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Ten Animal Welfare Myths

by Tim Harding, B.Sc.

(An edited version of this essay was published in The Skeptic magazine, June 2014, Vol 34 No 2, under the title ‘Creature Features’. The essay is based on a talk presented to the Mordi Skeptics in February 2012).

The term ‘animal welfare’ is not easy to define, but it usually includes the mental and physical aspects of an animal’s well-being, as well as people’s subjective ethical preferences as to how animals should be treated.  These preferences can give rise to a range of opinions about animal welfare; but as we skeptics are fond of saying: ‘people are entitled to their own opinions but not their own facts’.

I realise that this article may be controversial, even amongst my fellow skeptics.  Nevertheless, I would like to focus on some common factual misunderstandings about animal welfare; and try to dispel a few myths.

There appear to be two extreme polarised positions in the community regarding animal welfare.  An outdated view, often attributed to Rene Descartes (1596 –1650 CE), is that animals are not consciously aware, and are therefore unable to experience pain and suffering.  At the opposite pole are those who believe that animals have rights like humans do; and that hunting, farming and other uses of animals for human purposes are morally unacceptable.  Between these two extremes are various other views, including evidence-based or scientific approaches versus the so-called ‘organic’ or free-range farming industries.

Animal welfare science is a relatively new field of study; but some good research is now being done – including in Australia.  The two main experimental approaches are firstly, animal physiological and biochemical testing (e.g. blood tests) to objectively measure stress in animals under different conditions; and secondly, animal behavioural and preference studies (such as testing whether animals prefer more food or better surroundings).

Myth #1: Animals are best treated like humans

The attribution of human characteristics to non-human animals is known as anthropomorphism.  It is sometimes used to appeal to human emotions in campaign slogans about animal welfare (e.g. ‘Meat is murder!’ and ‘How would YOU like to be kept in a cage?’).

There are two main problems with an anthropomorphic approach to animal welfare. Firstly, it is emotional rather than evidence- based – and is therefore unscientific or lacking in objectivity.  Secondly, treating animals like humans is often a projection of human preferences rather than a consideration of the real needs of the animal.  Apart from the obvious differences in intelligence, anatomy and physiology, animals have different instincts to humans and they express a much more limited range of emotions than humans do.

Most of us love our pets and regard them as members of the family.  But treating them like little humans may not actually be in their best interests.  For instance, most of us are aware that chocolate is poisonous to dogs, but we may not be as aware that onions, garlic, grapes, avocados and macadamia nuts are also toxic to canine animals.[1]  Many dogs are also lactose intolerant, so dairy products are not a good idea for them either.[2]  So we should be careful about feeding human leftovers to dogs.

Myth #2: Dogs are tame wolves

Our treatment of dogs has been shaped by a historical view that they are basically wolves with nicer table manners. This is the concept behind much of traditional dog training – that dogs are pack animals competing with humans for dominance over the family.  This outdated view is now being challenged by modern canine science.[3]

All dogs are different varieties of one species descended from wolves.  Archaeological evidence now shows that dogs were first domesticated over 20,000 years ago – long before the first human settlements (around 9000BCE) and while we were still hunter-gatherers.  Dogs used to follow human hunters and scavenge from our leftovers.  We may have even used dogs to assist in our hunting.

Over this quite long period, dogs have been selected by humans for their mental temperaments as much as their physical characteristics.  As a result, modern pet dog breeds often bond more closely with humans than with other dogs.  It can therefore be bad welfare to deprive pet dogs (not farm dogs) of human contact for extended periods.

Myth #3: Some dog breeds bite humans more than others

Statistical research by the Victorian Bureau of Animal Welfare (BAW) has shown that the major contributing factor to dog attacks in urban public places is the inadequate confinement of dogs to their property, rather than the breed of dog.  Most incidents occur on the footpath or road bordering the dog owner’s property, as a result of dogs displaying territorial aggression toward people passing by or attempting to access the front door.  If owners ensured their dogs were adequately confined to the house or back yard, over 80% of dog attack incidents in public places could be prevented.[4]

The BAW studies have not shown that ‘restricted breed dogs’ (i.e. dogs bred for fighting) are excessively represented in the incidence of dog attacks on humans.  Any dog can bite if sufficiently provoked.  However, because of the relative strength of fighting dogs and their habit of tenaciously gripping their victims with their teeth and shaking them, anecdotal evidence suggests that the risks of injury and death may be greater from these types of dogs if and when they do attack humans.

Myth #4: Feeding stray cats is being kind

A survey by Monash University in 2005 found that 22 per cent of people said they sometimes fed a cat that did not belong to them.[5]  People may feel they are being kind because they know that stray cats suffer from starvation, disease and injuries from fights with other cats. But because they are ‘unowned’, stray cats are deprived of the regular meals, shelter, grooming and veterinary care that owned cats receive.  Feeding stray cats provides people with a short-term ‘feel good factor’ that acts against the long-term welfare of the cats.  It is a form of preference failure. Being a stray cat is not a sustainable lifestyle, with an average life-expectancy of only 3 years.  So feeding them actually perpetuates the misery of these poor animals (and their kittens), which on a rational basis should either be adopted as pets or euthanased.

An adverse side-effect is that stray cats are also more likely to kill birds, possums and other native animals than owned cats, at least some of which are kept indoors overnight.  The kindest thing to do for a stray cat would be to ‘adopt’ it (but have it checked for a microchip by a vet first).  If this is not possible, contact an animal welfare organisation such as the RSPCA or the Cat Protection Society.

Myth #5: Livestock are slaughtered inhumanely in Australia

Slaughter standards in Australian abattoirs are dictated by the Australian Standard for the Hygienic Production of Meat and Meat Products for Human Consumption (AS 4696 — 2007), which requires that:

1. Animals are slaughtered in a way that prevents unnecessary injury, pain and suffering to them and causes them the least practicable disturbance; and.

2. Before killing commences, animals are stunned in a way that ensures that the animals are unconscious and insensible to pain beforehand, and do not regain consciousness or sensibility before dying.[6]

There is provision for a religious exemption under an approved arrangement that allows ritual slaughter involving the commencement of killing without prior stunning.  However, such animals must then be stunned without delay to ensure that they are rendered unconscious whilst dying.  Personally, I am opposed to such religious exemptions, on the grounds of cruelty.

Myth #6: Meat chickens are kept in cages

Many people are surprised to learn that no meat chickens (also known as broilers) are kept in cages, at least in Australia.  They are farmed in large ventilated barns or sheds where they are free to roam large distances, albeit under crowded conditions, as shown in the photograph below.  Traditionally, this has not been done for welfare reasons but to allow faster and easier collection for processing, which is usually done at night.

An RSPCA approved Australian meat chicken shed

An RSPCA approved Australian meat chicken shed

In Australia, feed lines and pans run the length of the shed and are supplied automatically by silos from outside. Water lines run the length of the shed, with drinkers at regular intervals. Water and feed are placed so that chickens are never more than about 2 metres from food and water.

Myth #7: Free range chooks live mainly outdoors

Chickens naturally prefer to live under cover from predators and bad weather. In the wild, they forage for insects and other food beneath shrubs and undergrowth, only venturing out into the open for short periods of time.

Free range chickens preferring shade (source: Wikimedia Commons)

Free range chickens preferring shade (source: Wikimedia Commons)

There are no government regulations about free-range farming practices – this is left to industry self-regulation.  Australian industry standards specify that free-range chickens only need free access to the outdoors – they don’t actually need to spend any time outside a shed to qualify as free-range.  As a result, free-range chickens don’t usually spend the bulk of their time in the open, as illustrated by the photograph above. Some free-range farms have sheds on wheels or other movable housing structures.

Myth #8: Pigs are permanently kept in sow stalls

This claim is often made by animal rights activists but is untrue.  The reason for confinement in sow stalls (gestation stalls) is to minimise early abortions as a result of stress from aggressive behaviour between adult female pigs (sows).[7]

The endorsed Australian national standards for pig farming specify a maximum confinement period of 6 weeks during the initial stages of pregnancy.  Parts of the pork industry are voluntarily introducing shorter periods, but these will require more supervision (and thus higher labour costs) to separate sows that fight.

There is also some public confusion between gestation stalls and farrowing crates, especially when photographs of the latter (see below) are described as the former.

Sow farrowing crate (source: Wikimedia Commons)

Sow farrowing crate (source: Wikimedia Commons)

Sows are moved in groups to farrowing sheds approximately one week prior to giving birth.  In Australia, a farrowing crate is only used for piglet feeding purposes.  It allows the sow less movement than a gestation stall, but provides creep areas along either side for the piglets. Adjustable rails alongside the sow slow her movement when she is lying down, thus protecting piglets from being crushed.  As soon as the piglets are weaned, the sow is moved to either a much larger pen or outdoors.

Myth #9: Sheep mulesing is cruel and unnecessary

Mulesing is the removal of wrinkled skin from the breech or breech and tail of a sheep using mulesing shears.  Until accepted alternatives are developed and the current practice can be phased out, mulesing of lambs remains an important husbandry practice in Australia for animal health, welfare and management reasons.  The principal reason is to reduce urine and faecal soiling or dag formation in the breech and tail wool; and thus minimise susceptibility to even more painful breech and tail flystrike.

Currently, cost effective chemical, management and breeding solutions are not available for all types of production systems in Australia and mulesing is a valuable tool for the prevention of breech flystrike for certain production environments and sheep types.  Although potentially painful, mulesing can be a net welfare benefit.

Available scientific research suggests that it is possible to achieve pain relief in conjunction with mulesing. Pain relief is most effectively achieved through a combination of approaches such as the pre-mulesing administration of a systemic pain relief drug, followed by a post-mulesing application of topical anaesthetic to deal with the ensuing period of pain associated with the inflammatory phase.  That is to say, a combination of short and long-acting pain relief drugs may be needed to provide more complete pain relief.[8]

Myth #10: Fish can’t feel pain

The International Association for the Study of Pain’s widely used definition states: ‘Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage’.[9]  Unlike in humans, pain is difficult to observe and measure in fish, especially in the absence of tissue damage.

Even when pain avoidance is observed experimentally in fish, a possible explanation is that it is a conditioned response to stimuli without the adverse emotional experience necessary for suffering.  Because of these observational difficulties, the conclusion that fish experience pain is often inferred on the basis of comparative neural anatomy and physiology. Some scientists are currently of the view that all higher vertebrates feel pain; and that certain invertebrates, like the lobster and octopus, might too.

The current approach in Australian animal welfare regulation is to give the fish the benefit of the doubt, and to presume until further research that fish can feel pain.  Whilst painless fishing may be almost impossible to achieve, banning fishing would also be politically impossible in a democracy.  The current regulatory approach is to minimise pain by requiring fish to be either killed or released as soon as possible after capture.

Conclusion

It may come as no surprise that I support the current scientific approach to animal welfare rather than an anthropomorphic or animal rights approach.  My main reasons for this view are:

  • Evidence-based animal welfare standards are being progressively adopted by Australian governments.
  • Such standards are more likely to be enforced and complied with than other approaches.
  • As a result, animal welfare is steadily improving in Australia.
  • This approach maintains the competitiveness of Australian agriculture.

Tim Harding B.Sc. has worked for the last 13 years as a regulatory consultant, amongst other things evaluating state and national animal welfare regulations for both domestic animals and livestock.  

References: 

[1] Warren, Katrina.  DrKatrina.com web site.

[2] Pet MD web site. Dietary Reactions in Dogs.

[3] Bradshaw, John (2011) In Defence of Dogs. Penguin Books, London.

[4] Harding, Tim (2005)  Proposed Domestic (Feral And Nuisance) Animals Regulations 2005 – Regulatory Impact Statement. Department of Primary Industries, Attwood.

[5]  http://www.theage.com.au/environment/animals/citys-stray-cat-problem-has-melbourne-throwing-a-hissy-fit-20130610-2o07j.html

[6] Browne, Gavin  (2007)  Australian Standard for the Hygienic Production of Meat and Meat Products for Human Consumption (AS 4696 — 2007). Food Regulation Standing Committee Technical Report Series 3.  CSIRO PUBLISHING / Food Regulation Standing Committee, Collingwood.

[7] Harding, Tim and Rivers, George (2006) Proposed Model Code Of Practice For The Welfare Of Animals – Pigs: Regulatory Impact Statement. CSIRO PUBLISHING, Collingwood.

[8] Harding, Tim and Rivers, George (2013) Proposed Australian Animal Welfare Standards And Guidelines – Sheep: Consultation Regulation Impact Statement. Animal Health Australia, Canberra.

[9] Bonica, John (1979) The need of a taxonomy. Pain. 1979; 6(3): 247–8.

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Introduction

Welcome to Tim Harding’s blog of writings and talks about logic, rationality, philosophy and skepticism. There are also some reblogs of some of Tim’s favourite posts by other writers, plus some of his favourite quotations and videos This blog has a Facebook connection at The Logical Place.

There are over a thousand posts here about all sorts of topics – please have a good look around before leaving.

If you are looking for an article about the Birth of Experimental Science recently published in The Skeptic magazine titled ‘Out of the Dark’, it is available here.

If you are looking for an article about the Dark Ages recently published in The Skeptic magazine titled ‘In the Dark’, it is available here.

If you are looking for an article about the Traditional Chinese Medicine vs. Endangered Species recently published in The Skeptic magazine titled ‘Bad Medicine’, it is available here.

If you are looking for an article about the rejection of expertise published in The Skeptic magazine titled ‘Who needs to Know?’, it is available here.

If you are looking for an article about Charles Darwin published in The Skeptic magazine titled ‘Darwin’s Missing Link“, it is available here.

If you are looking for an article about the Astronomical Renaissance published in The Skeptic magazine titled ‘Rebirth of the Universe‘, it is available here.

If you are looking for an article about DNA and GM foods published in The Skeptic magazine titled ‘The Good Oil‘, it is available here.

If you are looking for an article about animal welfare published in The Skeptic magazine titled ‘Creature Features‘, it is available here.

If you would like to submit a comment about anything written here, please read our comments policy.

 

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Copyright notice: © All rights reserved. Except for personal use or as permitted under the Australian Copyright Act, no part of this website may be reproduced, stored in a retrieval system, communicated or transmitted in any form or by any means without prior written permission. All inquiries should be made to the copyright owner, Tim Harding at tim.harding@yandoo.com, or as attributed on individual blog posts.

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DNA and GM foods

by Tim Harding B.Sc

(An edited version of this essay was published in The Skeptic magazine, September 2014, Vol 34 No 3, under the title ‘The Good Oil’.  The essay is based on a talk presented to the Mordi Skeptics, Tuesday 5 April 2011; and later to the Sydney Skepticamp, 30th April 2011.)

In May 2014, a farmer accused of ‘contaminating’ his neighbour’s land with genetically modified canola won a highly publicised civil case in the Western Australian Supreme Court (Marsh v. Baxter, 2014).  Although the case was about a claim of conflicting land use rather than food safety, it fired up the long-running community debate about genetically modified foods in Australia.  It also exposed a lot of misinformation and misunderstanding about DNA and genetic modification.

This essay discusses the nature and structure of DNA; together with the history of its discovery. It makes the point that artificial selection been occurring since the dawn of civilisation; and that the outcome of different methods of artificial selection is the same – modification of the genetic code by human intervention. Not only is there no evidence that genetically modified foods are unsafe to eat, but there is no mechanism by which they could be unsafe.

Brief history of DNA research

The rules of genetics were largely understood since Gregor Mendel’s ‘wrinkled pea’ experiments in the 1860s but the mechanisms of inheritance remained a mystery.   Charles Darwin knew in the 1850s there must have been such a mechanism (but his later speculations about it – called pangenesis – were wrong).[1]  The units of inheritance were called genes, but it was not understood where genes were located in the body or what they physically consisted of.

After the rediscovery of Mendel’s work in the 1890s, scientists tried to determine which molecules in the cell were responsible for inheritance.  In 1910, Thomas Hunt Morgan argued that genes are on chromosomes, based on observations of a sex-linked white eye mutation in fruit flies.  In 1913, his student Alfred Sturtevant used the phenomenon of genetic linkage to show that genes are arranged linearly on the chromosome.  It was soon discovered that chromosomes consisted of DNA and proteins, but DNA was not identified as the gene carrier until 1944.

Watson and Crick’s breakthrough discovery of the chemical structure of DNA in 1953 finally revealed how genetic instructions are stored inside organisms and passed from generation to generation.[2]  In the following years, scientists tried to understand how DNA controls the process of protein production. It was discovered that the cell uses DNA as a template to create matching messenger RNA (a single-strand molecule with nucleotides, very similar to DNA). The nucleotide sequence of a messenger RNA is used to create an amino acid sequence in protein; this translation between nucleotide and amino acid sequences is known as the genetic code.

DNA structure

The molecular basis for genes is deoxyribonucleic acid (DNA) a double-stranded molecule, coiled into the shape of a double-helix.  DNA is composed of twin backbones of sugars and phosphate groups joined by ester bonds.  These backbones hold together a chain of nucleotides, of which there are four types: adenine (A), cytosine (C), guanine (G), and thymine (T).  Genetic information in all living things exists in the sequence of these nucleotides, and genes exist as stretches of sequence along the DNA chain.[3]  Each nucleotide in DNA preferentially pairs with its partner nucleotide on the opposite strand: A pairs with T, and C pairs with G using weak hydrogen bonds.  Thus, in its two-stranded form, each strand effectively contains all necessary information, redundant with its anti-parallel partner strand.  This structure of DNA is the physical basis for inheritance: DNA replication duplicates the genetic information by enzymes splitting the strands (like a zipper) and using each strand as a template for synthesis of a new partner strand.

Chemical structure of DNA (Source: Wikimedia Commons)

Chemical structure of DNA (Source: Wikimedia Commons)

The sequence of these nucleotides A, C, G and T is a code, similar to the binary digital code used in computing.  When you consider that all the instructions for everything that computers can produce: text, calculations, music and images is stored as a binary sequence of ones and zeros, it is not hard to conceive how the instructions for making and operating living organisms can be stored as a four letter code.

Genes are arranged linearly along very long chains of DNA sequence, which comprise the chromosomes.  In bacteria, each cell usually contains a single circular chromosome, while eukaryotic organisms (including plants and animals) have their DNA arranged in multiple linear chromosomes.  These DNA strands are often extremely long; the largest human chromosome (No. 1), for example, is about 247 million base pairs in length. The full set of hereditary material in an organism (usually the combined DNA sequences of all 46 chromosomes in humans) is called the genome (approx. 3 billion base pairs in humans).

The genetic code is the set of rules by which information encoded in genetic material (DNA or mRNA sequences) is translated into proteins (amino acid sequences) by living cells.  The code defines a mapping between tri-nucleotide sequences, called codons, and amino acids. With some exceptions, a triplet codon in a nucleic acid sequence specifies a single amino acid.[4]

Translation of genetic code into proteins (Source: Wikimedia Commons)

Translation of genetic code into proteins (Source: Wikimedia Commons)

However, the human genome contains only ca. 23,000 protein-coding genes, far fewer than had been expected before its sequencing.  In fact, only about 1.5% of the genome codes for proteins, while the rest consists of non-coding RNA genes, regulatory sequences, introns, and noncoding DNA (once known as ‘junk DNA’). Genetic recombination during sexual reproduction involves the breaking and rejoining of two chromosomes (one from each parent) to produce two new rearranged chromosomes, thus providing genetic diversity and increasing the efficiency of natural selection.

Genetic modification

One of the biggest public misunderstandings is about the very term ‘genetic modification’.  Genes can be modified in 2 main ways:

Artificial selection can occur in 4 main ways:

  • traditional plant and animal breeding (long-term);
  • mutagenesis (random exposure to chemical or radiological mutagens);
  • RNA interference (switching genes on or off);
  • genetic engineering (short-term) – the targeted insertion or deletion of genes in the laboratory (which cannot easily be achieved by other methods).

The end result of the different methods of artificial selection is the same – modification of the genetic code by human intervention.  All DNA, whether modified naturally or artificially, is biochemically and nutritionally the same.  The only difference is in the genetic code, that is, the sequence of the bases G, C, T and A.  In other words, DNA is DNA – there are no such thing as ‘natural DNA’ and ‘artificial DNA’.

They are all ways of artificially modifying genes, yet for some illogical reason plant and animal breeding is not usually referred to in the media as genetic modification – possibly because it started a long time (c. 11,000 years ago) before genetics was understood.  However, to avoid any confusion, in this paper I will refer to genetic modification of foods by genetic engineering as genetically engineered foods (GE foods).

As a result of artificial selection, all farmed foods we eat today have been genetically modified by humans via plant and animal breeding.  This includes all meats except for wild game and kangaroo; and most farmed fish such as salmon.

Similarly all plants we eat (vegetables, fruits,  nuts, herbs and spices) have been genetically modified by humans.  Many varieties bear little resemblance to their original wild forms.  A wheat grain is a genetically modified grass seed.  Can anybody think of a plant food that has not been modified by humans?  (The only ones any of us at the meetup could think of were bush tucker, which is rarely found in Australian shops or supermarkets.  Seaweed was later suggested at the Sydney Skepticamp).

Whenever we eat and digest proteinaceous food, the DNA inside the food gets broken down into single nucleotides before absorption in the small intestine, destroying the genetic code anyway.  It is therefore logically impossible for any changes in the genetic code, whether artificial or natural, to make DNA unsafe to eat.

Not only is it logically impossible, but there is no empirical evidence that genetically modified foods are harmful.  The technology to produce genetically engineered (GE) plants is now over 30 years old, yet in all that time there has not been a single instance of anybody becoming ill, let alone dying, as a result of eating GE foods.

In a recent major review of the scientific literature on last 10 years of the world’s GE crop safety research, the reviewers conclude that ‘the scientific research conducted so far has not detected any significant hazard directly connected with the use of GE crops’.  The authors further believe that ‘genetic engineering and GE crops should be considered important options in the efforts towards sustainable agricultural production’ (Nicolia et al, 2013).

GE foods

GE foods can be produced by either cisgenesis (within the same species) or transgenesis (from different species).[5]  However, the point needs to be made that the human genome naturally contains genes resulting from billions of years of evolution – even genes from our fishy ancestors.  A substantial fraction of human genes seem to be shared among most known vertebrates.  For example, the published chimpanzee genome differs from that of the human genome by 1.23% in direct sequence comparisons.  We also share many genes with plants.

“The real question here is not whether there is a GMO tomato with a fish gene, but who cares? It’s not as if eating fish genes is inherently risky—people eat actual fish. Furthermore, by some estimates people share about 70 percent of their genes with fish. You have fish genes, and every plant you have ever eaten has fish genes; get over it.”[6]

GE foods were first put on the market in the early 1990s.  Typically, genetically modified foods are transgenic plant products: soybean, corn, canola, and cotton seed oil.  

GE genes may be present in whole foods, such as wheat, soybeans, maize and tomatoes.  The first commercially grown genetically modified whole food crop was a tomato (called FlavrSavr), which was modified to ripen without softening, in 1994.  These GE whole foods are not presently available in Australia.  GE food ingredients are, however, present in some Australian foods.  For example, soy flour in bread may have come from imported GE soybeans.[7]

In addition, various genetically engineered micro-organisms are routinely used as sources of enzymes for the manufacture of a variety of processed foods. These include alpha-amylase from bacteria, which converts starch to simple sugars, chymosin from bacteria or fungi that clots milk protein for cheese making, and pectinesterase from fungi which improves fruit juice clarity.

sugar

Genetic engineering can also be used to increase the amount of particular nutrients (like vitamins) in food crops. Research into this technique, sometimes called ‘nutritional enhancement’, is now at an advanced stage. For example, GE golden rice is an example of a white rice crop that has had the vitamin A gene from a daffodil plant inserted. This changes the colour and the vitamin level for countries where vitamin A deficiency is prevalent. Researchers are especially looking at major health problems like iron deficiency. The removal of the proteins that cause allergies from nuts (such as peanuts and Brazil nuts) is also being researched.[8]

Animal products have also been developed, although as of July 2010 none are currently on the market.  However, human insulin has been produced using GE E.coli bacteria since 1978.  In 2006 a pig was controversially engineered to produce omega-3 fatty acids through the expression of a roundworm gene.  Researchers have also developed a genetically-modified breed of pigs that are able to absorb plant phosphorus more efficiently, and as a consequence the phosphorus content of their manure is reduced by as much as 60%.

Once again, there is no evidence of any person being harmed by eating genetically engineered foods.  The reasons why genetically engineered whole foods are not yet available in Australia are political or emotional rather than scientific.

Benefits of GE foods

There is a need to produce inexpensive, safe and nutritious foods to help feed the world’s growing population. Genetic engineering may provide:

  • Sturdy plants able to withstand weather extremes (such drought);
  • Better quality food crops;
  • Higher nutritional yields in crops;
  • Inexpensive and nutritious food, like carrots with more antioxidants;
  • Foods with a greater shelf life, like tomatoes that taste better and last longer;
  • Food with medicinal (nutraceutical) benefits, such as edible vaccines – for example, bananas with bacterial or rotavirus antigens;
  • Crops resistant to disease and insects and produce that requires less chemical application, such as pesticide and herbicide resistant plants: for example, GE canola.[8]

Objections to GE foods

So why is there such significant opposition to GE foods from some vocal lobby groups? Critics have objected to GE foods on several grounds, including:

  • the appeal to nature fallacy (natural products are good and artificial products are bad);
  • alleged but unproven safety issues, (there is no evidence of any adverse health effects, including allergies, in the 20 years since GE foods became available);
  • marketing concerns about ‘contamination’ of so-called organic food crops by GMOs (such as in the Marsh -v-Baxter case);
  • ecological concerns about the spread of GMOs in the wild, and
  • economic or ideological concerns raised by the fact that these organisms are subject to intellectual property rights usually held by big businesses.

The only one of these objections that may have any scientific legitimacy is the ecological concern about the spread of GMOs in the wild.  However, the use of GE technology is highly regulated by Australian governments and any such ecological concerns are fully taken into account.

Current food regulations in Australia state that a GE food will only be approved for sale if it is safe and is as nutritious as its conventional counterparts.  Food regulatory authorities require that GE foods receive individual pre-market safety assessments prior to use in foods for human consumption.  The principle of ‘substantial equivalence’ is also used.  This means that an existing food is compared with its genetically modified counterpart to find any differences between the existing food and the new product.  An important to note is that Australia has the most rigorous food safety testing regime in the world, and that GE foods are tested even more rigorously than non-GE foods. Foods certified as organic or biodynamic should not contain any GE ingredients, according to voluntary organic food industry guidelines.

Here is a list of 114 peer-reviewed articles and meta reviews, mostly published in moderate to high impact factor journals that support the safety of GMO crops over a wide range of hypotheses.  The consensus position of the American Association for the Advancement of Sciences on GM foods is:

“Indeed, the science is quite clear: crop improvement by the modern molecular techniques of biotechnology is safe… The World Health Organization, the American Medical Association, the U.S. National Academy of Sciences, the British Royal Society, and every other respected organization that has examined the evidence has come to the same conclusion: consuming foods containing ingredients derived from GM crops is no riskier than consuming the same foods containing ingredients from crop plants modified by conventional plant improvement techniques.”

References

American Association for the Advancement Of Science (2012). Statement by the AAAS Board of Directors On Labeling of Genetically Modified Foods. 20 October 2012.

Better Health Channel (2011) Fact Sheet – Genetically modified foods www.betterhealth.vic.gov.au Melbourne: State of Victoria.

Darwin, Charles (1868),The Variation of Animals and Plants under Domestication (1st ed.), London: John Murray.

Lynas, Mark (29 April 2013) Time to call out the anti-GMO conspiracy theory.  Mark Lynas speech hosted by the International Programs – College of Agriculture and Life Sciences (50th Anniversary Celebration) , and the Atkinson Center for a Sustainable Future, Cornell University.

Marsh -v-Baxter [2014] WASC 187 (28 May 2014).

Nocolia, A., Mazo, A., Veronesi, F., and Rosellini (2013) ‘An overview of the last 10 years of the genetically engineered crop safety research’. Critical Reviews in Biotechnology. Informa Healthcare USA Inc. ISSN: 0738-8552 (print) 1549-7801 (electronic).

Skeptical Raptor’s Blog. What does science say about GMO’s–they’re safe. Updated 19 November 2014.

Novella, Stephen (2014) ‘No Health Risks from GMOs’. The Science of Medicine .Volume 38.4, July/August 2014.

Watson J.D. and Crick F.H.C. (1953) A Structure for Deoxyribose Nucleic Acid. Nature 171 (4356): 737–738.

Other information is from Wikipedia and the author’s knowledge as a former biochemist.  (According to convention, anonymous Wikipedia pages, whilst thought to be mostly factually correct, are not citable as references).


[1] Darwin, 1868.

[2] Watson and Crick, 1953.

[3] Viruses are the only exception to this rule—sometimes viruses use the very similar molecule RNA instead of DNA as their genetic material.

[4] Not all genetic information is stored using the genetic code. All organisms’ DNA contains regulatory sequences, intergenic segments, and chromosomal structural areas that can contribute greatly to phenotype by controlling how the genes are expressed.  Those elements operate under sets of rules that are distinct from the codon-to-amino acid paradigm underlying the genetic code.

[5] For example, the gene from a fish that lives in very cold seas has been inserted into a strawberry, allowing the fruit to be frost-tolerant.  However, this has not as yet been done for currently available commercial food crops.

[6] Novella, 2014.

[7] Better Health Channel, 2011.

[8] Better Health Channel, 2011.

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