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Except, perhaps, if it's used to develop critical thinking skills.

But I don't think that's what happened on the occasion reported under the headline Creationism taught in science class at Villa Education Trust school:

[A student who'd studied at] Mt Hobson Middle School said Darwinism was taught as an unproven theory and students were shown a video purporting to show science had found proof of God's existence.

On the 'taught as an unproven theory' bit - suffice it to say, for now, that I'd have concerns about how well the nature of science was being taught and understood in that particular classroom.

But on the video ... NewstalkZB asked me to comment on that, this morning, and so I sat down last night & watched it. (I've shared it at the bottom of this post, if you'd care to watch it too.) It's a slick little documentary, all right, but it's essentially propaganda, & I agree with Prof Easther of Auckland University: it has no place being used in a science classroom.

Why do I say this? Let me count the ways...

The video talks about 'many scientists' supporting the idea of creation, on the basis that our current understanding is that the Universe had a beginning. It does this a lot (and apparently, their reasons for doing so will shock meA). Somehow, despite this supposedly significant support, it manages to identify very few individual scientistsB. This unsupported claim reminded me of Project Steve, initiated by the NCSE in response to similar claims that lots of scientists doubt evolution. (Hint: most don't.) At least two of those cited as being examples of scientists who've seen the light turn out to be creationists (Milne & Whittaker), who made their comments back in the 50s. 

They quote Stephen Hawking as saying "It might be the greatest scientific discovery of all time," but give no other context. A search of that phrase plus Hawking's name brings up only faith-based pages repeating it. However, given that another Hawking quote is cherrypicked, I remain skeptical - particularly since he is definitely on record as saying that "physics and mathematics may tell us how the universe began" and that, "because there is a law such as gravity, the universe can and will create itself from nothing." (There's also this.)

Then there's the claim that the Universe must have been designed for human life - a claim that's later walked back to describe just our own planet. This is partly about the Goldilocks zone (as in, Baby Bear's porridge was neither too hot, nor too cold, but just right) - but it's worth noting that Mars & Venus are also within the Goldilocks zone of our star, yet neither hosts life. Thus, the fact that planets lie in this zone is not an automatic guarantee of habitability. 

And it's partly about the Anthropic Principle. The video spends quite a bit of time on that. Hawking had a bit to say about it himself (I was actually surprised that he hadn't been selectively misquoted about it for the video), and there's a really good explanation of it here, by Ethan Siegel. It's worth quoting Siegel more extensively: 

The anthropic principle simply says that we, observers, exist. And that we exist in this Universe, and therefore the Universe exists in a way that it allows observers to come into existence. ... The evidence for our existence means the Universe allows our existence, but it doesn't mean the Universe must have unfolded exactly this way. It doesn't mean our existence is mandatory. And it doesn't mean the Universe must have given rise to us exactly as we are. In other words, you cannot say "the Universe must be the way it is because we're here." That's not anthropics at all; that's a logical fallacy.

Finally, we get to the claim that there is "brilliance" [of design] in the nature of DNA. Again, there's some very misleading quoting going on, this time of Francis Crick (codiscoverer of the structure of DNA. Yes, he did say that "the origin of life appears at the moment to almost be a miracle, so many are the condistions which would have had to have been satisfied to get it going." And here's what the video doesn't tell its viewers: Crick was speaking in the 1970s, before we'd reached our current understanding of the molecular machinery that is involved in DNA replication. He subsequently admitted to having been overly pessimistic in his assumptions about the chances of abiogenesis on Earth. 

That sort of misquotation is, in my opinion, dishonest. If the only way to make a case for creationism is to shore it up with misrepresentations and half-truths, then it is hardly a case worth making. Particularly when the final section of the video, from around 20 minutes on, doesn't even pretend to be anything other than an attempt at evangelism. 

And to share it in science classes is to do the students in those classes a grave dis-service. With science and technology so important to our lives, we need people who are not only scientifically literate but skilled in thinking critically about the world. Presenting slick little pseudoscience videos in class, and misrepresenting the nature of science, is not the way to achieve that. 


A The lack of actual evidence means that my quota of shockedness = 0.

B One of those cited, Antony Flew, was not a scientist at all.


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I've always rather liked ducks, ever since we hand-reared some ducklings back when I was still a school-kid. Mind you, the innocent me of those days didn't know what I know now about the effects of sperm competition and sexual selection on their reproductive organs. (Those of an enquiring mind will learn more - much more! - in this excellent piece by Ed Yong.) I liked them enough to make mallard behaviour the focus of my Honours dissertation, before moving on to swans.


Ducks were domesticated multiple times by humans perhaps beginning around 4,000 years ago in Egypt, but dated to around 500BC in China (Zhou, Li, Cheng, Fan et al., 2018). Domestic breeds - with the exception of Muscovy ducks - are all derived from the mallard, Anas platyrhynchos. Selection by humans has given rise to quite a range of different phenotypes, with breeds differing most obviously in size and colouration. One of the most striking is the Pekin duck breed (image below), with its white feathers, very large size relative to the ancestral mallard, and its excellent rate of egg production. (Those yummy duck legs in the supermarket chiller are quite likely from Pekin ducks.) These characteristics made the Pekin duck an ideal focus for Shuisheng Hou, Yu Jiang, and their colleagues in their just-published search for the 'fingerprints' of artificial selection in domesticated waterfowl.  (However, as we'll see, their work has wider relevance.)


The paper is based on a large sequencing exercise: the team carried out whole-genome resequencingA of 40 wild mallards, 36 ducks from 12 different indigenous domesticated breeds in Southern China, and 30 Pekin ducks from three separate populations, plus another 1026 individuals produced by crossing mallards and Pekin ducks.

It seems that in China there were two phases of artificial selection during duck domestication. The first saw the development of the various indigenous domestic breeds, and the second, the specific development of Pekin ducks. There appears to have been a genetic bottleneck at the point where that breed first formed, followed by either quite a bit of genetic drift, or else artificial selection targeting those desirable white feathers and large bodies.

The researchers identified 45 'candidate divergent regions' (CDRs) on the ducks' chromosomes that appear to be related to domestication, some of which were 'markers' for various genes. For example, two CDRs were closely associated with genes involved in reproduction and nervous system activity: bear in mind that the behaviour of domesticated animals differs from that of their wild brethren.

One CDR was used to identify a gene (MITF) involved in the production of melanin. Mutations in this gene result in a loss of pigment, apparently by down-regulating the activity of all other genes downstream of it in the melanin-producing metabolic pathway. Further genomic work led the team to decide that a mutation in MITF is the underlying cause of the striking white plumage of Pekin ducks, one that would have been strongly selected for once it appeared as the down, in particular, is much valued for quilts and padded clothing.

And other CDRs appeared to be associated with a part of the genome linked to body size - traits such as the weight of various body parts & of the body as a whole. Additional genomic work traced this to a 'growth factor' gene (IGF2BP1) that's "consistently expressed in Pekin ducks but ... barely expressed in mallards" from hatching to at least 8 weeks of age. And feeding studies suggested that the Pekin duck form of IGF2BP1 affected both the feed intake of the birds and the efficiency with which they converted food to body mass, resulting in their bigger body size.

This finding has implications beyond the ducks, though: the researchers feel it's likely that

consistent postnatal expression of IGF1BPa in other animals may also enlarge their body size. Therefore, IGF2BP1 is a strong performance target for meat production ... in animals.

And from an evolutionary point of view, it's notable how quickly these genetically-controlled traits - white plumage and larger body size - became fixed by artificial selection in just over 2,500 years of duck domestication.


A This technique's also been used in a recently-published study on domestication of cattle in East Asia.


Z.Zhou, M.Li, H.Cheng, W.Fan, Z.Yuan, Q.Gao, Y.Xu, Z.Guo, Y.Zhang, J.Hu, H.Liu, D.Liu, W.Chen, Z.Zheng, Y.Jiang, Z.Wen, Y.Liu, H.Chen, M.Xie, Q.Zheng, W.Huang, W.Wang, S.Hou & Y.Jiang (2018) An intercross population study reveals genes associated with body size and plumage colour in ducks. Nature Communications. DOI: 10.1038/s41467-018-04868-4

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There's a lot of rhetoric these days around educating students 'for the 21st century', and the need for '21st century skills', while (not always but often) disparaging what is currently taught & how it's delivered. Catherine Kelsey has a good op.ed. on this on the Education Central site, in which she comments on two other opinion pieces that I - like her - had found somewhat polarising in their approaches (see here and here), and says: 

[They] are both right and both wrong: right because today we do need to ensure that we do teach the "ability to think critically, to persevere, to solve problems and relate to others" and that "great teachers improve student learning by providing a relevant and engaging curriculum ... by supporting the personal growth of each individual student". Where they are both wrong is in the suggestion that this is "new" and a shift in "paradigm"...

[G]reat teaching has always been there and has always encompassed the skills raised in both articles as well as inspiring a passion for knowledge

and delivery of those skills is particularly important: as Sun Kwok observes in his perspective article, Science education in the 21st century, "students are going into increasingly diverse careers", and not necessarily the roles traditionally expected of science graduates. His reflective paper argues for an integrated approach to teaching science, as a means to prepare students for those diverse careers (many of which may not even exist at the moment), and makes for an interesting read. 

Kwok led the Faculty of Science at the University of Hong Kong (UHK) through the implementation of some fairly significant changes in its curriculum. The intention was to give students the competencies and the flexibility to allow them to move into careers well outside those for which the traditional scientific disciplines might have prepared them: a curriculum "for the 21st century". His perspective piece is a description, an explanation, and a challenge to other institutions to reconsider their own curriculum development and delivery.

He suggests that universities "should develop students as people, prepare them to think, and set the foundation for life-long self-learning and self-improvement". However, there are barriers to this, in that

there is often a mismatch between educators' and students' expectations. Many students believe that universities will provide them with a meal ticket for a better job

and one of the challenges faced by those leading changes in tertiary curricula lies in the need to carry both current and prospective students along with them. And staff: academics can (in my experience) be somewhat suspicious of alternative methods of teaching delivery.

Kwok believes that a key problem with science education (at all levels) is that it can be seen as irrelevant to the real world. I'd have liked to see citations for the statement that students in physics & maths "feel that their discipline contents are abstract" & that they can't relate what they learn to the world outside the classroom. But I completely agree that many students fail to grasp that "the scientific method is widely applicable to different aspects of their lives". Some years ago now a colleague & I surveyed university students from a range of different year levels and were startled to find that the 3rd-years had no better understanding of the nature of science than did the 1st-years. But then, many of us do tend to assume that such understanding is gained by osmosis, rather than by explicitly teaching it. For Kwok, 

the problem is not just how much science students learn but how they connect science to their lives and society.

We need to address this, and also ensure that all students gain a set of fundamental skills - those "21st century skills" that aren't really a new paradigm at all, but essential in any time: good language/communication skills, and a set of quantitative skills that let them think about the world in a scientific wayA, regardless of what they ultimately end up doing. Research is a big part of a university academic's life, but we need to remember that perhaps the majority of our students are not going to go on to academic careers (see here and here for commentary on that); the skills we help them develop should be useful to them in a range of other professions. 

Thus Kwok believes that, despite the fact that science curricula - both in schools & at university - tend to focus on mastering factual knowledge, 

it is more important to teach the process of science, ... mastering methods such as building models, constructing experiments, taking data, revising models based on data, and communicating results. Students should acquire the ability to solve problems by studying examples of previous work. In the process, they should develop free, bold, independent, and creative thinking. 

[They should] develop their sense of curiosity and acquire the confidence to ask questions and challenge assumptions ... be knowledgable about our world and awre of how nature works ... think analytically and quantitatively, keep an open mind ... [and] be versatile enough to take on any job.

Now, I do think that, in my own Faculty & institution anyway, the curriculum changes we've instituted as a result of a university-wide review have helped us move towards this: the requirement for 'discipline foundations' papers for all degrees, for example, the expectation that all science majors will take 'numeracy' papers (in quite a broad sense of the term), our inclusion of a "Science and Mātauranga Māori paper" in the science degrees (and its equivalent in engineering), and the move from my engineering colleagues to increase the amount of experiential learning in their programs. But I think we still have a way to go, and could take a leaf out of the UHK reforms, specifically by considering the two science foundation papers introduced thereB. Why? Because the goal of these papers is

to give students a broad view of science's nature, history, fundamental concepts, methodology, and impact on civilisation and society.

and to 

[introduce] general principles and unifying concepts to describe diverse natural phenomena ... emphasising the relationships between science subjects.

The reform also includes non-discipline-based classes (I think I'd love to take his paper "Our Place in the Universe"!) that

are designed to develop broader perspectives, critical assessment of complex issues, appreciation of our and other cultures, and the qualities necessary to be a member of the global community. 

And then there's the reform of the discipline-based papers themselves, with the caveat that while we should definitely be looking at moves away from the traditional lecture format for teaching, that shouldn't overshadow changes in curriculum content and focus.

There's also something of an elephant in the room, when we talk about curriculum development. And that elephant is assessment. While we may claim to teach critical thinking, critical assessment of problems, and the ability to integrate information across the disciplinesC, unless those attributes are actually targeted by assessment as well as by teaching, nothing much is going to change. 

Kwok concludes with a plea: he hopes that

more scientists will think about how we educate our next generation. They are the people who will keep science alive.


Sun Kwok (2018) Science education in the 21st century. Nature Astronomy.


A I'd like to hope that increasing this particular competency among graduates, even non-science majors who've taken a couple of 'interest' papers in the sciences, would help to counter what seems like a rising tide of pseudoscience; the idea that science is 'just another way of knowing'.

B And some of their other innovations. I really like the idea of an induction for new first-years that includes a thorough introduction to "the differences between learning in university and in high school". 

C One of my gripes about the Achievement Standards of our NCEA system in NZ is that they do tend to result in many students being quite compartmentalised in their learning. Perhaps as a result of the pressure many teachers feel to teach 'to the assessment', many of our incoming first-years are not particularly good 'big-picture' thinkers, able to link concepts from various areas of biology. In fact, at the Schol Bio day I ran just last weekend in Hawkes Bay, some of the students commented on how different the scholarship exam is, with its emphasis on the need to integrate concepts across the curriculum, from the way they're assessed for Level 3 NCEA.


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I met with a local biology teacher today to talk about setting up a Schol Bio preparation day in the Waikato, and we also discussed things like the need for critical thinking skills (in addition to a solid base of knowledge from students' year 12 & year 13 studies and time spent in reading more widely around the subject). So here are some thoughts on this, for those of my readers thinking of entering for the examination this year.

That critical thinking needs to be applied not only to the questions themselves (just what is the examiner asking me to do? what are the key points I must answer to do this), but also to the resource material (what inferences can I draw from this? which bits of information are relevant, and to which section(s) of the question) and to your own knowledge (which of the concepts I've learned about is directly relevant here?). Assessing your own knowledge with the same care that you apply to assessing the question and determining how to integrate the resource material with your answer is very important - it'll avoid you doing what I've heard examiners characterise as a "brain dump". That's when a student simply writes down everything they know that might be related to a particular question, in the hope that some of it will be relevant. 

And then look at the construction of your answer in the same way: for example, check to see that for each statement you make, you've also written a justification. That is, why is the point you've just made, relevant? What explanation can you provide to support it?  For example, in the 2015 paper there was that question around whether the moa could possibly be brought back into our bush. In answering the part asking about factors leading to a species' extinction, you might have written that a species might be more at risk of extinction if it's a specialist (eating a fairly specialised diet). That would be an 'evidence' statement, which you'd then need to justify: if environmental conditions change so that its particular food sources become rarer, or disappear completely, then the species is less likely to survive.

Critical thinking is a learned skill, & something that needs practice. It's something your teachers will probably work on with you. But there are also resources out there that you can use. For example, has rather a good model that encourages this sort of reflection:

  • what is the question I'm trying to answer?
  • what information do I need to answer it? Of all the information available to me, which bits are relevant?
  • now I've identified all the relevant facts, what is the best possible conclusion?
  • what assumptions am I making here, and are they justified?

Teachers are probably already aware of the resource on the tki website (and the material at this link is a "heavier" extension to that.) but for a student looking for additional study pointers focused on critical thinking then this webpage is a nicely written primer on the subject. 

Don't think that these thinking & reflective skills are needed only for the exam! They're the sort of skills that you'll use throughout life - a point made by the narrator of this video :)

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Today a science-minded friend posted a screenshot of a post by another individual to the FB group 1080 eyewitness. Because it is a) heavy on the innuendo, b) inaccurate, and c) decidedly unpleasant, I thought it worthy of a bit of additional attention.

Let's look at c) first. The original poster claimed to have written this on the Prime Minister's FB page; it's a particularly nasty attempt to sow fear & confusion in womens' minds by using a combination of overstatement, innuendo, & downright inaccuracy. Jacinda Ardern is level-headed enough to ignore the item as an ill-founded rant, but I see no reason why someone should attempt to frighten others in order to push their own point of view in this way.

and, a little later

That is really is nasty.

Now b) - he implies that 1080 is a teratogen of the same order as thalidomide,

which doesn't appear to be borne out by actual scientific evidence. For example, Eason et al. (1999) state that

1080 causes developmental defects in rats when pregnant females are exposed to relatively high doses (0.33 and 0.75 mg kg(-1) day(-1)) on a daily basis during the period of organogenesis (from days 6 through to 17 of gestation). The developmental abnormalities observed were mild skeletal effects: slightly curved forelimbs, and bent or "wavy" ribs. [The birth defects caused by thalidomide are much more severe.]

These concentrations are quite high. They are also much higher than the precautionary drinking water standard defined by the Ministry of Health (2 parts per billion), and much higher than has ever been detected in water flowing from watersheds where 1080 has been dropped (0.1 parts per billion). In addition, NIWA comments that

Importantly, no 1080 has been detected in drinking water supplies.

Similarly, in 2011 Eason & his colleagues pointed out that (my emphasis)

Results of the initial research and subsequent monitoring demonstrated that there has been no evidence of 1080 presence in reticulated water and no evidence of significant or prolonged 1080 contamination in surface waters

Brown also implies that teratogens can cross the placental barrier but other chemicals can't. This is incorrect: plenty of chemicals cross the placenta. I mean, oxygen, anyone? Nutrients? But, more seriously, if 'chemicals' couldn't cross the placenta then we wouldn't see neonates affected by meth (P) or with foetal alcohol syndrome.

So, Brown is correct that 1080 is a teratogen. What he carefully ignores is that it has these effects at concentrations far higher than have ever been measured in our drinking water. That is, his implication that the PM, or anyone else drinking water supplied from the Hunua catchment, is "heavily poisoned" by 1080 is both incorrect, and blatant scaremongering.

Which pretty much addresses a) as well.

Now tea, on the other hand, does contain small but measureable quantities of sodium monofluoroacetate, aka 1080. I wonder what Brown's take on that would be?


Please note: none of this should be taken to mean that 1080 is a benign substance. It's not. But it is the best currently-available mechanism for controlling pest species in those parts of New Zealand where other methods fail. And as Eason et al. (2011) comment

There has been no evidence of significant or prolonged 1080 contamination of surface waters... The risks associated with 1080 to human health are determined by the toxicity of 1080 and the potential for exposure: risk = hazard × exposure. The innate toxicity of 1080 is not in question, as there are clearly identified lethal and sub-lethal effects as illustrated above. However, exposure risk to humans is very low with the exception of the small group of workers in the pest control industry, a group that has been closely monitored to try to ensure minimal exposure (Beasley et al. 2009).

Because of this, they state that

the use of 1080 must continue to include safeguards that focus on those individually handling 1080 or 1080 baits to ensure they do not ingest, inhale or absorb 1080.


C.T.Eason, M.Wickstrom, P.Turck & G.R.G.Wright (1999) A review of recent regulatory and environmental toxicology studies on 1080: Results and implications. New Zealand Journal of Ecology 23(2): 129-137

C.Eason, A.Miller, S.Ogilvie & A.Fairweather (2011) An updated review of the toxicology and ecotoxicology of sodium fluoroacetate (1080) in relation to its use as a pest control agent in New Zealand. New Zealand Journal of Ecology 35(1): 1-20

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I was idly skimming the Herald's website when I came across an article with the headline "Is plant medicine really that effective?" Since the article appears to be in the nature of an advertorial, the answer is, it depends on who you ask.

Unlike man-made chemical drugs that have been developed as novel medicines from the 19th century onwards, plant medicines have been used in human healthcare for millennia. 

This is what's known as an appeal to antiquity - because something's been in use for ages, it must work. It's repeated later in the article, with the claim that 

[t]raditional plant medicines have a rich history of being effectively used for over 2500 years

A rich history of being used is not the same as a history of being used "effectively". In Hippocrates’ time, for example, ‘plant medicine’ & basic surgery were about all physicians had to work with. That doesn’t mean that they necessarily achieved a high cure rate. The implication that plants are somehow better than their modern pharmaceutical counterparts is an example of another logical fallacy, the appeal to nature. (Tim Minchin was spot-on when he said “You know what they call alternative medicine that's been proved to work? - Medicine.”)

They share a long co-evolution with humans and are the foundation of their modern chemistry-based counterparts.

There are certainly many examples of coevolution involving plants and animals. However, much of this coevolution has taken the form of an arms race: as mutations that make plants less attractive to eat (e.g. spiny, less palatable, or downright poisonous) spread through a species, this can act as a selective agent on herbivores: animals with gene combinations that allow them to process the poisons are more likely to survive and spread those own genes around, and so that species evolves in turn. Coevolution does not mean, as previous articles by Clair imply (see here, for example), that plants are thus well suited by coevolution to our own needs in terms of acting as medications. The defensive alkaloids produced by many plants can certainly have a physiological impact, but as part of the plant’s anti-herbivore armoury. We can make use of some of those chemicals, sure, but natural selection didn't design them for medical (or recreational) use in any directed way. (Deliberate selection by humans is another matter.) 

But yes, many modern pharmaceutical drugs are derived from plant extracts, and pharmaocognosy is an important field of research in the search for new drugs and investigation of how traditional treatments might work. The difference being that modern pharmacology means that we can control things like dose, concentration and purity, which isn't really possible if you're using the entire plant prepared fresh each time. The chemotherapy drug taxol (isolated from the Pacific yew tree) is a good example, but there are many others, including: digitalis (foxgloves), salicin/salicylic acid (meadowsweet and willow bark), vinblastine (derived from the Madagascar periwinkle), and quinine (chinchona bark). For some drugs (e.g. vinblastine) yields from the actual plants are low, and the cost of obtaining the drug is high, so modern production methods make the drugs available to far more people than could ever avail themselves of the natural source.

... research confirms their beneficial effects for rebalancing hormones, aiding sleep, dealing with stress, in depression or strengthening the immune system. 

"Rebalancing hormones" seems to be one of those 'catch-all' phrases - which hormones are we talking about, & why do they need "rebalancing"? How did they get out of whack in the first place? Similarly, "strengthening the immune system": it's a meaningless term and ignores the fact that in the great majority of people the immune system works just fine. Other than the use of vaccines, "strengthening" or "boosting" may not be such a good idea... And in some instances evidence for other uses is conflicting.

Plant medicine can provide you with essential building blocks for organ health that cannot be found through diet alone, and have a cumulative effect on the body to help build or restore your physiology to the optimal levels.

Sorry, what? Which 'building blocks' would those be? All the building blocks of life – amino acids, di- & monosaccharide sugars, fatty acids, nucleotides, vitamins & minerals – are provided in an average diet. So what are these things that diet supposedly doesn't deliver?

In fact, Western biomedicine is historically rooted in plant medicine, given that it was the main form of medicine until the establishment of the new economic order after the industrial revolution.

And why did medical practices change at that point? Perhaps, because it became much easier to identify the actual active ingredients, and produce standardised doses of known concentrations and purity? Perhaps because the ability to do this meant that some drugs, at least, could become more widely available? Certainly the use of lab-made ingredients would help to protect species such as the Madagascar periwinkle, or plants such as goldenseal & ginseng, which in the US anyway have become endangered in parts of their range due to overharvesting for 'traditional' uses. 

Since the mid-1980s there has been an explosion of research into complementary and alternative medicines (CAMs), driven by consumer demand for natural medicines. There have been over 40,000 studies conducted over the past three decades. This means that in addition to traditional empirical evidence, we have increasing evidence based on newer methodologiesA such as randomised controlled trials. They overwhelmingly confirm traditional medical applications of plants.

Some citations would be nice. This would enable us to answer questions such as: of these 40,000 studies, how many were randomised controlled trials (RCTs)B? How many of those were properly blinded? Were they in vitro studies, carried out in petri dish or test tube, or in vivo, using animal models? Were they studies based on whole plants, or on extracts thereof? And – what were their results? 

Traditionally, plant medicine incorporates the whole plant and its extracts, and with this it brings a full spectrum of active constituents that work synergistically on different parts of the body's physiological functions. 

There are certainly examples where different plant constituents can act in a synergistic manner. One such example, looking at antibacterial activity in extracts of the plant goldenseal, is discussed here. It identified the actual compounds, their structure, and their likely modes of actionC. (What’s not to like?) Notably, while the goldenseal article was written in 2011, evidence that the same action occurs in vivo is (as far as I could tell from a quick pubmed search) still lacking. It’s also worth pointing out – should this evidence eventuate – that a synthetic preparation of the 3 compounds would be a much more reliable source than a tisane or a poultice of the whole plant.

Plant medicines will only work if they have been expertly compounded – from harvesting the plant at the right time at their peak potency, to careful processing them to preserve their active constituents and then to the correct formulation.This means to reap the many benefits of plant medicine, you must ensure you are getting them form [sic] a trusted company or registered Medical Herbalist.

And thence, my comment on advertorials.


A The idea of RCTs isn’t actually a modern invention. Perhaps the first such trial (albeit an imperfect one) was run by James Lind, back in 1747, in seeking a treatment for scurvy. He subsequently followed this up with a systematic review of the subject.

B There are some good explanations & examples in terms of trial design at this link.

C Thus the statement in a 2015 op.ed by the same writer, that “we simply do not have the technology yet to understand exactly how they work”, is incorrect. (Nor, from that same article, is it accurate to say that there are no side-effects if you use a whole plant remedy: see here, here, & here, for example.)



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I subscribe to the Tertiary Insight newsletter (a great way to keep up with news of what's happening in the tertiary sector). Yesterday's edition  included a statement (& a link) about the NZQA's decision to cancel the registration of the Aromaflex Academy. It seems that this Private Training Establishment (PTE) was placed under strict conditions in January 2018, & has presumably failed to meet them. 

Now, if you go to the Academy's webpage, you'll see that it offers courses about "The Science of Aromatherapy, Reflexology, Holistic Massage, Anatomy & Physiology". Personally, I struggle to see how one could offer a course in the science of either aromatherapy or rellexology (of which, more at the end of this post), so my first thought was that the NZQA's decision was - from a scientific perspective - a Good Thing. However, the list of compliance requirements shows that they are regulatory in nature, and in fact this is how the NZQA processes are intended to work.

And so they should: we absolutely need to ensure that providers comply with the various regulations that ensure the quality of the learning experiences for students and the quality of the outcomes that they attain. But surely we should also be asking questions about whether the nature of what's taught in programs describing themselves as science-focused - the actual content side of the curriculum - is evidence-based as well?

In this particular case, the Academy's website lists a number of offerings. From a science perspective the anatomy & physiology certificate sounds OK (although without access to the study materials it's hard to say more than that). As currently described on the website

The Anatomy & Physiology award is the 'foundation' upon which all other Complementary, Beauty and Sports Therapy awards are based. It is comprised of 12 units encompassing all systems of the body: The Chemistry of Life & Pathology, Cells, Tissues and the Skin, Skeletal System, Muscular System, Nervous System, Human Senses, Endocrine System, Circulatory System, Lymphatic and Immune System, the Respiratory System, the Digestive System and the Urinary & Reproductive Systems.

However, I'm puzzled about how someone with an even an introductory understanding of those body systems and their functioning (it's described as a level 4 Certificate) could then go on to accept the idea of reflexology. Again from the website

The Diploma in Reflexology qualification is a study of the reflexes of the feet that relates to the various parts of the body. Hand Reflexology and Auricular Therapy (reflexes of the ears) are also taught over the various block week courses.  Students also learn about Zone Therapy and the Meridians relating back to the feet and hands.  

This statement appears to be using the word 'reflexes' in a rather non-scientific way; here's a definition that someone who's learned about the nervous system should be familiar with. In addition, since the 'meridians' relating to feet, ears & hands seem to be totally invisible to science (ie non-existent), it's hard to see how a course could reasonably claim to teach the science underlying them. Which leads to the next question: is that aspect of delivery something that NZQA considers in approving programs & papers? And if not, should that change?

The scientists & doctors at Science-Based Medicine have written quite a lot about reflexology and the fairly specific specific health claims made by some providers, They note that a 2011 systematic review found that there is no convincing evidence that relexology is effective against any medical condition. (The massage aspect of it may well make you feel better, in a general sense, but that's a different issue.)

It's the same for aromatherapy: nice fragrances can be relaxing, but as Steven Novella comments, "high quality studies are almost completely lacking in the published literature regarding essential oils." He goes on to explain that any studies demonstrating efficacy need 

to be properly blinded and adequate controls are essential. You can use pseudo-objective measures, like the need for additional pain medication, functional ratings, and other markers of their health outcome as appropriate. And of course, studies need to be large enough and carried out for long enough to get adequate data, and executed to prevent p-hacking.

Especially when dealing with a treatment for a subjective symptom like pain, one that we know to be highly modifiable by non-specific interventions (like distraction, mood, the introduction of a novel treatment, physical contact, the environment, interaction with the practitioner, and other variables), adequate controls are essential (pun intended).

Now, I understand that people believe in these modalities, regardless of whether or not there's empirical evidence that they work, and that the NZQA

approves training schemes if they are genuinely needed by learners and stakeholders,

but is that sufficient grounds for accrediting courses that claim to teach 'the science of...' but from a scientific perspective appear to be a combination of massage and magical thinking?


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I'm starting to gear up for some Schol Bio preparation days in the regions (hi, Hawkes Bay! See you in 4 weeks!) and realised that I haven't written anything specifically focused on those exams for a while. So I thought that putting something together would be a good way to spend a rather wet Sunday. At these days we usually put quite a bit of time into working on answers to the previous year's questions, so in this post let's look at one from the 2015 paper.

In 2015, the examiner based question #1 on a statement by then-Opposition MP Trevor Mallard that he felt that it could be possible to bring moa back to our national parks

... the moa will be a goer, but we're talking 50-100 years out

and expressed a desire to see

small ones that "don't weigh much more than turkeysA ... ones that I could pat on the head rather than ones that are going to bowl us over...

After providing some other contextual material (as is the norm for Scholarship Biology - be aware that you'll need to factor a reasonable amount of reading time into your planning on the day), the examiner asked students to

Analyse the information provided in the resource material and integrate it with your biological knowledgeB to discuss:

  • the evolutionary and ecological factors that contribute to declining population numbers that may result in the extinction of species AND account for the very large increase in the rate of extinction of species in modern times. Use named examples to support your discussion
  • how humans could manipulate the transfer of moa DNA to restore a moa population to the Rimutaka Forest Park AND analyse the biological implications of this. Give your justified opinion on whether the 'moa is a goer'.

There are a number of factors that could feed into a decline in population size. High on most lists would be a reduction in the genetic diversity of the population, something that could be due to genetic drift. If the population is isolated, there would be little or no gene flow due to migration or breeding with individuals from other populations, which would also have a negative impact on genetic diversity and result in the phenomenon of inbreeding depression. (Think of NZ's black robins, as an extreme example.) This is why those managing endangered species such as takahe & kakapo are careful to mix breeding up where possible.

Then, if a species is a specialist, environmental change could pose a problem if the resources the organisms rely on diminish or disappear; they may lack the flexibility to change to others. Specialists are then perhaps more likely to feel the effects of loss of habitat due to climate change or a natural disaster; if they're a non-migratory species then the problem is compounded. Either way, the population sizes of such species are likely to decline. That environmental change can include the arrival of exotic predators, competitors, & diseases - something that's certainly had a significant negative effect on NZ's native fauna & flora. Takahe, for example, have suffered from competition with deer, but were also badly affected by the arrival of stoats. Mustelids, rats, & feral cats kill native birds, reptiles, and insects much faster than the prey species can replace their losses. And chytrid fungus infections pose a threat to amphibian species worldwide, including our own ancient native frogs.

Ultimately their population size may become too small to be sustainable - this is where the concept of 'effective population size' comes into play. If the total size is large, but most individuals are past their normal breeding age, then the effective population size is small. This means that at the population level, reproductive outputs decline. And once death rate exceeds the birth rate, extinction is on the horizon. In addition, in a small, isolated population inbreeding becomes common, and any harmful recessive alleles may be more likely to be expressed. 

It may not be only that species that's affected, either. Removal of one species from an ecosystem can have ramifications for the entire ecosystem - this relates to the concept of a keystone species.

In all of this, we should not forget or underestimate the impact of our own species. Habitat destruction accompanies human settlement, as does the introduction of new species (in NZ, rabbits, possums and pigs along with the deer, rats, cats, dogs, and mustelids). Humans are reasonably efficient predators themselves: it's estimated that moa became extinct here within 200 years of first human arrival. (Research suggests that human arrival & expansion, coupled with climate change, is implicated in megafaunal extinction in Patagonia & elsewhere.)

So, could we bring 'the moa' back? (I really dislike this whole 'the' thing: there were around a dozen different species of moa in NZ, with their own ecological niches.) In theory, yes, we could. It's possible to extract DNA from moa bones, and Massey University researchers used this aDNA to work out how many species of moa once existed here. Mind you, to bring any species of moa back you'd need to ensure you had its full genome!

Then, you'd need to identify a suitable surrogate parent, remove the nuclear DNA from eggs from that host, replace it with your moa DNA, and implant the egg into the surrogate. What would that surrogate be? Perhaps another ratite, such as an emu? Or - if we're going with Mr Mallard's wish for small & manageable moa - perhaps a turkey, given the similarities in size. You'd need to do this multiple times, with the remains of multiple individuals of your target species, and to clone both male and female moa (using the sex chromosomes to identify them), in order to end up with a genetically-variable breeding population. 

Easy to say. But in reality things are likely to be more complex, & more difficult, than that. It's debatable, for example, whether scientists could find a large enough number of P.geranoides individuals to be able to reconstitute that genetically-variable population. In that case, the threats related to inbreeding & genetic drift would still be there, and the species could well spiral back into extinction. 

From an ecological perspective, moa were reasonably large, and each individual would eat a lot of vegetation each day. Given that the Rimutaka Forest probably isn't the same as it was when moa were in their hey-day, would re-introducing moa have a negative effect on the current ecosystem, particularly on the other herbivores? We need to be able to answer that one, to avoid inadvertently causing further changes to the forest community's species composition. 

So, what would be your final opinion? You could argue, along with Mr Mallard, that yes, "the moa is a goer". Remember that you need to justify that opinion: bringing moa species back could help to re-establish the natural biodiversity of ecosystems that human actions have damaged.

Or, you could say - as I would - that no, this isn't a viable proposal. Firstly, as far as I'm aware, birds have yet to be cloned successfully. (There's a list of cloned species, plus a lot more information, at this FDA link.) And secondly, this seems to be a diversion from a more pressing problem: the need to use that money & scientific effort to conserve those ecosystems and species that we currently have.


A Mr Mallard was wise to limit the size of the species he wanted resurrected. After all, the giant moa species, Dinornis robustus & D.novaezelandiae, stood over 2m tall & weighed around 250kg. The much smaller Mantell's moa, Pachyornis geranoides, was under 0.5m tall & would have tipped the scales at 20kg ie roughly turkey-sized. Much less alarming, should you meet one in the bush!

B This reminds me that I also need to write something on what the examiner is looking for, in giving an instruction like this.

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Over the last few years, OracA has written quite a bit about the so-called 'right to try' legislation that has been enacted in many US states - and, as this post of his describes, will now most likely become a thing at the federal level. (I say "most likely", given President Trump's history of wanting to significantly reduce FDA regulations and his support of 'right to try'.) Orac describes the legislation as a 'cruel sham', and if you read the post I've linked to, you'll see why. Basically, under this legislation a drug need have no evidence of safety or efficacy to be a 'right to try' medication; only evidence that it's not dangerously toxic. In addition, patients have no come-back if such a drug should make them sicker, do permanent harm, or be a cause of death. Nor can the Federal Drug Administration use any such negative results in making a decision to allow its use in the healthcare sector without having to justify this to the relevant Secretary. As Orac says, this last is totally backwards: "In other words, the burden of proof is on the FDA, not the company seeking approval for its drug, as to why right-to-try outcomes should be included." And it's likely that this 'right' would be available only to those who can afford it or are particularly effective fund-raisers. Certainly sounds pretty cruel to me.

After commenting that

Right-to-try was, is, and has only been very little about actually helping patients. Rather, it’s always been far more about dismantling the FDA and giving drug and device manufacturers more freedom to market drugs and devices with much less testing than it has been about helping patients

Orac concludes by saying that he fears that the outcome of this bill becoming law will 

leave the FDA in a state so weakened that a new age of snake oil will be ushered in under the delusion that the free market will guarantee drug safety.

It will almost certainly make it easier for the purveyors of pseudoscientific 'treatments' to make money off the suffering and fears of desperate people. (More money than they already do.)

And it makes me wonder, why do we seem so unable to remember the lessons of history? After all, there is a reason for the existence of the FDA. The recent book Quackery: a Brief History of the Worst Ways to Cure Everything (Kang & Pedersen, 2017) amply demonstrates why the US first implemented the Pure Food & Drug Act in 1906, & subsequently transformed the relevant watchdog organisation into the Food & Drug Administration in 1930. The FDA hasn't eliminated quackery, but certainly plays a sigificant role in reducing its reach. I found this particular book both informative and shocking. (It also includes a little too much 'cutesy' phrasing for my taste, but that is probably just me.)

America (probably in company with many other countries) had a real problem with 'patent medicines' back in the 19th and early 20th centuries, when the free market very definitely did little to guarantee drug safety. Labels and advertisements that were false &.or misleading beguiled consumers into buying all sorts of nonsense; food often contained unsafe ingredients; and both foods and medicines were adulterated. Take the radium craze, for example. Products containing radium were sold for all sorts of supposed health issues - including radium suppositories to cure 'sexual indifference' in women! Or you could buy a combination of 'animal glands' tablets (possibly containing testicular material...) and radium supplements that would help "weak discouraged men bubble over with joyous vitality" (Kang & Petersen, 2017) Kang & Pedersen describe the case of wealthy industrialist Eben Byers, who routinely drank several bottles of the patent radium-containing medicine Radithor every day, convinced it was good for his health.

When he died in 1932, having drunk 1500 bottles of the stuff over a five-year period, the once strong & vigorous Byers weighed just 42kg. His kidneys had failed, his brain was abscessed, the bones of his skull were eroded and pitted with holes, and in an attempt to stop cancer spreading surgeons had removed most of his jaw. His bones were so radioactive that he was buried in a lead-lined coffin. 

This high-profile death was followed by swift FDA action to remove Radithor from the market and block further production. As the authors note, this doesn't mean radium doesn't have legitimate medical uses, because of course it did and still does, in the treatment of some cancers. But this use is highly regulated and has science to back it. 

Quackery includes a host of other examples: strychnine (as a 'supplement' for marathon runners and in the Victorian equivalent of energy drinks - and in "JEMS - Nature Engergiser Pep Tablets", touted to "Married Men & Women" to help them enjoy life, especially night life); tobacco (promoted in a totally innocently non-ironic way back in the 1570s as a cure for cancer); and enemas & colonic irrigation as a means to 'detox' - sadly, these last 'treatments' remain a mainstay of cancer treatments such as the Gonzales protocol. It's an alarmingly long list. Many of the offerings examined by Kang & Pedersen claim to cure cancer, & it's here that the 'right to try' legislation will probably have its first real impact. After all, a cancer diagnosis is a scary thing in itself, & hearing the word 'terminal' associated with it can be terrifying. In similar vein to Orac, Kang & Pedersen comment that

There will always be quacks out there ready to take full advantage of human desperation before science and medicine can find solid solutions.

There will indeed; see here, here, & here. Obviously the FDA isn't perfect: these examples exist despite that organisation, which came into being to help protect consumers, and similar regulatory bodies elsewhere. And as Orac points out, this new US legislation will only make it easier for them, and others, to thrive there.


A Orac's actual identity is pretty much an open secret to those who regularly read his blog.


L.Kang & N.Pedersen (2017) Quackery: a Brief History of the Worst Ways to Cure Everything. Kindle edition, ASIN: B06XDX2X15

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A couple of days ago I had a chat with a journalist that resulted in my being quoted - along with Dr Shaun Holt - in this story about purveyors of Kangen water. If you believe the hype, this stuff cures a wide range of ailments & leaves you bright-eyed & bushy-tailed. IF... but sadly, these days personal anecdote seems to count for more than that nasty stuff called evidence, and so many do believe the hype.

The Whanganui Chronicle quotes someone selling Kangen water machines (for $4,000A a pop!) as follows:

"I'd go through two 2.25 litres bottles of Coke every day. That was my normal diet."

Then a cousin in Raetihi told her to try Kangen water and she was hooked straight away.

"I feel a lot more alert - it's given me more of a zing within my body."

Yes, well, as Mark Hanna (who blogs on Honest Universe) commented on Twitter,

The Chronicle comments that the manufacturers of these machines provide fliers that make various claims: that the water they produce has proven therapeutic benefits for "more than 150 diseases including cancer, diabetes and cardiovascular disease". (Seems to me that making therapeutic claims might be stretching the boundaries of the Medicines Act...) And they claim that the water has these effects because

it restore[s] the drinker's body to a more alkaline state. 

Now, the problem with that particular claim (based, ultimately, on misunderstanding &/or misinterpretationB of Otto Warburg's work on tumour metabolism) is that your stomach operates at a low (very acidic) pH. Quaff a glass of alkaline water? It'll likely be neutralised when it hits your stomach. In addition, your body's lungs & kidneys maintain tissue pH within a very narrow range; excess hydrogen (H+) or hydroxyl (OH-) ions are excreted in urine, but the tissue pH remains pretty much constant. So those glasses of expensive H2O will keep you nicely hydrated (& feeling good), but they won't be doing much else, & certainly not making changes to your body's tissue pH, though there may be temporary changes in the urine.

Wikipedia has a good article on how these machines actually work. Basically, they are electrolysing tap water as it passes through them. However:

The effectiveness of the process is debatable because electrolysis requires significant amounts of time and power; hence, the amount of hydroxide that could be generated in a fast moving stream of water such as a running tap would be minimal at best.

They're also highly unlikely to produce 'hexagonal water' (despite claims from head office, that one is chemical quackery), or significantly affect the oxygenation status of your tap water (another claim about the Kangen machines). Plus, as Ben Goldacre once commented (in a different context), you don't have gills in your gut.

Honestly, there are so many resources out there that assess the claims for alkaline water - and find them wanting - anyone considering buying one of these things would find it easy to some due diligence first. (You could start with Skeptoid's explanation, or follow some of the links I've provided.) Then, hopefully, you'll put the $4K back in your bank account, and drink a nice glass of chilled tap water. 


A I venture to suggest that once you've bought a machine, there's a significant incentive to keep pushing the product regardless.

B One R.O.Young made a lot of money on the back of pushing that one.

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