to each website every day. If you are looking for a very specific sort of someone, then your chances of being able to find that sort of person are much better if you have a lot more people to choose out of.



Match.com seems to be far and away the most used online dating service with PlentyOfFish.com still living up to its name.

Taking all of these factors into account I'd recommend OKCupid.com as the best option for adrophiliac (meaning attracted to adult men) users with GayRomeo.com being a close second for male androphiliacs. For gynephiliacs (meaning persons attracted to adult females) I would suggest Match.com as the best option if you are willing to pay for a dating service, and PlentyOfFish.com as the best option for a free dating service. For female gynephiliacs looking for a well-educated crowd, OKCupid.com would also make an excellent option despite the somewhat smaller population.

Is Veganism a Personal Choice?

Many people accuse vegans of being too pushy on the grounds that veganism is merely a personal choice. They are using that phrase “personal choice” not in the sense that it is a decision we have made of our own accord (as opposed to when you take off your tin foil hat and the government places the decisions there for you), but rather in the sense that it is something which is acceptable for everyone to have their own unique opinion on.

What is it that makes something a personal choice in the latter sense? Some things we can agree clearly aren't personal choices. “I choose not to murder people, but if that's your cup of tea go right ahead.” or “Molesting children isn't for me. It is your own personal decision what you want to do in that arena though.” Clearly these examples are not going to fly. Some other things clearly are personal choices. “I don't buy orange carpet because I think it looks tacky.” I might advise someone against getting orange carpet, and might even pass some negative judgment against their decorating ability, but I would still fully recognize that they ought to be able to choose any color of carpet they like.

Some other things are not as clear. If someone wishes to eat a highly unhealthy diet putting their own health at risk, most of us would agree that is entirely up to them. If we then point out that the rest of society will then be expected to pay in the form of higher taxes and higher insurance rates to cover for this person's exceedingly high medical costs, suddenly their action becomes much less of a personal choice unless they are willing to cover the full cost of their actions themselves.

In the previous example, when the person's actions were only having a personal impact, we viewed it as a personal choice. When the impact extended to have significant implications for others it was no longer a personal choice. However, when the person once again offered to prevent the cost to others it became their personal choice once again. It appears that we judge something as a personal choice if the only individual who will suffer from it is the one who made the choice.

People who are vegan for animal rights reasons are doing so because of the impact our actions have on other animals. The entire animal rights argument is based upon a characteristic which clearly defines it as not being a personal choice. Accordingly it is unproductive to criticize animal rights based veganism as a personal choice without addressing the underlying animal rights message first.

Wednesday, October 20, 2010

Is Vivisection Good Science?

Vivisection, originally defined as surgery conducted for experimental purposes on living organisms is now commonly used to describe any form of testing on live non-human animals. Anti-vivisection groups often criticize vivisection in the latter definition on the grounds that it is both cruel and a poor means of gathering knowledge that can be applied to our own species.

There is no question that a great deal of cruelty is involved in current vivisection practices, but is there any basis to the poor science accusation? The National Anti-Vivisection Alliance writes:

“The prime reason as to why animal testing cannot be applied to humans is due to the difference in species, genetic make-up and vary in physiology and biology. We simply cannot get the results from one species and apply it to another. Beagle dogs, for example, cannot get heart disease due to being designed for a high intake of meat in their diet due to being solely carnivores, yet heart disease is rife in the human population. Lemon juice, something used commonly, can kill cats as do grapes to dogs.”

The site is certainly correct that we would be ill advised to draw many conclusions about heart disease by studying another species that does not get it, but does this mean there is no knowledge to be garnered by using other species as models?

In the case of diet, other animals tend to make fairly poor models for humans since we have all evolved along different evolutionary paths to fill differing dietary niches. For many other things we might study this is not the case. Many other animals break down alcohol very similarly to the way we do. Why should we not be able to model the breakdown of alcohol in these animals? Many other animals have skin that bruises or burns and bones that break under similar conditions to our own. Why should we not be able to model the effects of trauma and injury on humans in these animals? Many other animals possess a very similar structure in their brains as we possess in the core region of our own. Why should we not be able to learn something about a drug's effect on the core of our brain by studying its effect in these other animals.

The American Anti-Vivisection Society claims, “Nine out of ten drugs that appear promising in animal studies go on to fail in human clinical trials,” as a reason why vivisection cannot be useful. Yet if we look back at the example of using other animals' brains as models for the core of our brain, it will certainly be necessary after this trial to ensure that a drug has no effect on other systems of our brain and that it doesn't have negative consequences on other areas of our body. We haven't learned this from the animal tests, but we still may have gathered valuable information about the way a drug operates in the area of our primary concern.

While many of the experiments currently being conducted we might not see as having any practical and applicable purpose, Carl Sagan makes the point incredibly clear in The Demon Haunted World why we must be careful when criticizing any striving for new knowledge as being without practical value:


Giving money to someone like Maxwell might have seemed like the most absurd encouragement of mere “curiosity-driven” science, and an imprudent judgment for practical legislators. Why grant money now, so nerdish scientists talking incomprehensible gibberish can indulge their hobbies, when there are urgent unmet national needs? From this point of view it's easy to understand the contention that science is just another lobby, another pressure group anxious to keep the grant money rolling in so the scientists don't ever have to do a hard day's work or meet a payroll.

Maxwell wasn't thinking of radio, radar, and television when he first scratched out the fundamental equations of electromagnetism; Newton wasn't dreaming of space flight or communication satellites when he first understood the motion of the moon; Roentgen wasn't contemplating medical diagnosis when he investigated a penetrating radiation so mysterious he called it “X-rays”; Curie wasn't thinking of cancer therapy when she painstakingly extracted minute amounts of radium from tons of pitchblende; Rowland and Molina weren't planning to implicate CFCs in ozone depletion when they began studying the role of halogens in stratospheric photochemistry.

Members of congress and other political leaders have from time to time found it irresistible to poke fun at seemingly obscure scientific research proposals that the government is asked to fund. Even as bright a senator as William Proxmire, a Harvard graduate, was given to making episodic “Golden Fleece” awards – many commemorating ostensibly useless scientific projects – including SETI. I imagine the same spirit in previous governments – a Mr. Fleming wishes to study bugs in smelly cheese; a Polish woman wishes to sift through tons of Central African ore to find minute quantities of a substance she says will glow in the dark; a Mr. Kepler wishes to hear the songs the planets sing.


We do not know the results that may come from our curious seeking of new knowledge. That said, this doesn't give researchers a blank check to use anyone or anything however they should please. Just imagine how much more we could learn with unrestricted testing on other humans! All the shortcomings and difficulties of tests in other species would be eliminated, yet for some reason modern society has nearly universally condemned the non-consensual medical experiments of Nazi Germany. Many of the animals we currently experiment on suffer much as we would in these experiments. We may require anesthesia, but by no means would we find this small token acceptable as we brutally violated humans in the same ways we do to other animals today. From an ethical perspective, our reckless testing on non-human animals is behind only our consumption of them for the greatest misdeeds of our day in terms of suffering caused.

The guidelines we place on animal testing ought to change to more resemble the ones we currently have in place protecting our fellow humans, but what effect would this have on science?

Prior to sending the first human into space, the United States had launched five different monkeys and a mouse into space between five individual missions. At the time we had little idea what effect the lack of gravity and radiation at high altitude might have on any travellers. Since these animals had all evolved with a similar dependence on gravity and ordinary radiation levels as we had, and we saw no evidence of systems in humans that should be uniquely sensitive to these conditions, these other animals made good sense as models for what might happen to a human in space. We found from these missions that the animals did survive and were able to continue to function in space with no obvious health consequences. What would the United States have done had we not been able to test on these animals? I suspect our first mission would have been to build an airplane similar to the current “Zero G” plane capable of flying in parabolic arcs for up to 30 seconds at a time simulating the weightlessness of space. Next we would have probably designed a mission to launch someone to an altitude where they could experience free fall for roughly 10 or 15 minutes. Finally once all of these had proved to be safe we would attempt a full earth orbit mission.

This would have required additional time and cost for all of the safety precautions we expect in human missions, but by no means would it have prohibited the space race. There may be other experiments that may not be as easy to replace, but we must also be careful not to underestimate our own combined ingenuity when presented with new problems to solve. A good ethical system should be able to weigh the potential harm caused to the subjects against the potential benefit for results. Today our system only begins to do that with human subjects, and comes nowhere close with non-human animals.

Sunday, October 17, 2010

The Great Pacific Garbage Patch

What is the Great Pacific Garbage Patch?

To quote from wikipedia, “The Great Pacific Garbage Patch, also described as the Pacific Trash Vortex, is a gyre of marine litter in the central North Pacific Ocean located roughly between 135° to 155°W and 35° to 42°N. The patch extends over a very wide area, with estimates ranging from an area the size of the state of Texas to one larger than the continental United States […] The Patch is characterized by exceptionally high concentrations of pelagic plastics, chemical sludge, and other debris that have been trapped by the currents of the North Pacific Gyre.”

Do an image search for the Great Pacific Garbage Patch and you will see results like these:







Yes, it is not necessary to dig any further than the second Google Images result to find an image with a city clearly visible in the background, and the fifth result is apparently of someone who felt the need to canoe themselves all the way out to the center of the Pacific Ocean. Viewing the contexts in which these images appear, all of them seem to imply that these are images of the actual Great Pacific Garbage Patch, despite the clear impossibility of them being such.

One group of young environmentalists concerned about the Great Pacific Garbage Patch took a trip out to the center of the North Pacific Gyre in the summer of 2007 and filmed the entire ordeal. Take a look at 1:45-5:40 of this clip to get an idea of what they found.



These young environmentalists said numerous times that they had expected to find a large floating island of garbage as far as the eye could see. What they did find was that after an hour of trawling with a very fine meshed net, they were able to fill a jar with a murky liquid of plastic. Nonetheless, they justify that this is in fact worse than what they had expected. Why would this be?

Plastics do not hold together in direct sunlight. The combination of the constant jostling of salt water and the photodegradation caused by sunlight breaks nearly everything down to microscopic pieces well before it reaches the North Pacific Gyre. The microscopic pieces of plastic remaining in the water column are called neuston plastic. These bits of neuston plastic, along with any impurities they may have contained, can still be eaten by sea life and make their way into the food chain.

A couple of studies have tried to actually measure the amount of this neustonic plastic in the water. The first such study was done from 1985 to 1988. In this study, numerous areas across the entire northern Pacific were studied for the amount of plastic they contained by trawling a 500 micrometer (0.5mm) net behind a ship for 10 minutes at a time. This study found, “Total concentrations of neuston plastic generally were low, with high concentrations recorded at only four stations in Transitional Water, at two stations in nearshore water east of Japan, and at one station in Subarctic Water; total concentrations at the other stations with plastic generally were < 10% of the highest concentration (Fig. 2). The highest total concentration was 3,941.8 g/km2 at lat. 40"00'N, long. 171'30'E near the Subarctic Front in the central North Pacific.” This survey found no clear trend of higher levels in the area typically associated with the Great Pacific Garbage Patch; although, it provided no particularly strong evidence that it wasn't there either. Typical levels found, even in the central region typically associated with the garbage patch, were roughly 400 grams (approx. 1 pound) per square kilometer. Despite the unclear nature of their results, the authors do comment on how the distribution of plastic in the Pacific likely works:


“After entering the ocean, however, neuston plastic is redistributed by currents and winds. For example, plastic entering the ocean in Japan is moved eastward by the Subarctic Current (in Subarctic Water) and the Kuroshio (in Transitional Water, Kawai 1972; Favorite et al. 1976; Nagata et al. 1986). In this way, the plastic is transported from high-density areas to low-density areas. In addition to this eastward movement, Ekman stress from winds tends to move surface waters from the subarctic and the subtropics toward the Transitional Water mass as a whole (see Roden 1970: fig. 5). Because of the convergent nature of this Ekman flow, densities tend to be high in Transitional Water. In addition, the generally convergent nature of water in the North Pacific Central Gyre (Masuzawa 1972) should result in high densities there also.”



This prediction appears to be the origin of the hypothesis that a higher concentration of plastic exists at the center of the North Pacific Gyre.



More recently, in 2001 another group went to the center of the North Pacific Gyre to specifically measure levels of plastic there. They trawled the water with a finer mesh of net (333 micrometers instead of 500) and accordingly they recovered a higher density of plastic per square kilometer than the 1988 study. The nice thing about this study is that in 2002 the same group took the same mesh of nets and went to study the densities of neustonic plastic in the water off southern California. This study was able to make numerous comparisons between waters not considered part of the gyre and what is considered to be part of the garbage patch.

“The density of neustonic plastic along the southern California coast was about three times higher than Moore et al. (2001) found in the mid-Pacific gyre, though the mass was 17 times lower (Table 3). This disparity between density and mass reflects the dramatic difference in size of neustonic debris between the gyre and the coast. Most of the neustonic plastic mass observed in the North Pacific central gyre was large material associated with the fishing and shipping industries. Most of the plastic we observed near the coast were small fragments attributable to land-based runoff.

The average plastic:plankton mass ratio was less in southern California, reflecting its higher plankton density. However, the plastic:plankton ratio on the day after the storm was higher in southern California than in the North Pacific central gyre. This change resulted from an increase in debris following a storm, rather than from a reduction in plankton. Moreover, the ratio in the North Pacific central gyre was driven by large debris. When the comparison of ratios between these two areas is limited to debris smaller than 4.75 mm, which is the fraction that filter feeders are most likely to confuse with plankton, the southern California ratio becomes twice that of the North Pacific central gyre.”

Yes, contrary to what you may expect, there were more pieces, but less plastic mass off the coast of sothern California. The reason for this, as they explain, is because most of the plastic in the gyre was a few large pieces of fishing and shipping waste that they picked up. When we limit the findings to just the smaller pieces, there was far more of this plastic in southern California, and even twice the ratio of plastic to plankton even with the higher levels of plankton.

What should we conclude from this? The hypothesis that slightly higher levels of floating waste accumulates in the North Pacific Gyre certainly sounds like a reasonable one, but at this point I'm afraid we shouldn't treat it as much more than a hypothesis. Even if proves with future research to be true, changing winds, currents, waves, and storms still disperse the floating material enough to make the accumulation modest at best. The amount of small plastic waste we find in our near-costal waters will still be higher in nearly all areas.

There are certainly good reasons to avoid letting our waste leak into the oceans or other large bodies of water. At this point I have seen no research that has been done suggesting levels of any compound of plastic degradation is anywhere near unsafe levels in the North Pacific Gyre, but that doesn't mean such a study couldn't exist. Until I see the results of such research I am inclined to believe we have little more to fear from this area as we do from our oceans as a whole. Remain conscientious of the products you use, but the Great Pacific Garbage Patch is not the reason why you should do this.

Friday, October 15, 2010

Friday Fallacy – Illicit Minor

If you have not yet read last week's fallacy on the fallacy of the undistributed middle read that first, as this week's post will only make sense in light of that post.

Like the fallacy of the undistributed middle, illicit minor is also a syllogistic fallacy, and the form is fairly similar. The fallacy of the undistributed middle had the form:

All A are B;
All C are B;
Therefore, all C are A.

Illicit minor has the form:

All A are B;
All A are C;
Therefore, all C are B.

For example:

All animal rights activists are vegans;
All animal rights activists are humans;
Therefore, all humans are vegans.

As pleasant as this conclusion is, we clearly have yet to make it true. In a syllogism, the categorical proposition with the term that comes second in the conclusion, in this case, “all animal rights activists are humans,” is called the major premise, and the categorical proposition with the term that comes first in the conclusion, in this case, “all animal rights activists are vegans,” is called the minor premise. This syllogism is a fallacy because the minor term allows some humans to still not be animal rights activists, yet our conclusion tries to draw from the animal rights activist property of humans in order to draw its conclusion. The name illicit minor derives from the fact that the minor premise does not describe all of the individuals who are described as the subject in the conclusion.

It is still possible for syllogisms of this form to have true conclusions. One example might be:

All cats are animals
All cats are mammals
Therefore, all mammals are animals.

This conclusion is technically true, but it cannot be derived from the two premises given. The fact that the conclusion does not necessarily follow from the premises is what makes an argument a fallacy, not that it is necessarily false.

You may have noticed that last week's fallacy was a bit sparse on the examples. That is because most good examples of syllogistic fallacies are actually cases of illicit minor. Remember that things like “I am an animal rights activist” is the syllogistic equivalent of “All 'me' are animal rights activists.” Here are a few examples of illicit minor in action:

The book The China Study cites studies where animals fed diets high in casein developed certain cancers at a much higher rate than those fed other diets. Casein is an animal protein. We cannot conclude from this, as the China Study attempts to do, that all diets high in animal protein will lead to higher rates of those cancers.

Roundup ready crops may contain unsafe levels of pesticide residue. Roundup ready crops are genetically modified. We cannot conclude from this that all genetically modified crops are necessarily unsafe even if Roundup ready ones are.

All of my blog's readers are becoming more skeptical. All of my blog's readers are or are becoming vegan. Sadly, this doesn't mean that all people who are or are becoming vegan are also becoming more skeptical.

Keep fighting the good fight for rights and reason everyone! More fallacies are on their way.

Tuesday, October 12, 2010

Soy Dangers - Phytate/ Phytic Acid

It is time to look at another common rumor regarding soy foods; the dangers posed by phytates. Phytate is the name for the salt form of phytic acid, a phosphorus containing molecule in many plant tissues.

The Weston A. Price Foundation writes, “High levels of phytic acid in soy reduce assimilation of calcium, magnesium, copper, iron and zinc. Phytic acid in soy is not neutralized by ordinary preparation methods such as soaking, sprouting and long, slow cooking. High phytate diets have caused growth problems in children.”

The “natural health” website Mercola writes, “Soy contains phytates. Phytates (phytic acid) bind to metal ions, preventing the absorption of certain minerals, including calcium, magnesium, iron, and zinc -- all of which are co-factors for optimal biochemistry in your body. This is particularly problematic for vegetarians, because eating meat reduces the mineral-blocking effects of these phytates (so it is helpful—if you do eat soy—to also eat meat).”

Soy Online Service adds, “Soybeans contain very high levels of phytate and their[sic] are numerous reports of reduced bioavailablity[sic] of various metals from foods containing soy; this has particular significance for vegetarians and infants fed soy-formulas.”

We already learned from last year's post on The Dangers of Phytoestrogens that, “Comprehensive literature reviews and clinical studies of infants fed SBIFs[soy based infant formulas] have resolved questions or raise no clinical concerns with respect to nutritional adequacy, sexual development, neurobehavioral development, immune development, or thyroid disease. SBIFs provide complete nutrition that adequately supports normal infant growth and development.” Interestingly however, there is still quite a bit of truth to these concerns over phytate. Soy does contain phytate and phytate does reduce our absorption of several minerals.

There is one redeeming aspect to all of this however. Soy is not a particularly exceptional source of phytate. The 2001 book Food Phytates brought together a lot of information about phytates and published it in a very convenient fashion. Part of this book involved gathering data on quantity of phytate in various foods and arranging that into a convenient table. Here are a few bits of data from that table:

Source - %Phytate by mass
Dolique Beans – 5.92-9.15%
Brazil Nut – 1.97-6.34%
Almond – 1.35-3.22%
Tofu – 1.46-2.90%
Linseed – 2.15-2.78%
Pinto Beans – 0.61-2.38%
Soybeans – 1.00-2.22%
Peanuts – 1.05-1.76%
Kidney Beans – 0.89-1.57%
Tempe – 0.67-1.08%
Soy Milk – 0.05-0.11%

Do keep in mind that you probably consume much more soy milk by mass than you would soybeans or almonds. The book also mentions that, “Dry cereals account for 69.5% of the total global crop seeds/grains/fruit each year but synthesized 77.3% of the total PA [Phytic Acid]. Legumes account for 7.6% of the annual global production of crop seeds/grains/fruits and 13.0% of the total PA.” I encourage you to look through the entire table for yourself, which is available via Google Books.

The American Dietetic Association in their position paper regarding vegan and vegetarian diets brings up phytic acid or phytate several times, regarding calcium, zinc, and iron.

One recent study attempted to measure the absorption of calcium and zinc in Nigerian children with and without rickets. In the study the authors, “sought to examine 1) the effect of a typical Nigerian meal on the absorption of zinc and calcium 2), the effect of meal dephytinization on calcium and zinc absorption, and 3) whether the relationships between mineral absorption, meal consumption, and dephytinization were different in children with and without rickets.” Dephytinization is the word for removing phytate from a substance. The study authors went about this by giving the study participants a bowl of porridge along with a cup of orange juice fortified with both calcium and zinc to be consumed half way through. They repeated this process with both regular and phytate reduced porridges. While the study was largely about rickets, those findings had no detectable effect on the results. “Calcium absorption did not differ significantly between children with and without rickets for any permutation of meal.” Interestingly, they also note that the phytic acid had no significant impact on calcium absorption either. “Calcium absorption with fermented[phytate reduced] porridge (50.7 ± 19.1%) did not differ from unfermented porridge (50.1 ± 17.3%; P = 0.94).” The study also found rickets to have no detectable effect on zinc absorption. It did however find that dephytinization had a significant impact. “Enzymatic dephytinization increased zinc absorption during the second absorption study (55.5 ± 18.0% vs. 32.2 ± 14.8%; P < 0.001). Dephytinization resulted in a mean relative increase in zinc absorption of 101 ± 88%.” This study suggests that phytic acid has at most a modest impact on calcium absorption, but may affect the absorption of zinc fairly significantly.


The effect of phytic acid on iron absorption has been much more thoroughly studied. One study attempted to model iron absorption based off a number of factors and was able to achieve an r^2 value of .987 (usually interpreted as 98.7% of the variation in iron absorption rates could be accounted for by their model). The two main terms in their model were phytic acid content and ascorbic acid content (more commonly known as vitamin C). Their model found that the ratio of iron that was absorbed from an ordinary wheat roll increased linearly with the amount of ascorbic acid, decreased with the logarithm of phytic acid content. This means that as vitamin c increases the rate of iron absorption continues to increase at a similar rate, while as phytic acid increases it has a diminishing impact on the amount it inhibits absorption. Overall however, if you look at absorption from the vegetarian meals they studied the absorption of iron in those meals was still much lower than absorption from meat-containing meals. Perhaps this is why the American Dietetic Association suggests, “because of lower bioavailability of iron from a vegetarian diet, the recommended iron intakes for vegetarians are 1.8 times those of nonvegetarians.”

So while soy certainly isn't a guilty culprit, phytic acid absolutely has a negative impact on our absorption of minerals as vegetarians. What, however, is the net impact of all this on overall health? Perhaps a paper titled Health Effects of Vegan Diets in the American Journal of Clinical Nutrition can help answer this for us.

“[T]he risk of iron deficiency anemia are similar for vegans compared with omnivores and other vegetarians. Vegans often consume large amounts of vitamin C–rich foods that markedly improve the absorption of the nonheme iron.”

“Phytates, a common component of grains, seeds, and legumes, binds zinc and thereby decreases its bioavailability. However, a sensitive marker to measure zinc status in humans has not been well established, and the effects of marginal zinc intakes are poorly understood. Although vegans have lower zinc intake than omnivores, they do not differ from the nonvegetarians in functional immunocompetence as assessed by natural killer cell cytotoxic activity. It appears that there may be facilitators of zinc absorption and compensatory mechanisms to help vegetarians adapt to a lower intake of zinc.”

“More recent studies with postmenopausal Asian women showed spine or hip BMD was significantly lower in long-term vegans. Those Asian women, who were vegetarian for religious reasons, had low intakes of protein and calcium. […] The higher risk of bone fracture seen in vegans appears to be a consequence of a lower mean calcium intake. No difference was observed between the fracture rates of the vegans who consumed >525 mg calcium/d and the omnivore fracture rates.”

Overall it seems that our lower rates of absorption of zinc and iron are accounted for by higher intakes of those minerals. Getting enough calcium can be a concern for some vegans, but for those who do they seem to utilize it just fine. If there is one thing to take away from all this, I think the American Dietetic Association summarizes it best. “[A]ppropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases. Well-planned vegetarian diets are appropriate for individuals during all stages of the life cycle, including pregnancy, lactation, infancy, childhood, and adolescence, and for athletes.”

Plan your diet well, eat a healthy variety of foods, and no, eating soy is not going to kill you.

Saturday, October 9, 2010

Climategate – 1 Year Later

For those of you not familiar with the Climategate scandal, on the 17th of November, 2009 the servers for the Climate Research Unit at the University of East Anglia were hacked, leading to the leak of thousands of private e-mails and other documents to the public and eventually the press. In the days afterward, news outlets like Fox News would describe the e-mails as, “brazenly discussing the destruction and hiding of data that did not support global warming claims.”

The first statement from the University of East Anglia, where the researchers were employed and of which the Climate Research Unit (CRU) was a part, came a week after the e-mails were initially released. The University expressed at this time that they saw no reason for the resignation of professor Jones and that, if offered, they would not even accept his resignation. The University said it planned to conduct an independent review in order to address data security. Two weeks after the initial release of the e-mails the University announced that professor Jones would step aside from his post during the review, and a couple days later it indicated that a thorough investigation into the content of the e-mails would be included as well to determine whether there was suppression or manipulation of data.

The United Kingdom’s meteorological service, known as the Met office, works with the CRU in order to provide temperature data. The Met office initially stated that the incident was of no concern, but three weeks after the incident they agreed to reevaluate 160 years worth of temperature data and to make a large portion of this data available to the public.

The 2009 United Nations Climate Change Conference, commonly known as the Copenhagen Summit, was scheduled to begin on Dec. 7, 2009 in Copenhagen, Denmark, a mere three weeks after the initial hacking incident. The Copenhagen Summit was intended to serve as a follow up to the Kyoto protocol, and many had hoped that it would bring specific international agreements to cut emissions. 194 nations sent delegates to the Summit; however, in the midst of the public outcry created in the initial aftermath of the hacking incident, progress was difficult, and the incident may have played a large role in the lack of any binding climate change agreement at the Copenhagen Summit.

On January 22, 2010, the Science and Technology Select Committee of the House of Commons announced a review into whether requests made under the United Kingdom’s Freedom of Information Act had been handled properly. The committee invited written responses from all relevant parties and published 55 submissions it had received on the 10th of February including submissions from The University of East Anglia, The Met Office, the Royal Society of Chemistry, and the Institute of Physics. An oral evidence session was also held before the House of Commons on March 1st. On the 31st of March the Science and Technology Select Committee published its official report on the review announcing that:

“On the accusations relating to Professor Jones's refusal to share raw data and computer codes, we consider that his actions were in line with common practice in the climate science community. We have suggested that the community consider becoming more transparent by publishing raw data and detailed methodologies. On accusations relating to Freedom of Information, we consider that much of the responsibility should lie with UEA [University of East Anglia], not CRU.”

“In addition, insofar as we have been able to consider accusations of dishonesty—for example, Professor Jones's alleged attempt to "hide the decline"—we consider that there is no case to answer. Within our limited inquiry and the evidence we took, the scientific reputation of Professor Jones and CRU remains intact. We have found no reason in this unfortunate episode to challenge the scientific consensus as expressed by Professor Beddington, that ‘global warming is happening [and] that it is induced by human activity’.”

Perhaps in its greatest endorsement of the scientists’ reputations, the committee added that, “there is independent verification, through the use of other methodologies and other sources of data, of the results and conclusions of the Climate Research Unit at the University of East Anglia.”
Despite the harmless nature of the e-mail’s contents upon review, the media outcry surrounding the incident may have had a significant effect on the public’s opinion of climate change. Gallup polls taken in March of 2010 on global warming showed a sharp decline in public confidence and support from the previous poll in March 2009.



Figure 1: Polls of the American public show a significant increase in the number who think global warming is being exaggerated in the news, and a decrease in the number who think global warming has already begun or will begin in the next few years in the aftermath of the Climategate incident.

Science is not without its share of scandals. In science, as with all fields, there will always exist some temptation for individuals to try to get ahead, and sometimes through using methods other than the merit of their accomplishments. Scientific scandals, when discovered, often make large news in the media as can be witnessed in the case of cold fusion or the nanotechnology experiments of Jan Hendrik Schön. Carl Sagan commented on this in his book The Demon Haunted World: Science as a Candle in the Dark. “If you examine science in its everyday aspect, of course you find that scientists run the gamut of human emotion, personality, and character. But there’s one facet that is really striking to the outsider, and that is the gauntlet of criticism considered acceptable or even desirable.” Science could not function without this criticism given at every step of the way. “At the heart of science is an essential balance between two seemingly contradictory attitudes – an openness to new ideas, no matter how bizarre or counterintuitive, and the most ruthlessly skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense. The collective enterprise of creative thinking and skeptical thinking, working together, keeps the field on track.”

Scientists who are found guilty of falsifying data should absolutely face severe career consequences. Science, however, is not controlled by a single individual. Our knowledge of climate change is supported by a number of independent sources and is constantly being tested and retested worldwide. In science alternative hypotheses can always be presented and tested for their merits, experiments can be repeated, and experiments can yield data that is not congruent with the present theory. Sagan argues that our knowledge is benefited when our current hypotheses are put to the most rigorous tests. “General Relativity is certainly an inadequate description of Nature at the quantum level, but even if that were not the case, even if General Relativity were everywhere and forever valid, what better way of convincing ourselves of its validity than a concerted effort to discover its failings and limitations?”

The attacks on the researchers at the CRU were not attempts to retest their results, test alternate hypotheses, or find areas where their conclusions broke down and could be improved upon. The attacks on the CRU scientists were nothing more than ad hominem attacks attempting to challenge their science without doing the science that would call into question their results.

There is one area in which the researchers could be accused of not living up to the ideal of the scientific method, and that is in refusing to share all of their information with potential skeptics. As stated earlier, science thrives on and should encourage legitimate skepticism, and this means making available the tools and resources to make critiques of the methods being used and the conclusions being drawn. This need for transparency in research was also mentioned by the Science and Technology Select Committee’s report. “We recognise [sic] that some of the e-mails suggest a blunt refusal to share data, even unrestricted data, with others. We acknowledge that Professor Jones must have found it frustrating to handle requests for data that he knew—or perceived—were motivated by a desire simply to seek to undermine his work. But Professor Jones's failure to handle helpfully requests for data in a field as important and controversial as climate science was bound to be viewed with suspicion. He was obviously frustrated by other workers in the field trying to "undermine" his work, but his actions were inevitably counterproductive.”