World Rhino Day 2013

I thought I’d do a quick update on rhinos here on Zygoma, since the theft of their horns from museum collections is something that I’ve been keeping an eye on for a while.

For the museum professionals out there it has been tough, with more thefts taking place since I published on the situation from a museum perspective at the end of 2011. On a more heartening note, there have been more arrests as well.

Of course, things have been far tougher on the rhino populations.

Poaching rates in South Africa show a steep increase since 2009, when the new wave in poaching was started after a rumour that a Vietnamese official was cured of liver cancer using powdered horn. It will be interesting to see whether the increase in poaching rate will follow the trend of the last few years, following the recent arrest of a man reputed to be one of the kingpins of the poaching and smuggling operation from South Africa.

rhino_poaching_prediction

Since the boom in poaching, rhino populations have been in decline around the world. In some cases that decline has been very rapid. In 2011 the Western Black Rhinoceros (Diceros bicornis longipes Zukowsky, 1949) was declared extinct and the Javan Rhinoceros (Rhinoceros sondaicus Desmarest, 1822) now only has one surviving subspecies, made up of maybe 40 individuals. All of this because of a single story about cancer.

As with most anecdotal claims for cancer cures (from use of vitamins to homoeopathy) there is no good evidence that rhino horn has any effect. Spontaneous remission happens and, assuming the story about the Vietnamese official contained any shred of truth there were probably numerous other treatments being used at the same time, making it impossible to identify which treatment had any effect.

If rhino horn was effective, then you might expect the countries that use it, like China, to have a lower cancer mortality rate than other parts of the world – but this is not the case. Even practitioners of Traditional Asian Medicine have explicitly stated that there is no evidence that rhino horn can cure cancer.

Moreover, if rhino horn did have any effect on a cancer, that effect should also be found by using powdered cattle hooves – a cheaper and more sustainable product. Rhino horn use is not sustainable at all. If the poaching rates continue to increase as they have been, my very quick and dirty calculations suggest that rhinos could be extinct in South Africa in as little as 10 years.

predicted_SA_rhino_decline

This is why it’s so important to raise awareness of the problems facing rhinos and communicate the fact that rhino horn is not a cure for cancer. Time is potentially very short for the populations that remain.

Friday mystery object #119 answer

On Friday I gave you this object to identify:

I asked you what this is, what it’s for, how it works and where it’s from – no easy task based on the limited information available from the photo.

Nonetheless, through a process of group deduction you worked out that it’s a copper container that holds water and produces steam and it’s from Tibet. Pretty good going. The one thing that nobody got was the purpose of this object.

Continue reading

Friday mystery object #95

It had to happen; a mystery object on Friday the 13th – a day reputed to be unlucky. So with the theme of superstition in mind I have an anthropological object for you to identify:

I admit that this doesn’t look much different to the usual mystery objects, but this one is reputed to have certain powers. Can you work out what these powers may be and where in the world this superstition comes from? Of course, the first step will be to identify what the object actually is.

As usual you can put your suggestions, observations and questions below and I’ll do my best to answer.

Good luck!

UK homeopathy awareness week

June 14th – 21st 2010 [and 2012] is the UK homeopathy awareness week, so I thought it might be a good idea to try and raise awareness of homeopathy.

Cinchona

Homeopathy is based on the principle of similia similibus curantur (likes are cured by likes). The hypothesis is that symptoms of illness are caused by a derangement of the ‘vital force‘ assumed to be present in a living organism and substances which elicit the same derangement (i.e. symptoms) will rid the body of the illness. This was originally identified in the context of homeopathy by Hahnemann with reference to cinchona bark (source of quinine) and malaria. The previous proposed mechanism of effectiveness of quinine against malaria was its bitterness, but Hahnemann sensibly identified that other bitter substances did not offer the same protection. Instead, after taking cinchona and experiencing a reaction similar to the reaction he associated with malaria, he hypothesised that it was this similarity in symptoms that made cinchona bark effective.

Modern homeopaths still use a similar method to identify their treatments. When in a healthy state they try a preparation and keep a detailed diary of any effects that they feel the treatment has on them. This is called ‘proving’ although what it is supposed to prove is hard to determine since there are no rigorous controls in place and the results are not statistically tested to see if they are anything other than random. Consider the perceived effects of taking peregrine falcon blood for example:

Short statement on peregrine falcons:

The Peregrine Falcon is widely renowned for its incredible speed. Estimates vary, but commonly cited top velocities are in the range of 290-320 km/h (180-200 mph), achieved only during the characteristic swoop (hunting dive)…the Peregrine Falcon is the fastest creature on earth.

Observation during proving:

‘Drove back from the party (had some wine but not so much) quite fast but well, changing speed as necessary. It seemed faster to the others in the car than to me.’

I heartily recommend reading the entire page about the proving of peregrine falcon blood – it is an education into how homeopaths derive their information about the treatments they prescribe (and it is ludicrous to the point of hilarity). Is this really a rigorous approach to testing healthcare products or is this more about symbolism, appeal to the mystical and delusion?

Evidence based medicine occasionally does use elements of  similia similbus curantur such as with inoculation and vaccination – where a small or denatured dose of a disease causing agent is introduced with the intent of stimulating an autoimmune response that will prevent the full blown disease from becoming established should the person come into contact with a large active dose of the pathogen.

Foxglove

Also, many physiologically active compounds have medicinal uses because they act on particular organs and metabolic pathways via a biochemical route that can have apparent similarities to the illness being treated. For example, digoxin is a cardiac glycoside found in foxgloves that decreases heart rate and increases force of heart contraction – fatal in large doses, but useful for treating atrial fibrillation in small doses – so at a very gross level this could be considered ‘like treating (rather than curing) like’. It is also vaguely plausible that a substance which elicits a physiological response which mimics symptoms of an illness that arise as part of the body’s  immune response (such as raising temperature) may have the effect of fighting an infection (although I have not seen any evidence for this).

Hahnemann’s experience with cinchona happened in 1790 when the medical community of the time was still dominated by the miasma theory and humourism of the Middle Ages. Vitalism was a standard of the medical profession at the time, with good health being dependent on balancing the four vital humours. The idea of a biochemical autoimmune system did not take shape until a century later, but when it did it revolutionised the medical field, bringing about treatments with previously unprecedented success (eradication of smallpox anyone?). Hahnemann had no idea about the mechanism by which the body actually heals itself, he also had no idea that malaria was not caused by a miasma, but by a microscopic parasitic protist of the genus Plasmodium.

Plasmodium falciparum – the protozoan that causes malaria

In short Hahnemann was trying to fit his limited observations into a theoretical framework consistent with the body of assumed knowledge available at the time. The same way that scientists have always worked. However, over time the body of knowledge has changed – vitalism has been rejected as evidence has been amassed which demonstrates that all of the functions historically proposed for vital energy are demonstrably biochemical in nature. Disease is now well recognised as being caused by bacteria, viruses, proteins and biochemical abnormalities rather than by derangement of ‘vital energy’. The idea of a vitalistic treatment for a biochemical problem seems rather at odds with the facts, particularly since there is no evidence to suggest that vital energy even exists. Sticking with malaria, we now know that the antimalarial component of cinchona is quinine, which is no longer effective as an antimalarial due to the resistance evolved by Plasmodium – how such immunity might have evolved in response to vital energy is hard to fathom.

Homeopathy also subscribes to the principle that the smaller the dose, the more effective it is at influencing the vital energy – to the point where homeopathic remedies are diluted until they no longer contain even one molecule of their active ingredient. Indeed it would take a ball of water the size of the solar system to contain one molecule of active ingredient in the more ‘potent’ homeopathic remedies – making them even less tangible than the Emperor’s new clothes. Of course this idea of smaller doses having a bigger effect flies in the face of everything that is demonstrated in evidence based medicine, where dose dependent effects increase with increasing dose size, through a therapeutic window until a plateau is reached or there is an overdose.  The Ten23 campaign was all about this misplaced faith in super-dilution.

If homeopaths were able to demonstrate that vital energy exists then homeopathy might have a theoretical leg to stand on, as would chiropractic and a suite of Ayruvedic medicines, but without any evidence for vital energy they remain theoretically unfounded. Interestingly, mainstream medicine was once based on the concept of vital energy, which has only been discarded due to improvements in experimental methods. Vital energy is one of those strange forces in nature that becomes harder to see the harder you look for it – probably because it only exists as a cultural concept that has no relevance in the physical world. This erosion of evidence for vital energy not only leaves homeopathic theory unfounded, but necessarily rejected.

Headstone for 9 month-old girl who died because her parents chose homeopathy over conventional treatments

Theory aside, if there was strong evidence for efficacy of homeopathic remedies then there would be very good reason to question the laws of physics and our current understanding of biology and medicine. However, there is no persuasive evidence for homeopathy’s efficacy. As such it seems bizarre that people still hold on to this outdated and superseded faith-based system of medicine; but then again there are still Flat EarthersFaith healers and people who drink their own pee, so I suppose it’s no great surprise. There are dangers however – if people choose to use homeopathy in place of medicines that have evidence of efficacy, they run the risk of harm or even death – and I think that’s something everyone should be aware of.

If you love homeopathy…

I was recently struck by an odd blog post “If you love homeopathy – don’t vote Liberal Democrat!

This is a post which berates Dr. Evan Harris MP for all manner of misdemeanours, not least his strong and vocal position against homeopathy. The blogger (one Sue Young) goes so far as to quote two articles from the GMC code that she feels Dr. Harris is contravening through his activities [update 14th Feb 2010 – apparently the blog post was based on a letter written by Lionel Milgrom, see Gimpy’s blog for details]. I wrote a comment relating to the fact that the overriding focus of the GMC guidelines is care to patients and it seems that Dr. Harris is fulfilling his duty to the GMC by attempting to “protect and promote the health of patients and the public” by illuminating the lack of evidence for the efficacy of homeopathy. It appears (unsurprisingly) that my comment did not make it through the comment review process, so I have posted it (and my follow-up) below.

It is not the berating of Dr. Harris that struck me as odd, nor the call to boycott the Liberal Democrats – it is the use of the term “if you love homeopathy”. This is a bit incongruous. I can understand someone loving what they do; after all I love my job, but I wouldn’t think to rely on my (admittedly irrational) fondness for dead animals as a way of motivating people to see things from my perspective. Moreover, “love” has some important connotations – not least unconditional acceptance or bias. It is here that we begin to see where the problem with homeopathy really lies.

I have said before (a couple of times) that homeopaths are believers in a 200 year old doctrine – which is why homeopathy has not changed appreciably in those two centuries. It is the inability to see past their love for their discipline that has meant that it has not been allowed to adapt and evolve. As a result homeopaths keep practicing their art with complete faith in its efficacy, despite the fact that evidence has repeatedly shown that homeopathy does not work appreciably beyond placebo (unless the studies assessing it are of low quality). Even where studies conclude that homeopathy is not effective, there are examples of homeopaths cherry-picking statements and citing them as support.

Rather like a parent is biased towards their child because of their love, homeopaths are biased towards their discipline. Evidence against the efficacy of homeopathy merely makes homeopaths feel more defensive. Logical refutation of the principles of homeopathy leads homeopaths to doubt well established facts about physics and biology rather than change their assumptions about homeopathy. It’s like a parent being confronted with video footage of their child shoplifting and responding by saying “but my child would never do that – you must be mistaken”. This is not how science works. This is certainly not how medicine should work.

Until homeopaths can put aside their love of homeopathy they simply cannot be trusted to work with the best interests of their patients in mind. Ignoring or twisting evidence to make it fit what is already believed is not beneficial. If homeopathy is ever going to be more than a dogmatic anachronism it needs to start accepting criticism and more to the point it needs to start recognising the inherent bias introduced by those that love homeopathy.

My comments:

It should be pointed out here that article 46 and 47 is not intended to defend the actions of colleagues who do not fulfil the duties of a doctor registered with the General Medical Council:

Patients must be able to trust doctors with their lives and health. To justify that trust you must show respect for human life and you must:

  • Make the care of your patient your first concern
  • Protect and promote the health of patients and the public
  • Provide a good standard of practice and care
  • Keep your professional knowledge and skills up to date
  • Recognise and work within the limits of your competence
  • Work with colleagues in the ways that best serve patients’ interests

It seems that Dr. Harris is fulfilling his duty to the GMC by attempting to “protect and promote the health of patients and the public” by illuminating the lack of evidence for the efficacy of homeopathy.

My follow up comment:

I see that you only publish comments that support your opinion. How wonderfully hypocritical in a blog about bias, but I suppose it’s only to be expected that a homeopath will cherry-pick what they want to hear.

What is science?

N.B. If you’re after a quick answer then see here, if you want an in-depth outline see here or if you want to know how science works see here– this blog is more concerned with the broader conceptual framework within which science fits.

Knowledge is an interesting concept – how can we really “know” anything? How do we determine truth from untruth? Does knowledge even require what is “known” to be true? I don’t think so – I think it merely needs to appear true.

The human brain looks for explanations – being able to identify cause and effect is a powerful capability, after all, it underpins all human achievement. For example, if our ancestors were unable to identify that seeds grow into plants, we could never have established agriculture (and subsequently civilisation).

There are a variety of ways in which we make links between cause and effect, from straightforward reflexive Pavlovian classical conditioning, through more complex methods of identifying concept-based causation, to the rigourous statistical analysis of double-blind randomised controlled trials of modern biomedical research (which marks our current best attempt at linking cause to effect, whilst minimising the influence of coincidental factors). However, one of the most common ways in which we find explanations is by relating an observed occurance with an observed outcome – we look for a correlation.

Of course, the trouble with correlations is that you will often be spotting a relationship that doesn’t really exist. Factor A might occur at the same time or increase at the same rate as factor B, but it could be due to factors 1,2 and 3. For example, seasonal sales of ice-cream in the UK can be directly correlated with seasonal umbrella sales in Australia – obviously they are not directly related to each other, but they share the factor of seasonality in their respective hemispheres. So a summer in the Northern Hemisphere sees more ice-cream being bought, whilst in the Southern Hemisphere it is winter and people are buying umbrellas to keep off the rain. This is a simple illustration that is intended to be clear, but unfortunately most of the time we find it very difficult to identify what the factors involved in a correlation actually are – but that doesn’t stop us drawing conclusions from what we see, or think we see.

Identifying cause and effect?

Identifying cause and effect?

So what else do we use as a way of acquiring knowledge Continue reading

WTF is homeopathy?

My first exposure to the word ‘Homœopathic’ was at Hampton House, a hall of residence at Bristol University which was an ex-homœopathic hospital (and is now the student medical centre). All I knew was that it was a magnificent building that used to be a hospital of some sort – but I never really thought about what the ‘Homœopathic’ bit meant – I just assumed it was another branch of medicine. Continue reading