The Food Chain
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Published byVexen Crabtree
2007.
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Published byLife on Earth began with thermophiliac organisms powered by heat from the Earth's core. Later, surface life evolved. It was powered by the energy from the sun, and then in layers of prey and predators. This page is a description of the energy transfer system known as the food chain and a look at some more esoteric issues surrounding the nature of this system, including discussions of genetically modified food.
Life started deep in the crust of the Earth, where the oxidation of sulphur was powered by the intense heat from below. These ancient thermophiles eventually multiplied, diversified and evolved to cope with colder and colder climates. When a chance mutation resulted in the production of light-sensitive chemicals, life eventually emerged on the surface and floated in the cooling oceans.1. Micro-organisms are still the most diverse and successful forms of life on the planet.
A spoonful of good quality soil may contain ten trillion bacteria representing 10 000 thousand different species! In total, the mass of micro-organisms on Earth could be as great as a hundred trillion tonnes - more than all the visible life put together.”"The Origin of Life" by Paul Davies (2003)1
Forgetting the ancient thermophiles, the Sun is the engine that has since kept surface life on Earth sustainable. Photosynthesis converts radiation from the sun into chemically stored energy, creating organic molecules in the process, and expiring oxygen into the atmosphere. The rate of plant growth is called 'production'. Production is measured in grams per meter squared per year. For example, shallow waters produce 2500g/m2/yr. By dividing living creatures into layers, we can examine how energy from the sun makes its way up the food chain in the form of biological chemicals. These 'layers' are called trophic levels:
“The fate of energy can be followed through a consideration of a simple energy transfer model, called a food chain. Each stage in the chain is called a trophic level. Plants are the first level in the chain and are called producers. [...] Herbivorous animals are the second trophic level and are called primary consumers. They in turn are eaten by the third trophic level. [...] At each trophic level a conversion to heat takes place, which means that less energy becomes biomass at the succeeding trophic level. [...] This explains why most food chains are limited to four or five trophic levels, and why the animals at the end of the food chain, for example lions, have to roam over large areas to obtain their food, because one small area cannot support many of them.”
"The Nature of the Environment" by Prof. Andrew Goudie (1993)2
Depending on how you count, bacteria makes up nearly 50% of the biomass of the whole Earth3. That's right - nearly half of all life is bacterial (and over half is microscopic1). This provides a massive first-layer, primary food source for slightly complex multicellular life forms. Consumption, like all mechanical engines and chemical pathways, is not 100% efficient. Far from it. At all stages, energy is lost to inefficiency, wasteful digestive systems, and heat production. Prof. Dawkins, the foremost evolutionary biologist, informs us that only ten percent of the energy from one trophic level makes it to the next level up4.
This implies that at most trophic levels, the total biomass must decrease, the feeding/hunting area must be bigger, and the digestive systems have probably evolved to be more complicated in order to digest more complicated fats and sugars. It turns out to be true. Bacteria feed over a very small area, plants and primary producers feed over a wider area but in total, less biomass is held in plants than in bacteria (that make up 50%), and eventually, the predatory animals hunt over wide areas, and are massively fewer in number than their prey.
Dr Richard Wrangham of Harvard University notes that cooking is a behaviour found universally in human societies. Only very few single individuals attempt to live without it. Some have theorized that this radical behaviour formed a major factor in our rise to stardom. Dr Wrangham investigated the effect it has on food, and finds that it hugely improves the efficiency of the energy gain from the food cycle. Commentary was published in The Economist:
“Cooking alters food in three important ways. It breaks starch molecules into more digestible fragments. It "denatures" protein molecules, so that their amino-acid chains unfold and digestive enzymes can attack them more easily. And heat physically softens food. That makes it easier to digest, so even though the stuff is no more calorific, the body uses fewer calories dealing with it. [...] Cooking increases the share of good digested in the stomach and small intestine [...] from 50% to 95%.”
The Economist (2009)5
The improved food-consumption efficiency that is gained through cooking, and the learning curve of dealing with fire, and tools, are three things that set humankind on a radical new evolutionary path.
Energy Efficiency (assuming alien life is a little similar to ours): Life on alien planets could also be dividable into trophic levels; that the greatest abundance of biological chemicals is contained within unicellular lifeforms is great pressure for hungry multicellular species to evolve in a direction that involves digesting single-cell lifeforms. The result is a trophic system. It is also likely that on other planets, as on Earth, the evolution of digestion isn't optimal. The jury-rigged nature of evolution does not mean that the most-efficient routes are always evolved. What works, may survive. In short, there is a maximum limit to the amount of trophic levels you can have. Humans, who shop for food over massive distances (the whole planet), exist at the top level alongside other big omnivores. The footprint of the top hunters is huge, and by and large it is too inefficient for hunters on the top layer to spend time hunting each other. If plankton only process 10% of the sun's energy efficiently, and millions are eaten by fish at only 10% efficiency, etc, it is more efficient for predator fish to eat the next layer down in order to 'collect' the same quantity of plankton-food-mass. To eat each other would result in no net gain of energy into that trophic layer; so, much energy must be obtained from the layers below. At each layer, the storing of fats and sugars gets more complicated. The more complicated the biological chemicals, the harder it is to digest them. That's why bacteria doesn't eat chocolate, but we can. At the top trophic layer, our digestive systems can break-down chocolate into the smaller chemicals prevalent in lower trophic layers, and digest it. We then reassemble it into complex proteins, etc. If aliens visited Earth, they would be unlikely to eat us because the digestive or processing time would be very large (if, of course, they could digest us at all).
Incompatibility (assuming alien life started-out its evolution with different chemicals in the atmosphere to what we had on Earth): Proteins, carbohydrates and sugars all 'make sense' to animal digestive systems because all life on Earth has evolved from common sources, in an environment rich in their constituent molecules. On an alien planet where advanced life has evolved, if the starting-point was different, the nature of life's building-blocks will be different. Duplicating molecules, the stuff that causes evolution, grows up to use the molecules that are available. The environment shapes the resultant structure of life. We cannot eat silicon-based chemicals, but we can digest carbon-based ones. If a hot planet produces aliens that eat silicon, they might find all life on Earth to be far too insubstantial, and all but inedible. Given the fussiness of what we can eat, and even the dangerous nature of eating food that is too far removed from our historical diets (i.e., fish, plants, small animals, etc), we could probably not eat life that didn't evolve on Earth, nor could they eat us.
But despite these formidable problems, there is another possibility. We know that life can evolve on planets where carbon and other CHOMSP chemicals are abundant and available. It might be that this particular combination is the only efficient way for life to evolve. Of all the planets, life might only evolve on those with the right mix of chemicals. These means that all life could be comprised of many similar chemicals to ours. Not only might there be aliens that can digest us... but all aliens might all be able to digest each other, including us! Although this means that universal cuisine is going to be much more fascinating than planet-by-planet dishes, it also means we haven't quite finished our examination of whether aliens will eat us.
Sometimes, Humans eat each other. We tend to be a food-orientated species. Meals, cooking, meats, sauces, all kinds of plant life and fish, are palatable to us. It might be that we see no reason why we can't eat aliens. Some of us, I dare say, would strive to do so. Some aliens might be similar to some Humans: They would love to find out what an alien tastes like! And, legal or illegal, moral or immoral, they might proceed to do so! What if, then, the first aliens that discover Earth are a species, or even just a group of rogues, who are searching in particular for things to eat? And what if life in the universe is largely carbon-based, and we're edible? Perhaps we would engage in some prisoner exchanges, where instead of cremating criminals who have been executed, we part-exchange them for alien meat!
But, rogues aside, I think it more likely that the more organized alien species are the ones likely to find us, and also these species are less likely to have rogue spaceships wondering around. The foremost evolutionary biologist, Prof. Richard Dawkins, points out (2006) that as species-bias decreases in advanced species, we will seek more and more to avoid harming all other animals. This process is of course evident in Earth history. Alien neurology will lead them to understand that animals and foreign species have feelings like theirs, and will eventually evolve culturally to a point where they seek to avoid pain and harm to others. As a result, the chances are alien governments will not try to eat us. Observe the way that the most advanced countries are the least barbaric, and have the most processed, unnatural foods. If this continues, we will stop eating anything that comes from living material. If aliens continue to evolve technologically, they will likely arrive at the same point. Space travel, especially, requires long-term sustenance on non-living food. Advanced space travellers will probably not eat us, after all, and their governments will probably reign-in any rogue aliens that do try to, just like Human societies monitor their own cannibals and bloodsports practitioners.
So in summary: It is unlikely that aliens would be able to obtain enough energy from us efficiently in order to need to eat us. In addition, if life evolves under various conditions in the universe, aliens will probably have a biochemical make-up so different from ours that we are mutually inedible and potentially very poisonous to each other. But, if life all over the universe is carbon-based and can not evolve elsewise, we might find aliens can digest us (or us them). However, as advanced society relies less on living food and increasingly processes its food, and continue towards non-violence and non-harm towards an increasing range of animals (apes, baboons, Yorkshiremen, etc), and space-travel is (probably) only possible if you can survive on such processed food, it is very likely that space-faring aliens will not be seeking to eat us. Especially as advanced species probably watch out for transgressions amongst themselves, just like advanced moral countries prevent animal cruelty and bloodsports. In short, if we find aliens they probably can't eat us, and wouldn't.
Now, enough about aliens, and back on to purely Earthly and Human concerns, although concerns that are of no less a spurious and otherworldly nature.
Many single-cell lifeforms survive off of sunlight, water, and transient chemicals found in the oceans. These simple lifeforms are a Buddhism" JQPU_Content="The belief that meditation and good living can break the cycle of reincarnation and result in enlightenment
About Buddhism" class="www.humanreligions.info/buddhism.html">Buddhist ideal: They harm no other creatures and feed on nothing living. In a perfect world, all life would have evolved to survive in such a way. With modern technology, we can produce energy to make digestion mostly unnecessary if only we'd have evolved in a way that didn't evolve eating-other-life. All animal life has evolved in a way that makes killing other things necessary. I think that not a single multi-cellular species on Earth survives without directly harming other living life. The Buddhism" JQPU_Content="The belief that meditation and good living can break the cycle of reincarnation and result in enlightenment
About Buddhism" class="www.humanreligions.info/buddhism.html">Buddhist author Ken Jones describes this as 'ecological violence' and states that it is problematic for Buddhism" JQPU_Content="The belief that meditation and good living can break the cycle of reincarnation and result in enlightenment
About Buddhism" class="www.humanreligions.info/buddhism.html">Buddhists, who do not want to harm any living thing, that life itself requires violence:
“Ecological 'violence' can equally be seen as ecological 'harmony' and balance. One animal supports the life of another by becoming its prey. 'Violence' harmoniously sustains the life-affirming food chain. Humankind, [...] was part of this harmonious balance of violence-and-peacefulness. [...] Taizan Maezumi, a contemporary Zen Master has observed that if we think of the Buddhist First Precept 'on a common sense level of "Do not kill" or "Do not take any form of life", how could we survive? [...] Survival of life itself depends on killing other forms of life. [...] 'Violence' and 'harmony' [...]. When each disappears, what is there then?”
"The Social Face of Buddhism" by Ken Jones (1989)6
The author then states that Buddha-nature in us is the cure to this inherent problem, that ethical enlightenment and a Middle Way solves the problem of Human nature. However... all religions think that they have the answer to the problems of Human evil. In the case of Buddhism" JQPU_Content="The belief that meditation and good living can break the cycle of reincarnation and result in enlightenment
About Buddhism" class="www.humanreligions.info/buddhism.html">Buddhism, it could be said that its solution is exactly the same as common-sense would dictate: Intelligence, moral thinking and societal training are the solutions to redirect out-of-date and antisocial instincts. The best intentions, however, do not change the fact that it is not just Humans that hunt and kill for food and fun, but animals too. Ecological violence is a fundamental part of the cycle of life. All life dies, and all life requires the death of others, in order to live. This 'victory of death' is hailed by Satanists as a supreme sign that if there is a God, it is an evil one:
“The main piece of evidence here is biological matter and the food chain. All life dies - all biological life decays, erodes, fades, becomes diseased and ill if it does not sustain itself. To sustain itself nearly all life, except the least living elements of life, kills and eats other life. If not this, then it consumes biological matter at the expense of other living beings; the fight for food is also a case of living beings being required to outdo each other merely to survive.
If life was created, and not simply the result of undirected unconscious evolution (as seems sensible), this is surely the worst possible way to have created life. It appears very much that life cannot survive without causing suffering for other life. A god could not have created a more vicious cycle if it tried: Tying the very existence of life with the necessary killing of other life is the work of an evil genius, not of an all-powerful and all-loving god, that could choose if it wanted to sustain all life immediately and forever with manna from heaven. But it seems such an all-powerful good god doesn't exist.”
"God Must Be Evil (If It Exists): 1.2. The Dominance of Death in Nature" by Vexen Crabtree (2003)
[ + A Description of the Evolutionary Arms Race + ]
“Capsaicin, glucosinolates and hundreds of thousands of other chemical compounds produced by plants appear to be the products of millions of years of evolution in which plants have evolved deterrents and toxins against their natural enemies. [...] Every novel defence by a plant gives an advantage to any natural enemy able to evolve a means of overcoming that defence. Natural enemies with this advantage spread, and thus the enemy population evolves along with the plant population. This process is called coevolution and has been compared to an arms-race. [...] The evolutionary arms-race between plants and herbivores is a ceaseless one. Genetic variation is the raw material of evolution, and within populations it plays an important role in the evolution of defence.”
"Biodiversity and Ecosystems" by Silverton, Wood, Dodd & Ridge (2008)7
This desperate, deadly struggle for existence was agonized over by the father of evolutionary theory, Charles Darwin.
“I cannot see as plainly as others do, and as I should wish to do, evidence of design and beneficence on all sides of us. There seems too much misery in the world. I cannot persuade myself that a beneficent and omnipotent God would have designedly create the Ichneumonidae [wasps] with the express intention of their [larva] feeding within the living bodies of Caterpillars, or that a cat should play with mice.”
Charles Darwin (1860)8
It is clear that if the system of life was "designed" at all, it was by someone with no morals and not much foresight. Most biological organisms have to engage in violent actions to try and eat other living beings, creating a world of necessary evil and strife, all of which pre-dated mankind (therefore our own free will is not the cause of this endemic natural suffering). How ironic, then, to the point that it is not amusing, that in Genesis 6:13 [KJV]" JQPU_Content="About: Bereishit / Genesis
13 And God said unto Noah, The end of all flesh is come before me; for the earth is filled with violence through them; and, behold, I will destroy them with the earth." class="www.holybooks.info/genesis.html#Chapter6">Genesis 6:13 God justifies The Flood by saying that "the end of all flesh is come before me; for the earth is filled with violence through them; and, behold, I will destroy them with the earth". As you'd expect God, apparently being all-knowing, would have known that that was going to happen!
Links:
“Small animals feed on insects. Large animal predators feed on small predators. This is natural. This is normal. We are not surprised when, one level up, we find that we eat "lower" animals, such as rabbits. It's how it is. Our intelligence and development has made us the arbiter of life on this planet. We value Human lives much more than animal life. So, we side strongly with the survivors of zombie plagues and we feel they have every right to survive by killing zombies, because the living are so much better than them. Through several levels of the food chain, we are happy to admit that it is normal for the higher species to use lower species. But why, then, do we draw the line at our level? Vampires, and the elite, are a level better than the untermensch, so why are we appalled when "they" use us according to the natural laws that we accept? We accept natural laws to justify our using of lower species, so how come we find it so repugnant when higher species use us? The reason is that our justification for the food chain is fake; the real reason is necessity. We will do what it takes to keep on top. Likewise, so will vampires. And so will the human survivors of zombie films: They will kill, in order to keep in power.
Zombie and vampire films therefore, teach us much about humanity and the will to power. We learn that the 'natural laws' that we use to justify our existence at the top of the food chain are not the real justifications, and that we are simply self-interested, species-biased and paradigm-biased. Anything better than us we fight against, and anything weaker than us we exploit.”
"Zombies Verses Vampires: The Elite Verses the Masses: 2. The Right to Survive"
Vexen Crabtree (2006)
Prof. Richard Dawkins, a foremost biologist and expert in evolution, explains that Human culture has a history of species-ism:
“The feeling that members of one's own species deserve special moral consideration as compared with members of other species is old and deep. Killing people outside war is the most seriously regarded crime ordinarily committed. The only thing more strongly forbidden by our culture is eating people (even if they are already dead). We enjoy eating members of other species, however. [...] We cheerfully countenance the shooting without trial of fairly mild animal pests. Indeed we kill members of other harmless species as a means of recreation and amusement. A human foetus, with no more human feeling than an amoeba, enjoys a reverence and legal protection far in excess of those granted to an adult chimpanzee. [...] The foetus belongs to our own species, and is instantly accorded special privileges and rights because of it.”
"The Selfish Gene" by Prof. Richard Dawkins (1976)9
The Skeptical Inquirer magazine is famous for its careful facts-only analyses. Their summary of the state of GM food in Europe reads:
“In Europe, only one genetically modified (GM) plant variety is cultivated: the insect-resistant Bt GM maize. Even so, its cultivation is still very controversial. [...] Opponents to the use of biotechnology in agriculture are still very aggressive, particularly in France. They seek to ban all GM food for humans and animals. Greenpeace and the well-known neoluddite José Bové are heavily lobbying both the French government and European commissioners. [...]
More than 500 scientists from French and European public research organisations [signed a declaration to] affirm that any new plant variety, genetically modified or not, should be considered only on a case-by-case basis. They note, and specialized committees throughout the world agree, that the insecticidal active compound present in Bt GM maize has been exploited for decades by conventional and organic gardeners without any observable toxic or allergic response. [...] These signatories state that the "No to GMO" campaign is based only on imaginary or false uncertainties.”
Skeptical Inquirer (2008)11
And around the world:
“25 countries now grow GM crops, with the total area under cultivation now larger than Peru. Three-quarters of the farmland used to grow soya is now sown with a genetically modified variant, and the figures for cotton are not far behind. [...] Such stories of success will strike fear into some hearts [...] but lacking supporting evidence they have never been compelling. On safety, the fear which cuts closest to home, the record continues to look good.”
The Economist (2010)12
A particularly forceful defence of the safe nature of GM food was given by Lord Tavern:
“As argued in other essays in this volume, there is no evidence that GM crops have ever damaged human health, while they have already shown substantial benefits to some of the world's poorest farmers and can potentially make a huge contribution to the reduction of poverty, hunger and disease. Over five million small farmers in China, India, South Africa and elsewhere now farm GM cotton. Not only has their income been substantially increased by savings from the reduced use of pesticides, but their health has also improved. These are actual, proven benefits.[...]
There is no reason to regard GM crops as less safe for human consumption than conventional crops: this is the opinion of [four] Royal Society reports, one report by seven international academies of sciences, as well as any number of reports by prestigious committees, including two by the Nuffield Council of Bioethics (a mixed committee of scientific experts and lay representatives). Nor has any evidence emerged that they will create new 'super-weeds' or that they are especially dangerous to biodiversity.”
Lord Tavern 'The Harm That Pressure Groups Can Do'
In "Panic Nation: Unpicking the Myths We're Told About Food and Health" by Feldman & Marks (2005)13
When?
“Meat grown in vats, rather than in the form of animals, could soon be on the menu. It might even be healthier and better for you. [...] Researchers believe it will soon be possible to grow cultured meat in quantities large enough to offer the meat industry an alternative source of supply.”
The Economist(2006)14 (the bold emphasis is mine)
"At least another decade of research is needed" before we can even begin to effectively confront the critical issues of scale and cost.
P. K. Thornton (2010)15
Winston Churchill in the 1920s predicted that cultured meat would be in use within 50 years.16
Meat in vats, grown in culture from a chemical source derived from animal genetics, will result in meat being grown more like plants than livestock. Such research aims to massively reduce the land and resources used by meat production, increase the safety and nutritional value of meat, stop animal suffering and prevent the further hunting of endangered species for food. It has even been researched by NASA in 2002, as part of an investigation into food production on long-haul space flights17. The Economist newspaper in 2006 hailed it as a future industry14. Animal farming as an industry is in distress in the modern world, and is criticized for its heavy use of water and for its inhumane nature. In 2012, the People for the Ethical Treatment of Animals was offering a $1 million prize "for progress in producing meat from cells"18. The potential benefits of growing synthetic meats in a sterile and controlled manner are huge.
There are public-relations problems with highly scientific and new endeavours such as this. The European Barometer poll in 200519 asked respondents across all 25 European countries (and a few prospectents), whether they approved of growing meat from cell cultures so that we do not have to slaughter farm animals. Over half disapproved (54%), and only 6% of EU citizens thought that such meat should be grown for general use. The popular press has never reported on the potential benefits of this type of natural-synthetic meat. Here they are:
Animal welfare:
No livestock needs to be kept in captivity, so, synthetic meat causes no animal suffering, requires no slaughter and no animal transportation.
Vegetarians who abstain from meat because of their revulsion of the treatment of animals, could eat synthetically grown meat20.
Rare and endangered animal meat can be produced without every risking further damage to population numbers.14, 16
The Natural Environment and diseases:
Calculations indicate that cultured meat grows could use up to 60% less energy for pork, sheep and beef (although artificial chicken would use more), and they would produce perhaps as little as one tenth of the greenhouse gasses, whilst using 98% less land. In contrast animal livestock eats up 40% of the planet's cereal grain, uses 70% of its arable land, and 8% of the world's water supply. They produce up to a quarter of the greenhouse gasses produced by human activity. Cattle alone dump 64 million tons of sewage into the United State's infrastructure.16
Livestock consume large quantities of antibiotics en masse, which contributes to the emergence of drug-resistant bacteria, especially over the long-term. Synthetic foods are grown in a sterile and controlled environment, where antibiotics are not necessary.
Animal diseases cause havoc to food production and even occasionally jump species to infect humans, as happened with the chicken flu. There is no such risk with synthetically grown meat.
Meat and animal products are the biggest source of disease in the food industries of the United States, Europe and Canada. Synthetic meat is grown in sterile and controlled conditions, "avoiding Salmonella, E. coli, Capylobacter and other nasties"14 and voiding the requirement for antibiotic chemicals, for which animal meat has to be periodically checked.
Production:
In 2000, 228 million tons of meat was consumed "and that number is expected to more than double by 2050 as world population swells to nine billion"16. The environmental impact of increasing our meat production in tandem with our general population growth means that solutions such as synthetic meat will become necessary, whether we like it or not!
Scale of production of synthetic meat can be altered in sync with demand, without having to worry about what to do with surplus living animals.
"We will be able to control not only its flavour but its nutritional composition as well"16 - nutrients can easily be added to the meat (i.e., more iron, more vitamins, omega-3 fatty acids, etc) and the meat's bad contents (fat, etc) can be closely controlled.
Commonly stated disadvantages are generally misguided:
It is unnatural: The meat is perfectly natural, produced from natural genes found in natural animals, which produce the same natural proteins that they'd create in live animals as well as in cell cultures. We already consume large quantities of unnatural foods such as processed meats and cheeses and foods that are completely altered by chemical actions and factory production.
It is dangerous, or, there are unknown risks. Scientists have been growing cell cultures from stem cells for a long time, and, the scientific tests done on this meat have far outstripped the amount of testing we've ever done on livestock meat. Grown synthetic-natural meat is, due to the lack of diseases and natural contaminants, safer than livestock meat. Also, the demonstrated risks of highly processed food (junk food) are quite high. "As Ingrid Newkirk of PETA, an animal-rights group, puts it, 'no one who considers what's in a meat hot dog could genuinely express any revulsion at eating a clean cloned meat product' "14. It makes no sense to continue to eat and drink risky foods (crisps, alcohol, fatty foods) that are known to cause ill health, while protesting against theoretical and unknown risks in healthy food.
Some genuine criticisms:
It will no doubt be an expensive alternative to animal meat for a while. Given the nutritional, health and safety advantages of synthetically grown meat, it will be criticised for being yet-another expensive food that allows developed countries to increase gap between themselves and the poor.
If synthetic meat becomes cheaper due to economies of scale and increased efficiency over time, it will be criticized for harming farming markets and pushing down the costs of food. However, given the requirements of increased food productivity whilst using less space and resource, there is little choice but to decrease traditional markets if possible.
Taken from "Evolution and the Unintelligent Design of Life: Inherited Traits, Genetic Dysfunction and Artificial Life" by Vexen Crabtree (2007).
I will now offer four arguments that genetic engineering is in accordance with God's will - and also offer one cheeky argument that at the very least, genetic engineering foils the Devil's plans! So for those of us who don't believe in such dualisms, take the following with a philosophical pinch of salt: