No mere kidding around

26 April 2013 by Malcolm Campbell, posted in Biology, Science Communication

Children are born true scientists. They spontaneously experiment and experience and re-experience again. They select, combine, and test, seeking to find order in their experiences - "which is the mostest? which is the leastest?" They smell, taste, bite, and touch-test for hardness, softness, springiness, roughness, smoothness, coldness, warmness: they heft, shake, punch, squeeze, push, crush, rub, and try to pull things apart. R. Buckminster Fuller (1895-1983)

It’s hard to beat the buzz that you can get from the wide-eyed wonder of kids enthralled by science. Nowhere is this in more concentrated form that at science fairs. At big fairs, there are isles upon isles of kids, standing in nervous anticipation, ready to share what they discovered. Sure, some of them were aided by parents, a teacher, or some other mentor, but the pathway and the outcome was theirs.

At a science fair, kids have a chance to share their story of discovery – what inspired them, the route they took, the cool things they found. To a trained scientist, sometimes the student’s story seems too haphazard, too ambitious, too unrealistic.  But this is precisely what is wonderful about it. Kids at science fairs are of an age where they have an enthusiastic passion for discovery, combined with a reasonable sense of the scientific method. Importantly, they are also at an age where they are, generally, untainted by the pragmatic realism of adulthood – a pragmatism that constrains thinking, and quells enthusiasm.

For the past three years, I have had the good fortune to host the city-wide science fair at my home institution. Being no more than host affords me the opportunity to do nothing other than leisurely chat with the participants. And what a wonderful opportunity that is.

The scope of the projects is remarkable – they span the scientific alphabet from astronomy to zoology. As a biologist, I admit to being drawn to projects that have a life sciences bent. This year, two particular projects caught my attention. Both projects focused on mould of one sort of another. Both projects were undertaken by students with the greatest of enthusiasm. And yet, despite these similarities, the two projects could not have been more different in terms of the technology necessary for their execution, and, by inference, their apparent sophistication.

The first project was the brainchild of a pair of students who were just a little over a year away from completing high school.  The young woman and young man in question had been inspired by mouldy food in their refrigerator. Their specific inspiration was yogurt that was well past its prime. How, they wondered, could the refrigerator life of yogurt be extended in a “natural way”? They speculated that addition of essential oils from plants might be the solution. Specifically, they hypothesised that a concentration of a given essential oil could be found that, when added to yogurt, would decrease the likelihood of mould formation and would also taste good.

The notion behind the yogurt project was a good one.  Essentials oils are a specific class of plant extracts. They are usually extracted through a distillation process, collecting volatile compounds that are released from plant matter when it is heated. As such, essential oils generally contain a complex mixture of chemicals, many of which have distinctive aromas or flavours. These plant-produced molecules, or phytochemicals, can have a variety of bioactive effects. Phytochemicals are made by plants to fulfil a range of functions. Amongst these, some phytochemicals, including those found in essential oils, function as antimicrobials, compounds that impede the growth and/or survival of bacteria or fungi or both. The pair of science fair students proposed that the aroma, flavour, and antimicrobial properties of essential oils would make them good candidates for improving yogurt longevity.

As you might well imagine, the yogurt project had a nice simple experimental design.  The properties of several different essential oils were tested individually. This included clove oil, vanilla oil, and several others. Different dilutions of essential oils were mixed into separate yogurt containers. The doctored yogurt then had two fates. Half of the sample was stored in the refrigerator for 45 days, and subsequently scored for the extent of microbial colonies (“growies”) that it contained. The other half of the sample was subjected to a taste test – not, it is worth noting, after 45 days, but a few days after having had the essential oil mixed in. The students enlisted friends and family in blind taste tests, using a rank-order numerical score – a brilliant design that circumvented problems with taste testers using a subjective scale. With this experimental design, for each essential oil, at each concentration, the young scientists had two quantified measures – colony count and rank-order flavour. Importantly, they had three replicates for each sample. While their statistics were pretty rudimentary (means and standard deviations), they understood that variation was important. They tallied their data in a matrix, and made a judgement of the optimal oil, and the optimal concentration. They then queried the national health authority to see if their findings would be palatable from a regulatory perspective. The students had thought it all through – from concept to application. It was beautiful.

While the yogurt project was elegant in its simplicity and execution, the enthusiasm the students had for the project was even better. They had suspected that they might find precisely what they did discover. There was, after all, a published literature showing that yogurt supplemented with essential oils could function to delay the appearance of microbial growth. But the students had effectively reproduced the work in the literature, and extended the process of discovery themselves. They designed the experiment. They acquired the materials. They set it up. They recorded the results. They reported the findings. Importantly, they had ideas about where to take the work in the future. And they did it with a gusto that only kids can. This – this is what makes science fairs fantastic.

The second project was no less fantastic but yet a sharp contrast to the first. Conducted by two young gentlemen in the last year of high school, the second project was a test of gene function. The project relied on genetic engineering and microscopy. Where the yogurt project was conceived and gestated in the kitchen, the second project was very much a product of a laboratory.

The test of gene function was, in some respects, as conceptually simple as the yogurt project. At the core of the project was the simple concept that, if a gene was involved in a particular process, loss of that gene’s function should result in a reduction, or even disappearance, of the process. In keeping with this, elevation of the same gene’s function should enhance the process in which it is involved. If one envisages a gene as a simple light switch, the idea is that if the switch is turned off, the light is also off; whereas, if the switch is in the “on” position all the time, the light is also on.  In the case of the second project, the gene in question was proposed to be involved in conferring disease resistance to plants.

Like animals, plants succumb to infectious diseases. Unlike animals, plants don’t have an antibody-based immune system to defend themselves against disease. Instead, plants respond to infectious disease by deploying an array of largely chemical-based defences. These defences can range from reinforcement of the exterior of cells, creating a passive barrier to infection, to the production of compounds that function as antibiotics, actively attacking the infectious agent. The second project aimed to examine the role that two plant genes played in mounting a defence against infectious disease.

The two students focused their attention on Hyaloperonospora arabidopsidis, a water mould that creates a disease called downy mildew on susceptible hosts. The host for this particular mould is the experimental workhorse of plant biologists, mouse-ear cress, Arabidopsis thaliana. Mouse-ear cress, or simply arabidopsis as plant scientists call it, is a small, weedy species that can proceed from germinating seedling to producing many thousands of seeds itself in six weeks. This rapid life cycle, coupled with simple genetics, a completely sequenced genome, and an array of biological resources with which to dissect its growth and development, have made arabidopsis the darling of botanists – their version of the fruit fly.

Working together with a team of researchers at a nearby university, the students tested the hypothesis that two related genes provided arabidopsis with some resistance against downy mildew.  In the first set of experiments, they made use of genetic mutants. One mutant harboured a single mutation that resulted in the loss of the function of one of the two genes. The other mutant harboured a single mutation that resulted in the loss of the function of the second gene. The students then investigated whether downy mildew infection was greater in one mutant versus the other relative to plants where the genes where still functional. The students examined downy mildew infection by using microscopy to quantify the growth of the mould on leaves that had been deliberately inoculated with a known amount of mould. The students found that the mould grew to a much greater extent on the mutants that had lost the function of the genes. It didn’t matter which of the two genes was mutated, the plants were compromised in their ability to ward of downy mildew infection.

In the second set of experiments, the two students tested the ability of the same two genes to increase resistance to downy mildew. Working together with a graduate student, the students created genetically-engineered plants to test their hypothesis. In these experiments they created one set of genetically engineered-plants where the activity of one of the genes was elevated all of the time. In a second set of genetically-engineered plants, the activity of the second gene was elevated. If the genes functioned to confer resistance to downy mildew, the genetically engineered plants were designed so that they should show enhanced resistance relative to plants where the two genes had “normal” levels of activity. Using the same microscopy technique to measure downy mildew infection, this is exactly what the students found.

Taken together, the students two lines of experimentation showed that two genes where both necessary and sufficient to confer resistance to downy mildew. Their work ascribed a function to these genes that had been previously unknown, and suggested a mechanism that might be used to help crop plants resist an economically important disease. This was certainly not lost on the students. Their boundless enthusiasm for the project was, frankly, every bit as infectious as the plant disease they studied.

I was struck by the incredible similarities between the two projects – the elegant simplicity of the hypotheses that were tested, the clarity of the experimental design, the use of replication, the beauty of the results that emerged, and the implications of the discoveries. Mostly I was struck by the fervour shared by the students. They had partaken in the process of discovery and were eager to share it.

This said, there were also striking differences between the projects, particularly with respect to their inception, their execution and their presentation. The first project was clearly the product of a home environment. It was “kitchen science” in every sense of the phrase. By contrast, the second project was clearly the product of an academic laboratory environment. It is impossible to imagine any student conducting such experiments at home. The reagents and technical expertise necessary to undertake such research are normally not resident in a home environment.  What’s more, the manner in which the results were presented, making use of an academic research conference-style poster, set it apart from most of the other science fair presentations.

Recently, there has been some attention paid to the sort of differences observed between the two projects described above. There is concern that projects of the sort conducted in university research laboratories place the students involved at an unfair advantage. The concern is that this advantage is only available to a privileged minority of potential science fair participants. The advantage that university-based science fair projects confers can function as a discouragement to those students who don’t have access to an environment, like a university, to undertake a project that appears, at least at first blush, more sophisticated. Even when proximity to such facilities is not an issue, there are other cultural barriers that prevent some students from securing assistance in their projects from universities and similar institutions. These cultural barriers are reinforced when students that have accessed such institutions are advantaged at science fairs.

These are important considerations that warrant careful attention. Some have suggested that perhaps prohibiting university-aided science fair projects would be a solution to unfair advantage. Adopting this approach would be unfortunate. In fact, there is a strong case to be made that universities should be doing more to provide opportunities for science fair students to participate in the research enterprise. As university research is largely funded from the public purse, effort should be made to connect a broader segment of society with that research. Science fair students provide an excellent opportunity to do just that. What better way to convey the excitement and importance of research to the broader public than to provide opportunity to participate directly in that research? Some may have concerns about the capacity of pre-university students to engage in projects that would not be a drain on limited research funds, but evidence suggests the contrary. As the university host of the downy mildew project said: “The science fair students were every bit as dedicated as the best university students, with hands-on skills matching that of many new graduate students.”

There’s also something to be said about engaging the relatively uninitiated in university-based research. Kids are very naturally outside-the-box  thinkers, and can often bring a startlingly refreshing perspective to problem solving. Most university professors can recount how they received a letter from a school-age student interested in doing a project that would literally change the world, if only there were enough resources and time available. Most of the responses to these letters gently move the student on to a more “realistic” goal, but one that is certainly less likely to be a game changer. What an incredible opportunity lost. Maybe we should be adopting more ideas from kids, rather than rebuffing them.

In keeping with this theme, Jack Andraka, a 15-year-old science fair participant, began his prize-winning research by approaching a university to assist him with one of those completely “outside-the-box” projects. Moved by the recent death of a close family friend, this student was inspired to work on a project to develop a better means to detect pancreatic cancer. He wanted to develop a highly sensitive detector that would make use of protein-coated nanotubes to sense an early marker of pancreatic cancer. Clearly, this was no kitchen project. Many universities may have pushed back on a request to pursue such a project, but, fortunately, not in this case.  Instead, this young man is now moving forward with his device, which actually holds real-world promise. He’s being touted as a “modern day Edison”. How many other science fair ideas are out there that might really be transformative? Probably a good many.

So, rather than limiting university-based science fair projects, a better solution might be to examine how science fair projects are evaluated. The adjudication of science fair projects must focus on the manner in which the science was conducted, rather than the technological sophistication of techniques employed in the execution and presentation of the work. For example, the two mould projects described here actually differed very little in terms of the scientific process. In fact, it could be argued that the scientific process was equally sophisticated. The technology used in the execution and presentation of the science certainly differed, but the basic scientific principles and the engagement with those principles by the students did not. Provided science fair evaluators are not swayed by technology, and focus instead on scientific process, then perhaps there will be no issue.

It’s comforting to know that this solution may already be in action. Both of the mould projects that stood out at our city-wide science fair were silver medal recipients. Science was judged against a scientific standard, and not on the basis of technology involved.  This said, at the end of the day, science fairs are realty not about the awarding of medals and prizes anyway. Instead, they are about creating a forum, a platform, for kids to do what kids do best, explore the novelty in the universe around them. We shouldn’t care whether this takes place in the kitchen or the lab, we should just make sure that we nurture it, support it, promote it.

References:

Bednarek P (2012) Chemical warfare or modulators of defence responses–the function of secondary metabolites in plant immunity. Current Opinion In Plant Biology 15: 407-414

Bencze JL & Bowen GM (2009) A national science fair: Exhibiting support for the knowledge economy. International Journal of Science Education 31: 2459-2483

Coates ME & Beynon JL (2010) Hyaloperonospora arabidopsidis as a pathogen model. Annual Review of Phytopathology 48: 329-345.

Czerniak CM (1996) Predictors of Success in a District Science Fair Competition: An Exploratory Study. School Science and Mathematics 96: 21-27

Dixon RA (2001) Natural products and plant disease resistance. Nature 411: 843-847.

Gifford VD & Wiygul SM (1992) The Effect of the Use of Outside Facilities and Resources on Success in Secondary School Science Fairs. School Science and Mathematics 92: 116-119

Lucera A et al. (2012) Food applications of natural antimicrobial compounds. Frontiers in Microbiology 3: 287

Otaibi MA & Demerdash HE (2008) Improvement of the quality and shelf life of concentrated yoghurt (labneh) by the addition of some essential oils. African Journal of Microbiology Research 2: 156-161

Rillero P (2011) A Standards-Based Science Fair. Science and Children 48: 32-36

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One Response to “No mere kidding around”

  1. erikamorgan Reply | Permalink

    It was really nice to read the blog. The information in the blog is quite helpfull. Keep posting.

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