The vertical limit for randomised trials

Alison Campbell considers the evidence for the efficacy of parachutes.

Recently a teacher sent me a paper titled: ‘Parachute use to prevent death and major trauma related to gravitational challenge: systematic review of randomised controlled trials‘ (Smith and Pell, 2003, BMJ 327: 1459-1460). I have to say I chuckled when I read this – a common charge levelled against current medical practice by the alternative health lobby is that many medical techniques haven’t been subjected to randomised controlled trials (with the corollary that it’s thus unfair to demand evidence from such trials on alternative practices).

The authors state they conducted a literature search of some of the major science sources, using the search words ‘parachute’ and ‘trial’. However (and unsurprisingly), they found no randomised controlled trials (RCTs) of parachute use. Smith and Pell begin their discussion with the following inspired statement:

“It is a truth universally acknowledged that a medical intervention justified by observational data must be in want of verification through a randomised controlled trial.”

Many medical interventions probably fall into this category – for example, I doubt that surgery for severe appendicitis has ever been subjected to such a trial. That’s not to say that, where appropriate (and in the case of appendicitis it almost certainly isn’t!) such trials shouldn’t be performed. As Smith and Pell point out, hormone therapy for post-menopausal women seemed – on the basis of observational studies – to convey a number of health benefits. But RCTs showed that hormone replacement therapy actually increased the risk of ischaemic heart disease.

As the authors say, RCTs avoid a major weakness of observational studies: that of bias (eg selection bias and reporting bias). They note that individuals jumping from aircraft without the help of a parachute are likely to have a high prevalence of pre-existing psychiatric morbidity (ie they are probably not in their right minds when they jump. You have got to love this paper!). So any study of parachute use could well be subject to selection bias, in that those using them are likely to have fewer psychiatric problems than those who don’t. Smith and Pell also put forward the possibility that enforced parachute use is simply a case of mass medicalisation of the population by out-of-control doctors – or worse, by evil multinational corporations. (These are, of course, charges frequently levelled at the medical world, eg by those who are against interventions such as vaccination.)

This little gem of a paper contains some valuable lessons on the nature of science (and more particularly, science-based medicine). And it should be read by anyone who doubts that scientists have both creativity and a good sense of humour.

An alien star-child?

Waikato University biological sciences lecturer Alison Campbell posts a regular blog on matters biological (sci.waikato.ac.nz/bioblog/). Her aim is to encourage critical thinking among secondary students. We think these need sharing.

Last week one of my students wrote to me about something they’d seen on TV:

My friend and I saw this on Breakfast this morning. Although we don’t think it is all true, we are still interested because they talked a lot about the skull’s morphology and how they believe it is the offspring from a female human and an alien. Here’s the website on it: www.starchildproject.com

It would be great to hear your thoughts.”

So I went off and had a look at the website, and wrote back. My first thought is that (following what’s called ‘Occam’s razor’) the simplest possible explanation is likely to be correct, ie that this is simply a ‘pathological’ human skull, rather than a mysterious alien-human hybrid. (Read Armand LeRoy’s book Mutants to get a feel for just how wide the range of potential variation is in humans.)

Happily there are ways of testing this – the skull is reportedly only 900 years old so it should be possible to look at its DNA.

And indeed this has been done – and the data are presented on the Starchild project’s website. Which surprised me more than a little, given that they don’t support the hybrid idea! The skull in question – which certainly has an interesting shape – was found along with the remains of an adult female. The DNA results show that both woman and child were native Americans, not related to each other, and also that the child was male. There is absolutely no indication there of any ‘alien’ DNA. Which is what I would have predicted – if we were to be visited by extraterrestrial individuals, why would we expect them to be a) humanoid and b) genetically compatible with us? ie the likelihood of successful interbreeding is vanishingly small. And that’s a big ‘if’ in any case … Carl Sagan had some sensible things to say on that issue in The Demon-haunted World.

My personal view is that the whole thing should have been examined rather more critically by the programmers before it made it to air. But then, I have ceased to be surprised at the uncritical nature of much that’s presented by our broadcast media (with the honourable exception of the National Programme!).

Science as a human endeavour

If students are to pursue careers in science, they need to be able to see themselves in that role. One way to encourage this may be through the telling of stories. This article is based on a presentation to the 2008 NZ Skeptics Conference in Hamilton.

New Zealand’s new science curriculum asks us to develop students’ ability to think critically. As a science educator I think that’s about the most important skill we can give them: the ability to assess the huge amount of information that’s put in front of them from all sorts of sources. We also need to recognise that the ideas and processes students are hearing about have come to us through the activities of people – it’s people who develop science understanding. Science changes over time, as people’s ideas change. It’s fluid, it’s done by people, and it’s a human endeavour.

This puts science in an interesting position. It has its own norms, and its own culture, but it’s embedded in the wider culture as well. Those norms of science include its history. I find it sad that many of my students have no idea of where the big ideas in science came from. They don’t know what the people who were developing those ideas were like.

The new curriculum document recognises that the nature of science is an important strand in the curriculum, because it is what gives science its context, and lets students see science as a human endeavour. They’re going to learn what science is, and how scientists do science. They will become acquainted with the idea that scientists’ ideas change as they’re given new information; that science is valuable for society. And students are going to learn how it’s communicated.

Our future prosperity depends on students continuing to enter careers in the sciences. Richard Meylan, a senior adviser at the Ministry of Research, Science and Technology, said to me recently that somewhere between the end of year 13 and that two-month break before they go to university, we seem to be losing them. The universities are tending to see a drop in the number of students who have picked science as something that they want to continue in. Students don’t seem to see it as a viable career option, and there are many reasons for that.

We need more scientists, we need scientifically-literate politicians, and we need a community that understands science: how science is done, how science is relevant; one that sees science and scientists as being an integral part of the community. But how are we going to get there? What sorts of things can we do that are going to make young people want to carry on in science? Students often don’t choose science – how are we going to change that?

One of the reasons, perhaps, is that they often don’t see themselves as scientists. We did a bit of research on this at Waikato University last year, asking what would encourage our first-year students to continue as scientists. And what they were saying was, “Well, a lot of the time I don’t see myself as a scientist.” We asked, what would make a difference? The response: “Seeing that my lecturers are people.” People first, scientists second.

When I googled ‘scientist’ I had to go through eight or nine pages of results before finding something that looks like my own idea of a scientist. (‘Woman scientist’ is a bit better!) Almost all the guys have moustaches, they’ve all got glasses, all the women are square-shaped. Students don’t see themselves in this. We need them (and the rest of the community!) to see science as something that ordinary people do.

Now, what sorts of things are those ordinary people doing? They’re thinking; they’re speculating, they’re saying ‘what if?’ They’re thinking creatively: science is a creative process and at its best involves imagination and creativity. Scientists make mistakes! Most of the time we’re wrong but that doesn’t make good journal articles; usually no-one publishes negative results. So you just hear about the ‘correct’ stuff. Scientists persist when challenged, when things aren’t always working well.

Science stories

One way of fostering students’ engagement with science, and seeing themselves in it, is to tell them stories, to give them a feeling of how science operates. Brian Greene, a science communicator and physicist in the US, says:

I view science as one of the most dramatic narratives our species can tell. The story of our search to understand the Universe and ourselves. When that search is conveyed using the power of story – the story of discovery – we can all feel part of the journey.

So I’m going to tell you stories. And I’m going to tell stories about old, largely dead, people because one of my passions at the moment is the history of science. A lot of science’s big ideas have a history that stretches back 3-400 years. But they’re just as important today, and I think that an understanding of the scientists who came up with those ideas is also important today.

I think it’s important that kids recognise that a lot of scientists are a bit quirky. But then, everyone’s a bit quirky – we’re all different. One example of someone ‘a bit different’ is Richard Feynman. Famous for his discoveries in the nanotech field, he was a polymath: a brilliant scientist with interests in a whole range of areas – biology, art, anthropology, lock-picking, bongo-drumming. He was into everything. He also had a very quirky sense of humour. He was a brilliant scientist and a gifted teacher, and he showed that from an early age. His sister Joan has a story about when she was three, and Feynman was nine or so. He’d been reading a bit of psychology and knew about conditioning, so he’d say to Joan: “Here’s a sum: 2 plus 1 more makes what?” And she’s bouncing up and down with excitement. If she got the answer right, he’d give her a treat. The Feynman children weren’t allowed lollies for treats, so he let her pull his hair till it hurt (or, at least, he behaved as if it did!), and that was her reward for getting her sums right.

Making mistakes

We get it wrong a lot of the time. Even the people we hold up as these amazing icons – they get it wrong. Galileo thought the tides were caused by the Earth’s movement. At the time, no-one had developed the concept of gravity. How could something as far away as the Moon possibly affect the Earth? We look back at people in the past and we think, how could they be so thick? But,in the context of their time, what they were doing was perfectly reasonable.

Louis Pasteur, the ‘father of microbiology’, held things up for years by insisting that fermentation was due to some ‘vital process’ it wasn’t chemical. He got it wrong.

And one of my personal heroes, Charles Darwin, got it completely wrong about how inheritance worked. He was convinced that inheritance worked by blending. When Darwin published The Origin of Species, in 1859, Mendel’ s work on inheritance hadn’ t been published. It was published in Darwin’s lifetime – Mendel’s ideas would have made a huge difference to Darwin’s understanding of how inheritance worked – part of the mechanism for evolution that he didn’t have. But he never read Mendel’s paper.

Scientists do come into conflict with various aspects of society. Galileo had huge issues with the Church. He laid out his understanding of what Copernicus had already said: the Universe was not geocentric, it didn’t go round the Earth. The Church model was that the Universe was very strongly geocentric: everything went round us. Galileo was accused of heresy, and shown the various instruments of torture; for pulling out his thumbnails and squashing his feet. He did recant, and he was kept under house arrest until his death. And the Church officially apologised to him in 1992. A long-running conflict indeed.

And there’s conflict with prevailing cultural expectations. Beatrice Tinsley was an absolutely amazing woman; a New Zealander who has been called a world leader in modern cosmology, and one of the most creative and significant theoreticians in modern astronomy. She went to the US to do her PhD in 1964, and finished it in 1966. Beatrice published extensively, and received international awards, but she found the deck stacked against her at the University of Texas, where she worked. She was asked if she’d design and set up a new astronomy department, which she did. The university duly opened applications for the new Head of Department. Beatrice applied. They didn’t even respond to her letter. So she left Texas. (Yale did appreciate her, and appointed her Professor of Astronomy.) A couple of years later she found she had a malignant melanoma, and was dead by the age of 42. The issue for Beatrice was a conflict between societal expectations and the area where she was working: women didn’t do physics.

Science versus societal ‘knowledge’

Raymond Dart was an English zoologist who worked at the University of Witwatersrand in South Africa. He was widely known among the locals for his fondness for fossils; you could trundle down to Prof Dart’s house, bring him a lovely bit of bone, and he’d pay you quite well. One day in 1924 the workers at Taung quarry found a beautiful little skull – a face, a lower jaw, and a cast of the brain – in real life it would sit in the palm of your hand. Dart was getting ready for a wedding when the quarry workers arrived, and he was so excited by this find that when his wife came in to drag him off to be best man, he still didn’t have his cuffs and his collar on and there was dust all over his good black clothes. He was absolutely rapt.

Dart looked at this fossil and saw in it something of ourselves. He saw it as an early human ancestor. The jaw is like ours, it has a parabolic shape, and the face is more vertical -relatively speaking – than in an ape. He described it, under the name Australopithecus africanus, as being in our own lineage and went off to a major scientific meeting, expecting a certain amount of interest in what he’d discovered. What he got was a fair bit of doubt, and some ridicule. How could he be so foolish? It was surely an ape.

By 1924 evolution was pretty much an accepted fact in the scientific community. But there was a particular model of what that meant. In some ways this built on the earlier, non-evolutionary concept of the Great Chain of Being. They also had a model that tended to view the epitome of evolutionary progress as white European males. It followed from this that humans had evolved in Europe, because that’s where all the ‘best’ people came from. Black Africans were sometimes placed as a separate species, and were regarded as being lower down the chain.

Yet here was Dart saying he’d found a human ancestor in Africa. This would mean the ancestor must have been black – which didn’t fit that world-view. It’s a racist view, but that reflected the general attitudes of society at the time, and the scientists proposing that view were embedded in that society just as much as we are embedded in ours today.

Another difficulty for Dart had to do with prevailing ideas about how humans had evolved. By the 1920s Neanderthal man was quite well known. Neanderthals have the biggest brains of all the human lineage – a much bigger brain than we have. And the perception was that one of the features that defined humans, apart from tool use, was a big brain. It followed from this that the big brain had evolved quite early. Dart was saying that Australopithecus was a hominin, but Australopithecus as an adult would have had a brain size of around 400cc. We have a brain size of around 1400cc. Australopithecus didn’t fit the prevailing paradigm. The big brain had to come first; everybody knew that.

And belief in that particular paradigm – accepted by scientists and non-scientists alike – helps to explain why something like Piltdown man lasted so long. Over the period 1911-1915 an English solicitor, Charles Dawson, ‘discovered’ the remains of what appeared to be a very early human indeed in a quarry at Piltdown. There were tools (including a bone ‘cricket bat’), a skull cap, and a lower jaw, which looked very old. The bones were quite thick, and heavily stained. This was seized upon with joy by at least some anatomists because the remains fitted in with that prevailing model: old bones of a big-brained human ancestor.

People began to express doubts about this fossil quite early on, and these doubts grew as more hominin remains were confirmed in Africa and Asia. But it wasn’t completely unmasked as a fake until the early 1950s. The skull looked modern because it was a modern (well, mediaeval) skull that had been stained to make it look really old. The jaw was that of an orangutan, with the teeth filed so that they looked more human and the jaw articulation and symphysis (the join between right and left halves) missing. When people saw these remains in the light of new knowledge, they probably thought, how could I have been so thick? But in 1914 Piltdown fitted with the prevailing model; no-one expected it to look otherwise. And I would point out that it was scientists who ultimately exposed the fraud. And scientists who re-wrote the books accordingly.

Thinking creatively

The next story is about Barry Marshall, Robin Warren, and the Nobel Prize they received in 2005. (These guys aren’t dead yet!) Here’s the citation:

[The 2005] Nobel Prize in Physiology or Medicine goes to Barry Marshall and Robin Warren, who with tenacity and a prepared mind challenged prevailing dogmas. By using technologies generally available… they made an irrefutable case that the bacterium Helicobacter pylori is causing disease.

The prevailing dogma had been that if you had a gastric or duodenal ulcer, you were a type A stress-ridden personality. The high degree of stress in your life was linked to the generation of excess gastric juices and these ate a hole in your gut. Marshall and Warren noticed that this bacterium was present in every preparation from patients’ guts that they looked at. They collected more data, and found that in every patient they looked at, H. pylori was present in the diseased tissue. One of them got a test-tube full of H. pylori broth and drank it. He got gastritis: inflammation of the stomach lining and a precursor to a gastric ulcer. He took antibiotics, and was cured. The pair treated their patients with antibiotics and their ulcers cleared up.

Because they were creative, and courageous, they changed the existing paradigm. And this is important – you can overturn prevailing paradigms, you can change things. But in order to do that you have to have evidence, and a mechanism. Enough evidence, a solid explanatory mechanism, and people will accept what you say.

Which was a problem for Ignaz Semmelweiss. He had evidence, alright, but he lacked a mechanism. Semmelweiss worked in the Vienna General Hospital, where he was in charge of two maternity wards. Women would reputedly beg on their knees not to be admitted to Ward 1, where the mortality rate from puerperal fever was about 20 percent. In Ward 2, mortality was three or four percent. What caused the difference? In Ward 2 the women were looked after exclusively by midwives. In Ward 1, it was the doctors. What else were they doctors doing? They were doing autopsies in the morgue. And they would come from the morgue to the maternity ward, with their blood-spattered ties, and I hate to think what they had on their hands. Then they would do internal examinations on the women. Small wonder so many women died. Semmelweiss felt that the doctors’ actions were causing this spread of disease and said he wanted them to wash their hands before touching any of the women on his ward. Despite their affronted reactions he persisted, and he kept data. When those doctors washed their hands before doing their examinations, mortality rates dropped to around three percent.

The trouble was that no-one knew how puerperal fever was being transmitted. They had this idea that disease was spread by miasmas – ‘bad airs’ – and although the germ theory of disease was gaining a bit of traction the idea that disease could be spread by the doctors’ clothes or on their hands still didn’t fit the prevailing dogma. Semmelweiss wasn’t particularly popular – he’d gone against the hospital hierarchy, and he’d done it in quite an abrasive way, so when he applied for a more senior position, he didn’t get it, and left the hospital soon after. He was in the unfortunate position of having data, but no mechanism, and the change in the prevailing mindset had to wait for the conclusive demonstration by Koch and Pasteur that it was single-celled organisms that actually caused disease.

Collaboration and connectedness

Scientists are part of society. They collaborate with each other, are connected to each other, and are connected to the wider world. Although there have been some really weird people that weren’t. Take Henry Cavendish – the Cavendish laboratory in Cambridge is named after him. He was a true eccentric. He did an enormous amount of science but published very little, and was quite reclusive – Cavendish just didn’t like talking with people. If you wanted to find out what he thought, you’d sidle up next to him at a meeting and ask the air, I wonder what Cavendish would think about so-and-so. If you were lucky, a disembodied voice over your shoulder would tell you what Cavendish thought. If you were unlucky, he’d flee the room.

But most scientists collaborate with each other. Even Newton, who was notoriously bad-tempered and unpleasant to people whom he regarded as less than his equal, recognised the importance of that collaboration. He wrote: “If I have seen further than others, it is because I have stood on the shoulders of giants.” Mind you, he may well have been making a veiled insult to Robert Hooke, to whom he was writing: Hooke was rather short.

What about Darwin? Was he an isolated person, or a connected genius? We know that Darwin spent much of the later years of his life in his study at Downe. He had that amazing trip round the world on the Beagle, then after a couple of years in London he retreated to Downe with his wife and growing family, and spent hours in his study every day. He’d go out and pace the ‘sandwalk’ – a path out in the back garden – come back, and write a bit more. Darwin spent eight years of that time producing a definitive work on barnacles, and he didn’t do it alone. He wrote an enormous number of letters to barnacle specialists, and to other scientists asking to use work that they’d done, or to use their specimens to further the work he was doing.

He was also connected to a less high-flying world: he was into pigeons. This grew from his interest in artificial selection and its power to change, over a short period of time, various features in a species. So he wrote to pigeon fanciers. And the pigeon fanciers would write back. These were often in a lower social class and various family and friends may well have been a bit concerned that he spent so much time speaking to ‘those people’ about pigeons. And Darwin had a deep concern for society as well. He was strongly anti-slavery, and he put a lot of time (and money) into supporting the local working-class people in Downe. He was still going in to London to meet with his colleagues, men like Lyell and Hooker, who advised him when Alfred Wallace wrote to him concerning a new theory of natural selection. Now there’s an example of connectedness for you, and the impact of other people’s thought on your own! It was Wallace who kicked Darwin into action, and led to him publishing the Origin of Species.

That’s enough stories. I’m going to finish with another quote from Brian Greene:

Science is the greatest of all adventure stories, one that’s been unfolding for thousands of years as we have sought to understand ourselves and our surroundings. Science needs to be taught to the young and communicated to the mature in a manner that captures this drama. We must embark on a cultural shift that places science in its rightful place alongside music, art and literature as an indispensable part of what makes life worth living.
Science lets us see the wonder and the beauty of the stars, and inspires us to reach them.

Evolution in the NZ school curriculum

The teaching of evolution in New Zealand schools may seem secure, but it has faced many challenges, and these appear to be on the increase. This article is based on a presentation at the Evolution 2007 Conference, Christchurch.

Many people feel the antagonism between evolution and creationism is an issue only in the United States. However, creationism is becoming more visible around the world. Even in New Zealand, creationism, and its opposition to evolution, has a relatively long history and-as in many other countries-is currently increasing in prominence.

Evolution was first discussed in a New Zealand educational institution in 1871, when Otago University professor Duncan MacGregor pushed for the teaching of evolutionary biology. This led to moves to have him removed from his Chair, though these were ultimately unsuccessful.

New Zealand’s free, secular public education system was born in 1877. By 1881 there was some concern among the Protestant and Catholic churches that schoolteachers were being taught about evolution, thus supposedly losing the religious neutrality required of a secular system. However, school curricula contained no explicit mention of this worrying subject. New Zealanders appear to have viewed themselves as fairly open-minded in this area: Numbers & Stenhouse in 2000 noted that the NZ Herald, reporting on the 1925 Scopes trial in the US, “found it ‘hard to take the anti-evolution movement seriously'”.

However, in 1928 the Education Department published an addition to the national science syllabus that said “in the higher classes the pupils should gain some definite idea of the principle of evolution”. Though fundamentalist Christians were few in number they were extremely vocal: their immediate and heated response to the amended syllabus was so strong that the department backed down: students should not have to learn about human origins, but to “discover some part… of the great plan of nature”. This could be regarded as a win for the creationist camp, and was followed by the establishment of anti-evolution societies such as the Evolution Protest Movement.

In 1947 the Department of Education broadcasts to schools included a series of BBC programmes on evolution, How Things Began. Protest was swift and vociferous and included Labour party supporters worried about losing the wavering voter, as well as conservative Christian groups. The Minister of Education first suspended and then cancelled the broadcasts, despite strong opposition to this from teacher unions and other educationalists. Flushed with success, the creationist lobby attempted to get the Ministry to publish creationist articles in the School Journal, but the Minister declined. As public interest waned so too did the creationist movement, so that by the 1970s it seemed to have disappeared completely.

But at the same time, creationism in the US was experiencing resurgence, with the popular writings and presentations of Youth Earth Creationists such as Henry Morris (The Genesis Flood). In 1972 New Zealander Tony Hanne read Morris’ book and invited him on a tour of New Zealand. Visits by other US creationists followed, each generating considerable public interest in this country even though scientists in general rejected their claims. However, Numbers & Stenhouse (2000) also give the example of one university geologist who was so swayed by creationist rhetoric that he included works by Morris & Duane Gish in his own courses!

In 1982 the then Auckland Department of Education issued a creationist textbook for use in senior biology classes, a book which was widely distributed by the then Auckland College of Education’s Science Resource Centre. When questioned about the propriety of science teachers including creationism in their classes, a spokesman for the New Zealand Education Department responded that he found nothing wrong with science teachers including ‘scientific creationism’ in their classes, “as long as they’re presenting it as one possible explanation and not the only explanation”.

Scientists tended to feel that science, and evolution, had little to fear from creationism; it was viewed as a peculiarly American foible. Yet at the same time, the Creation Science Foundation (CSF) in Australia was expanding to become what was, by the 1990s, the world’s second-largest creation science organisation. This found fertile ground among religious conservatives in New Zealand, and also among our Maori and Pasifika communities (eg Peddie, 1995), and in 1994 the CSF opened a New Zealand branch, Creation Science (NZ).

1993 saw the introduction of a new Science curriculum, and the associated ‘specialist’ science curricula, for New Zealand schools. Evolution is mentioned explicitly only at Level 8 (Living World) of this document, which gives as a learning objective “students can investigate and describe the diversity of scientific thought on the origins of humans”. It goes on to say that students could be learning through “holding a debate about evolution and critically evaluating the theories relating to this biological issue” (my italics). This suggestion that there is more than one possible theory explaining evolution has left the door open for teachers and institutions who wish to bring creationism into the science classroom. Thus, in 1995 Peddie could comment, “… in this country some private schools, and some teachers within the state school system and home schooling systems, continue to teach creationism and debunk evolution.”

For example, in 2003 the Masters Institute, together with the organisation Focus on the Family, offered a workshop on intelligent design for teachers and parents, featuring speakers such as the Discovery Institute’s William Dembski. The session was billed as “an excellent learning opportunity that offers both a professional development opportunity and a fresh look at some knotty problems in science and biology” (Education Gazette, 22 August 2003). Focus on the Family has also distributed CD-ROMs based on the creationist tract Icons of Evolution to every secondary school in the country.

Concern from universities and the Royal Society was met by a response from the Ministry of Education stating that “it is not the intention of the science curriculum that the theory of evolution should be taught as the only way of explaining the complexity and diversity of life on Earth”-and that schools are free to decide their own approach to theories of the origins of life, within existing curriculum guidelines. Showing a lack of knowledge of evolution, the Ministry’s representative continued: “The science curriculum does not require evolution to be taught as an uncontested fact at any level. The theory of evolution cannot be replicated in a laboratory and there are some phenomena that aren’t well explained by it.”

We are now developing a new draft Science curriculum. This document, as well as emphasising the importance of students developing an understanding of the nature of science, recognises evolution as one of the organising themes of modern biology following Dobzhansky’s 1973 dictum, “Nothing in biology makes sense except in the light of evolution.” The curriculum document reads: “Students develop an understanding of the diversity of life and life processes. They learn about where and how life has evolved, about evolution as the link between life processes and ecology, and about the impact of humans on all forms of life”. One significant difference from the existing curriculum is that the term evolution is introduced in primary school: students in years 1 and 2 will “recognise that there are lots of different living things in the world and that they can be grouped in different ways,” and “explain how we know that some living things from the past are now extinct.” By year 13 they will be exploring “the evolutionary processes that have resulted in the diversity of life on Earth.”

The document was sent out for public consultation and the Biology component immediately drew the ire of conservative religious groups. Creation Ministries International (formerly the CSF) contacted members and supporters, asking them to lobby strongly for a reversion to the current status quo: “CMI does not suggest evolutionists be forced to teach about creation. What we do suggest is that freedom be retained for the presenting of both evolution-based and Creation-based frameworks of science. We support the teaching of evolution provided it is done accurately, ‘warts and all’, ie with open discussion of its many scientific problems included.”

And a submission for a private school stated that “… there is still no evidence to support the theory, [and]… to base [curriculum content] on an unproven theory is bizarre” (www.tki.org.nz/r/nzcurriculum/long_submissions_e.php). The writers went on to suggest that the curriculum would be better to speak of ‘diversity’, which they viewed as a much more suitable term.

There is also anecdotal evidence that many teachers also oppose the new curriculum in its present form-either because they feel uncomfortable or under pressure about it in the face of potential student, parent, and community opposition, or because they themselves have a creationist worldview. At a time when biology in its various forms is set to play an important role in New Zealand’s scientific and economic development, this is something that should concern us all.

Selected references (full references available from editor)

Numbers, R.L. & J. Stenhouse (2000) Antievolutionism in the Antipodes: from protesting evolution to promoting creationism in New Zealand. British Journal for the History of Science 33: 335-350. Peddie, W.S. (1995) Alienated by Evolution: the educational implications of creationist and social Darwinist reactions in New Zealand to the Darwinian theory of evolution. Unpublished PhD thesis, University of Auckland.

Communicating the nature of science: Evolution as an exemplar

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Science as taught at school is often portrayed as a collection of facts, rather than as a process. Taking a historical approach to the teaching of evolution is a useful way to illustrate the way science works.

The need for a scientifically literate population is probably greater now than ever before, given the rapid pace of change in science and technology. Members of such a population have the tools to examine the world around them, and the ability to critically assess claims made in the media. However, there are difficulties with conveying just what science is about and how it is done; in letting people know how the scientific world-view differs from “other ways of knowing”. This is particularly evident when dealing with evolutionary theory, often described as “just a theory”, and probably the only scientific theory to be rejected on the grounds of personal belief. How can we alter such misconceptions and extend scientific understanding?

Part of my role at Waikato University involves liaising with local and regional high school teachers of biology and science. Over the past few years I have received numerous requests from local secondary school teachers to provide a resource they could use in teaching evolution. Discussion with teacher focus groups revealed a number of content areas they would like to have available:

  • links to the New Zealand curriculum and to relevant web-sites,
  • evolutionary process (including the sources of genetic variation and how natural selection operates),
  • human evolution,
  • New Zealand examples,
  • evidence for evolution,
  • ways of dealing with opposition among students (and colleagues),
  • and the historical perspective.

These last two items are particularly significant, since modelling a way of presenting the historical development of evolutionary thought, and by extension the nature of science itself, offers a way of countering opposition to the theory of evolution.

I have deliberately used the example of evolution, because there is good evidence (eg Abd-El-Khalick and Lederman 2000; Passmore and Stewart 2000; Passmore and Stewart 2002) that altering the way in which evolution is traditionally taught offers the opportunity to show people the nature of science – what it is and how it works. For example, rather than taking a confrontational approach to their students’ beliefs, Passmore and Stewart (2000) provided a number of models of evolution and encouraged the students to determine which model best explained a particular phenomenon.

Similarly, William Cobern (1994) has commented:

“Teaching evolution at the sec-ondary level is very much like Darwin presenting the Origin of Species to a public who historically held a very different view of origins. To meet this challenge, teachers [should] preface the conceptual study of evolution with a classroom dialogue… informed with material on the cultural history of Darwinism.”

He goes on (Cobern 1995):

“I do not believe that evolution can be taught effectively by ignoring significant metaphysical (ie essentially religious) questions. One addresses these issues not by teaching a doctrine, but by looking back historically to the cultural and intellectual milieu of Darwin’s day and the great questions over which people struggled.”

Taking such an approach is highly significant in developing an understanding of the nature of science, since an historical narrative will not only place Darwin’s work into its historical and social context, but will also show how he applied the scientific method to solving his “problem” of evolution. This approach is central to the Evolution for Teaching website (sci.waikato.ac.nz/evolution – see NZ Skeptic 71; the other members of the website team are Dr Penelope Cooke of Earth Sciences, Dr Kathrin Cass, and Kerry Earl from the Centre for Science & Technology Education Research), and is also one I use in my own teaching, where every year I encounter students who have a creationist worldview. Such views may well become more common, given that there appears to be a coordinated effort to make material promoting Intelligent Design Theory (and denigrating evolutionary thought) available in schools.

This teacher-generated list, and the philosophy described above, informed the planning and design of the Evolution for Teaching website, which is hosted by the School of Science and Technology at Waikato University. First we felt it important to make explicit the nature of scientific hypotheses, theories, and laws, to overcome difficulties originating in differing understandings of the word “theory”. (Much of the language of science offers opportunities for such misunderstandings, since it invests many everyday terms with other, very specific meanings eg Cassels and Johnstone 1985; Letsoalo 1996.)

The site offers links to the NCEA matrices for Science and Biology, plus FAQs, book and site reviews, and a glossary.

Feedback has been almost entirely positive, with all the teachers attending its launch in March indicating that they would use it in their teaching and recommend it to their students. Without exception they found it attractive, easy to navigate, and informative, providing information at a level suitable for both themselves and their students. Student comments support this last point. Since the site went “live” in March 2004 it has received around 100,000 hits per month, indicative of a very high level of interest.