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Bambi or Bessie: Are wild animals happier?

The views expressed are those of the author and are not necessarily those of Scientific American.


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We, as emotional beings, place a high value on happiness and joy. Happiness is more than a feeling to us – it’s something we require and strive for. We’re so fixated on happiness that we define the pursuit of it as a right. We seek happiness not only for ourselves and our loved ones, but also for our planet and its creatures.

Sure, campaigns for Animal Liberation take this to the extreme. They believe that all animals "deserve to lead free, natural lives." But extreme animal activists aren’t the only ones who think animal happiness is important. They’re not even the only ones that think animals have some level of right to be free. Many people are against zoos because they feel it’s wrong to keep animals in captivity. I’ve even heard arguments for hunting as an alternative to farming livestock, because at least the wild animals lived happily prior to their death, while the poor cows or chickens suffered because they are never allowed to be free. And let’s be honest: who didn’t watch Free Willy and feel, at least for a moment, that every animal we have ever put in a cage or a tank should be let go?

The core idea behind all of this is the belief that animals in nature are truly happier than animals in captivity, even than domesticated ones. But are they? I mean, really?

Happiness is hard enough to define in people, let alone in an animals. You can’t just ask them how they are feeling. Instead, we tend to qualify happiness in animals as a lack of chronic stress. Stress, unlike happiness, is very easy to measure. You can look for decreases in overall health in just about any kind of creature. You can keep an eye out for neurotic behaviors, and measurements of hormone levels of cortisol, norepinephrine, adrenaline and other "stress" hormones provide a quantified means of measuring stress. Though lack of stress doesn’t guarantee "happiness", it’s the closest we can get.

The idea, in particular, that livestock could be happier than wild animals is a hard thing to grasp, because as people, we can’t imagine being kept simply to be used. The idea of having no control over how we are used by another, even if we’re given everything we want now, seems unbearably cruel – but it’s not the same for animals. Domesticated animals don’t feel stress about the future, because they don’t have an understanding of their future in the same way we do. A cow doesn’t live a more stressed or unhappy life than a dog or a deer because it is destined to be killed for its meat. Cows aren’t upset that they will end up as steaks because, as Michael Pollan phrased it, "in a bovine brain the concept of nonexistence is blissfully absent."

So the real question becomes whether a domesticated or captive animal is more, less, or as happy in the moment as its wild counterpart. There are a few key conditions that are classically thought to lead to a "happy" animal by reducing undue stress. These are the basis for most animal cruelty regulations, including those in the US and UK. They include that animals have the ‘rights’ to:

- Enough food and water

- Comfortable conditions (temperature, etc)

- Expression of normal behavior

Now, the factory farm industry isn’t known for its strict adherence to these standards. But many farms do care for their animals well, and the vast majority of pet owners do, too. Domesticated and other captive animals, by and large, live lives where they are well fed, free of curable diseases, in comfortable conditions where they are able to be themselves, at least to a certain extent.

When it comes to wild animals, though, only the last is guaranteed. They have to struggle to survive on a daily basis, from finding food and water to another individual to mate with. They don’t have the right to comfort, stability, or good health. Moreover, when the ‘expression of normal behavior’ encroaches upon people, whether it be raiding trash cans or attacks, that last one gets thrown out the window, too. By the standards our governments have set, the life of a wild animal is cruelty.

But even still – are they happier? First and foremost, it’s important to realize that not all animals are the same. Domesticated animals are fundamentally different from their wild counterparts: they are not just wild animals that have been raised in captivity; they have undergone evolutionary changes through artificial selection that have altered their bodies, brains and behaviors.

We have no evidence whatsoever that wild animals are, in any way, happier than domesticated ones which are treated well. One of the consequences of domestication is a decrease in stress across the board. Studies have shown that domesticated animals are less stressed to begin with, and freak out less in response to stressful things like unfamiliar habitats or predators. Guinea pigs, for example, have serum epinephrine and norepinephrine concentrations that are four to eight times lower than their wild counterparts, cavies. They also have a reduced response when intentionally stressed by being placed in an unfamiliar cage. Similar results have been found in cats, rats, ducks and even fish. In fact, a decreased stress response compared to wild counterparts has been found in every single domesticated species that has been studied.

It’s more than just how they were raised, too. A similar study raised cavies in captivity for 30 generations and compared their behavior and hormone levels to wild-raised cavies and domesticated guinea pigs. They found that the behavioral differences between domesticated and wild animals held even after 30 generations of captive rearing. Just like before, the wild animals had both a higher basal stress levels and stress responses. Even the captive-raised cavies had higher levels of norepinephrine and epinephrine from the get-go. Furthermore, both the wild and captive-raised cavies showed a markedly higher stress response to an unfamiliar environment than the domesticated guinea pigs.

When we domesticated animals, we forever altered how they respond to their environment. We reduced their sensitivity to things that are otherwise very upsetting to their wild relatives – like interacting with us. The side effect of this is that domesticated animals are predisposed to being happier than their wild counterparts, in spite of captivity.

"To think of domestication as a form of enslavement or even exploitation is to misconstrue the whole relationship, to project a human idea of power onto what is, in fact, an instance of mutualism between species," Pollan explains – and he’s right.

Stress is important for surviving in the wild. Stress tells you you’re in danger, and provides your body with the boost of performance needed to get out of the situation. The attenuated stress response exhibited by domesticated species doesn’t just make them easier to keep happy in captivity, it makes them less fit to live outside of it. The vast majority of domesticated animals wouldn’t survive in the wild, period. As the 19th century philosopher Leslie Stephen put it, "The pig has a stronger interest than anyone in the demand for bacon. If all the world were Jewish, there would be no pigs at all."

Releasing a domesticated animal into the wild isn’t ‘freeing’ it – it’s placing a mostly defenseless creature in an unfamiliar and uninviting habitat that it is simply not equipped to deal with. Whether you want to morally condemn the people who domesticated animals in the first place is up to you, but ‘liberating’ them now simply isn’t in their best interests.

These data also suggest something that might seem a bit radical: if we follow the guidelines of care that provide food, water, comfort, and necessary items for behavioral expression, domesticated animals are not only likely to be as happy as their wild relatives, they’re probably happier. This applies to livestock as much as it does to a guinea pig, in spite of the fact that we raise the livestock solely to be killed and eaten.

But what about captive animals from non-domesticated lineages? Are animals that haven’t undergone the evolutionary changes of domestication happier in the wild?

That’s a much harder question to answer, in part because we don’t have good baselines for wild animals. Until recently, studying stress hormone levels meant drawing blood – which, as you can image, is a stressful event in and of itself for a wild animal. However, newer methods have been developed that can measure the stress hormone levels in scat and urine left by wild animals, so it’s now possible to get an assessment of stress that doesn’t involve capturing the animal first.

What we do know so far is that evidence suggests wild animals can be as happy in captivity as they are in nature, assuming they are treated well. Confinement alone doesn’t mean an animal is automatically worse off. If we give an animal all the good things they would have in the wild (food and water, fellow members of their species, a certain amount of space) and take away that stresses or hurts them (predators, parasites, extreme weather), then it can live just as happily in an enclosure. Zoo animals with proper care and enrichment, for example, have similar hormone profiles, live longer, eat better, and are healthier than their wild counterparts. Why? Because life in the wild is hard. In captivity, it’s easy.

We also know that when we change our care of an animal to try to decrease stress, we succeed. Stress hormone levels drop, for example, when leopards are given a larger enclosure or things to play with. This means we are able to modify our standards of care to ensure that any animals we place in captivity, domesticated or wild, are as happy as they can be.

So overall, are wild animals happier? While there is a lot more science that can be done to answer that question, the answer seems to be: no, not if they’re cared for well in captivity. The more we study animal behaviors, the better we get at figuring out what they need to pursue their own happiness, even when they are not allowed to be ‘free.’

I want to be clear that this doesn’t mean I’m making any moral judgements about zoos, farming, hunting, animal testing, veganism, or anything else this information might apply to. For all of those topics, the suffering or lack thereof during life is only one of many considerations that factors into morality. I have my own personal feelings about these topics, but that’s not the point of this post. I’m just stating the facts about what we know of animal happiness in different conditions – how you interpret their meaning on a broader level is up to you.

However, I will inject a little of my own opinion. I believe this whole idea that wild animals are happier is due to what I call our ‘natural bias’. What do I mean by that? Well, we tend to idealize nature. When we picture the wild world, we see lush forests full of brightly-colored, singing birds, with monkeys swinging from branch to branch. We imagine vast prairies with herds of antelope and zebra grazing peacefully while a pack of lions naps lazily in the shade. Even when we do imagine the more gruesome aspects of the wild, we see them as OK or better than what we do because it’s "natural."

This bias for what is "natural" is pervasive, affecting our judgement on everything from sexual orientation and medical care to farming practices and clothing fibers. But there is nothing inherently better about something being natural, and the idea that something that occurs in nature without us is somehow better than something we have altered or taken part in is a dangerous fallacy (the use of Rotenone by organic farms, a natural but unbelievably awful pesticide that was still usable in Europe until 2009, is a prime example). I love the natural world. I became a biologist because of my passion for all kinds of creatures, and conservation is one of the core tenants of what I do on a daily basis. But while I appreciate and fight for the beauty and brilliance that is our planet, I firmly believe we need to see ourselves as a part of it, not above or below it. We are, after all, "natural," too.

Image of Bambi, via Wikimedia Commons.

Resources:

1. Franklin D. McMillan (2008). Chapter 16. Do Animals Experience True Happiness? Mental Health and Well-Being in Animals DOI: 10.1002/9780470384947.ch16

2. Möstl E, & Palme R (2002). Hormones as indicators of stress. Domestic animal endocrinology, 23 (1-2), 67-74 PMID: 12142227

3. Pollan, Michael. "An Animal’s Place" The New York Times Magazine, Nov 10, 2002 PDF

4. Künzl, C. (1999). The Behavioral Endocrinology of Domestication: A Comparison between the Domestic Guinea Pig (Cavia apereaf.porcellus) and Its Wild Ancestor, the Cavy (Cavia aperea) Hormones and Behavior, 35 (1), 28-37 DOI: 10.1006/hbeh.1998.1493

5. MARTIN, J. (1978). Embryonic Pituitary Adrenal Axis, Behavior Development and Domestication in Birds Integrative and Comparative Biology, 18 (3), 489-499 DOI: 10.1093/icb/18.3.489

6. Lepage O, Overli O, Petersson E, Järvi T, & Winberg S (2000). Differential stress coping in wild and domesticated sea trout. Brain, behavior and evolution, 56 (5), 259-68 PMID: 11251318

7. Künzl, C. (2003). Is a wild mammal kept and reared in captivity still a wild animal? Hormones and Behavior, 43 (1), 187-196 DOI: 10.1016/S0018-506X(02)00017-X

8. Hill, S., & Broom, D. (2009). Measuring zoo animal welfare: theory and practice Zoo Biology DOI: 10.1002/zoo.20276

9. BROWN, J. (2006). Comparative endocrinology of domestic and nondomestic felids Theriogenology, 66 (1), 25-36 DOI: 10.1016/j.theriogenology.2006.03.011

About the Author: Christie Wilcox is a science writer who moonlights as PhD student in Cell and Molecular Biology at the University of Hawaii at Manoa. Follow Christie on her blog, Observations of a Nerd, or on Facebook or Twitter.

The views expressed are those of the author and are not necessarily those of Scientific American.






Comments 21 Comments

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  1. 1. hanmeng 10:58 am 04/12/2011

    Great article. Now let’s put humans in captivity instead of letting them run around wild like beasts. Put me in charge–I’ve got your best interests at heart!

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  2. 2. weltschmerz 11:02 am 04/12/2011

    I wonder why you put quotes in "animals have the ‘rights’" What makes our rights (whatever that means, although I don’t really believe it means something noble and non-trivial) different from theirs? How is a our "right" to, say, speak our mind, *not* susceptible of being put in quotes?

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  3. 3. Gremmie64 11:21 am 04/12/2011

    Thank you for writing a wonderful layman-language article. It can only be hoped that some of what you have to say will get through to those who have never interacted with domestic animals beyond cats, dogs, and guinea pigs, or any really wild animals. I have had a terrific and long life which granted me the knowledge and opportunity to interact with, and `own’ over 110 species of both wild (some rare and endangered) and domestic animals. There were also the real wild animals who shared with us the land where we lived. Only very rarely did we have minor predation from our wild neighbors. Yes, we too are `natural’, and with some knowledge and consideration, it is quite possible to live harmoniously with the naturally wild.

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  4. 4. gnarly old dude 11:36 am 04/12/2011

    Of course, as with any theory, test it for validity. So open the gate and watch their choice.

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  5. 5. laurenecantrell 11:56 am 04/12/2011

    This is a topic I have carefully considered over countless hours in the last few years through my undergraduate studies in biological and animal sciences. I agree with this article completely. Anthropomorphism or placing human characteristics on non-human animals is causing a lot of emotional arguments to break out between the scientific and non-science communities. I just wish more people would look at facts and evidence before pointing the proverbial finger at scientists and claiming they are cruel, abusers of animals. It’s an uphill battle — thank you for laying out this side of the argument so eloquently!

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  6. 6. DonPaul 1:04 pm 04/12/2011

    The fundamental premise that you can measure “happiness” by measuring stress is deeply flawed. Stress is related to happiness, but that does not make it a measure. If you were to remove all stress from an animal it will become extremely bored just as a human would. No, I think happiness arises in all animals including humans when biological drives meet challenges and then are successfully mastered. In other words, animals have a NEED for stress and success similar to the human kind. Having raised a few cattle, and having an interest in such things, I am willing to assert that they have personalities just as diverse as humans. Some are indeed content to muddle along with “food and water, fellow members of their species, a certain amount of space”, at the other extreme there will be some that remain unhappy and will be intent on exploring a wider world no matter how much comfort they are allotted. For any given animal, happiness will follow from an appropriate balance between stresses and successful responses.
    http://www.mindmadereal.com

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  7. 7. robert schmidt 8:04 pm 04/12/2011

    It reminds me of a study done many years ago in which they taught chickens to peck a button to cause a moving wall in their cage to move outward thereby enlarging their living space. Afterwards the wall very slowly moved back in. The chickens could peck the button any time they liked. The results were interesting. The chicken seemed to prefer a cage that was larger than the farmers thought they needed but smaller than the animal rights groups thought they needed. When in doubt, ask the animals.

    I think one of the key assumptions to this article is that the animals are well kept, which is not always the case. Often times it is very difficult to provide the right conditions for an animal so that shouldn’t be dismissed. Otherwise I agree with the article, the assumption that animals want to be free, is generally nothing more than a naturalists fallacy. How free would you want to be if you were surrounded by predators?

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  8. 8. jtdwyer 11:35 pm 04/12/2011

    Very well done – thanks. However, it is the increasing density of our own population that imposes increasing constraints on the availability of habitat for animals, both wild and domesticated.

    The human population of the world has quadrupled since 1900 and will soon have tripled since 1950. The U.S. Census Bureau optimistically expects the now largest population ever assembled to only increase by about 33% by 2050, from less than 7 billion people now to more than 9 billion.

    People have also been migrating to urban environments during this same period, so that the population living in urban environments within 50 miles of a sea coast now exceeds the largest human population that ever existed prior to 1900.

    Perhaps the humanity of crowding billions of undomesticated humans into cubicles should also be considered…

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  9. 9. NNNLLL 3:38 am 04/13/2011

    This statement is absolute nonsense: "Cows aren’t upset that they will end up as steaks because, as Michael Pollan phrased it, ‘in a bovine brain the concept of nonexistence is blissfully absent.’" Cows do know they are going to get killed; they do understand the concept of nonexistence and death; and they do mourn their death just like us. I don’t like stupid pundits give us false information.

    Regarding animal happiness in the wild, I guess they live in hell especially animals at the bottom of food chain constantly live in scare and almost all of them brutally get killed. Probably they don’t have time to be unhappy since it has been replaced by scare (at least for many animals). But it does not mean animals in captivity are happy; many caged animals especially caged birds suffer a lot.

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  10. 10. okwhen 12:11 am 04/14/2011

    Wild animals with large roaming areas for instance cats, bears, wolves, elephants seem from my uneducated viewpoint extremely uneasy in cages. They continuously pace to the point of obsession. To me this seem extremely stressful and unhealthy. Another observation, why do many animals have much longer life expectancy in the while than in captivity. For example, dolphins live on an average of 45 years in the wild and in captivity the story is more complicated. Over half of dolphins captured die within 90 days. Of the survivors half of then die in the next two years and the lucky ones live 5 years. This is why I refuse to pay animals abusers a.k.a. aquariums parks to display these creatures.

    The author seemed to miss the obvious in my opinion. I give little credibility for any scientist or researcher to omit the life expectancy in both conditions. As I have stated, this is not my area of expertise however, as an observant individual that is well educated and read, this article is pure propaganda.

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  11. 11. PerBothner 12:35 pm 04/16/2011

    The comment that would be no pigs if we stopped farming them is completely mistaken. There are plenty of wild pigs, which do quite well, thank you: At least in California they’re considered a pest which can be hunted year-round. And these wild pigs all come from escaped domesticated pigs.

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  12. 12. Knative 1:28 pm 04/16/2011

    The local zoo, here in Michigan, recently redesigned their lion cage. Made it bigger (it’s one of the biggest in the country now), and the lions seem happy and stress free. The zoo also got some chimps a few years back. They also seem to enjoy their lives as well, because all they do all day is play, plus there’s a bunch of ‘em.
    However, the bears, wolverines, cougars, and snow leopards still seem a bit stir crazy because their cages are old. The zoo is in the process of renovating those exhibits, and it’s going to add some more (polar bears and whatnot).
    Good to know that my patronage of said zoo is probably ethically sound, because I enjoy zoos.

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  13. 13. Username4242 8:45 pm 04/17/2011

    It would be nice if some of you people would read the article before invoking knee-jerk responses that were dealt with already.

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  14. 14. Username4242 8:46 pm 04/17/2011

    That said, I very much enjoyed this article.

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  15. 15. clothesmoth 12:21 pm 04/18/2011

    Excellent article but I keep chickens and feel that a degree of anthropomorphizing is useful to help me understand what they think is natural for them. Chickens are curious and like to be busy all the time. They like stimulation not a zero stress life. I believe happiness involves making choices and decisions even if you are a chicken. Boredom is what I try to avoid and empathize with zoo animals who have insufficient space and insufficient choices. If man is going to manage the lives of animals he/she needs to do a better job of understanding what they need to live within their instincts and natural capacities. More research and more responsibility please. And more good thoughtful articles like this one.

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  16. 16. bovinity 9:28 am 04/24/2011

    I am a zoo professional and I can tell you with certainty that when an animal leaves its home enclosure, it is often to frantic to get back to familiar territory. It distinctly reminds me of my own house cats who think they want to go outside by darting out the door and then freeze with fear when out in the big scary world! Our first method in dealing with an animal out of its enclosure is to make sure it has a clear path back since that is often where it wants to go.

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  17. 17. bovinity 9:30 am 04/24/2011

    And what research are you citing that demonstrates that cattle understand the concepts of non-existence and death?

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  18. 18. jdd_london 8:21 am 04/26/2011

    My academic background is psychology but I have spent a considerable amount of my professional time involved in zoological collections so perhaps can comment with some professional rather lay insight into this issue.

    First and foremost I am basing my views on animals being care for in well managed establishments with experience care takers. Of course, one can find animals with comprised welfare particularly in areas of the world where there is no legal welfare requirements are codified by law. However, this is and never should be consider the norm or best practise.

    I would first challenge the idea that animals such as cats, bears, wolves and elephants automatically display pacing behaviour and other stereotypical behaviour as a matter of course. In modern animal exhibits and caretaking systems this rarely take place and if it does the problem could be historical from the animals experience if it was kept in appropriate environments in the past. This issue was researched in regards to bears in the UK by Dr Alison Ames in 1992 for the Universities Federation for Animal Welfare.

    Your comments of life-expectancy are interesting as all the animals above mentioned animals appear to met or exceed their wild counterparts’ survivorship where comparative data exists and has been researched.

    It is also interesting you should also cite dolphins in your observation. It is a common misconception that animals such as bottlenose dolphins (the most commonly maintain cetacean in aquaria) life-expectancy (survivorship) is compromised by captivity. This is false. There have been a number of studies done in this area and these have also appeared in peer-review journals such as Marine Mammal Science.

    There is a nice overview of this research here including referenced to the source material which was last reviewed in 2000:

    http://www.rosmarus.com/Download/Survival.pdf

    The idea that most dolphins do not live beyond 5 years in captive care in good well run establishments is untrue – I would further point out that in both the USA and mainland Europe the majority of dolphins are acquired from captive breeding programmes and no animals have been acquired from wild capture for many years.

    From my professional perspective I found Christie Wilcox article well research and far being propaganda.

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  19. 19. jdd_london 8:23 am 04/26/2011

    From my professional experience they tend to stay in their enclosures and if they do leave they tend to want to return.

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  20. 20. jdd_london 5:12 am 04/27/2011

    My academic background is psychology but I have spent a considerable amount of my professional time involved in zoological collections so perhaps can comment with some professional rather lay insight into this issue.

    First and foremost I am basing my views on animals being care for in well managed establishments with experience care takers. Of course, one can find animals with comprised welfare particularly in areas of the world where there is no legal welfare requirements are codified by law. However, this is and never should be consider the norm or best practise.

    I would first challenge the idea that animals such as cats, bears, wolves and elephants automatically display pacing behaviour and other stereotypical behaviour as a matter of course. In modern animal exhibits and caretaking systems this rarely take place and if it does the problem could be historical from the animals experience if it was kept in appropriate environments in the past. This issue was researched in regards to bears in the UK by Dr Alison Ames in 1992 for the Universities Federation for Animal Welfare.

    Your comments of life-expectancy are interesting as all the animals above mentioned animals appear to met or exceed their wild counterparts’ survivorship where comparative data exists and has been research.

    It is also interesting you should also cite dolphins in your observation. It is a common misconception that animals such as bottlenose dolphins (the most commonly maintain cetacean in aquaria) life-expectancy (survivorship) is compromised by captivity. This is false. There have been a number of studies done in this area and these have also appeared in peer-review journals such as Marine Mammal Science.

    There is a nice overview of this research here including referenced to the source material which was last reviewed in 2000:

    http://www.rosmarus.com/Download/Survival.pdf

    The idea that most dolphins do not live beyond 5 years in captive care in good well run establishments is untrue – I would further point out that in both the USA and mainland Europe the majority of dolphins are acquired from captive breeding programmes and no animals have been acquired from wild capture for many years. That fact that you call those who care for these animals in captive abusers is unfortunately and disingenuous.

    From my professional perspective I found Christie Wilcox article well research and far being propaganda.

    Link to this
  21. 21. pfgetty 8:50 pm 05/6/2011

    this, from Michael Ruppert:

    Let’s start with what I consider the most-obvious proof that the Obama administration is lying. It comes from a world-class microbiologist who allowed me to use this quote on condition of anonymity. The simple proof of his accuracy is to just ask any microbiologist experienced in DNA sequencing about his statement. There are tens of thousands of them around the world.

    Here is what he wrote me:

    I am a molecular biologist and I’ve built a lucrative career in human genetics. I have run one of the world’s largest and most productive DNA genotyping facilities and now I am helping to build the global market for clinical whole human genome sequencing for the world’s largest human genome sequencing facility. I have worked with the absolute best genome scientists from the military, academia, medicine, and industry from around the world. I know DNA. And, one thing I know about DNA is that you cannot, repeat CANNOT: take a tissue sample from a shot-in-the-noggin-dead-guy in a north central Pakistan special forces op, extract the DNA, prepare the DNA for assay, test the DNA, curate the raw DNA sequence data, assemble the reads or QC the genotype, compare the tested DNA to a reference, and make a positive identity determination…. all in 12 hours- let alone transport the tissue samples all the places they’d need to have gone in order to get this done.

    Some might try to argue that ruggedized, field ready kits could test a DNA sample- which is true if one is attempting to determine the CLASS of a bacteria. It is not true if one is trying to determine the specific identity of an individual. Any way you slice it, the real work would require days, and I find it unlikely (although not impossible) that an aircraft carrier would have a laboratory outfitted for this kind of work… it is not the Starship Enterprise out there.

    So, maybe they did get Osama. But there is no fucking way they had any genetic proof of it by the time they dumped the body over the side. What is it that we are not supposed to see with all this distraction? I think the French call it “legerdemain”.

    Link to this

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