Easy fixes: simple corrections of some popular scientific misconceptions

A few months' ago I finally saw the film 'Gravity', courtesy of a friend with a home theatre system. Amongst the numerous technical errors - many pointed out on Twitter by Neil deGrasse Tyson - was one that I hadn't seen mentioned. This was how rapidly Sandra Bullock's character acclimatised to the several space stations and spacecraft immediately after removing her EVA suit helmet. As far as I am aware, the former have nitrogen-oxygen atmospheres whilst the suits are oxygen-only, necessitating several hours of acclimatisation.

I may of course be wrong on this, and of course dramatic tension would be pretty much destroyed if such delays had to be woven into the plot, but it got me thinking that there are some huge fundamental errors propagated in non-scientific circles. Therefore my Christmas/Hanukkah/holiday season present is a very brief, easy -on-the-brain round-up of a few of the more obvious examples.

1. The Earth is perfect sphere.
   Nope, technically I think the term is 'oblate spheroid'. Basically, a planet's spin squashes the mass so that the polar diameter is less than the equatorial diameter. Earth is only about 0.3% flatter in polar axis but if you look at a photograph of Saturn you can see a very obvious squashing.
   
   
2. Continental drift is the same thing as plate-tectonics.
   As a child I often read that these two were interchangeable, but this is not so. The former is the hypothesis that landmasses have moved over time whilst the latter is the mechanism now accepted to account for this, with the Earth's crust floating over the liquid mantle in large segments or plates.
   
   Geologist Alfred Wegener suggested the former in 1912 but is was largely pooh-poohed until the latter was discovered by ocean floor spreading half a century later. As Carl Sagan often said, "extraordinary claims require extraordinary evidence".
   
   
3. A local increase in cold, wet weather proves that global warming is a fallacy.
   Unfortunately, chaose theory shows that even the minutest of initial changes can cause major differences of outcome, hence weather forecasting being far from an exact science.
   
   However, there is another evidence for the validity of this theory, fossil fuel lobbyists and religious fundamentalists aside. I haven't read anything to verify this, but off the top of my head I would suggest that if the warm water that currently travels north-east across the Atlantic from the Gulf of Mexico (and prevents north-western Europe from having cold Canadian eastern seaboard winters), then glacial meltwater may divert this warm, denser seawater. And then the Isles of Scilly off the Cornish coast may face as frosty a winter as the UK mainland!
   
   
4. Evolution and natural selection are the same thing.
   Despite Charles Darwin's On the Origin of Species having been published in 1859, this mistake is as popular as ever. Evolution is simply the notion that a population within a parent species can slowly differentiate to become a daughter species, but until Darwin and Alfred Russel Wallace independently arrived at natural selection, there really wasn't a hypothesis for the mechanism.
   
   This isn't to say that there weren't attempts to provide one, it's just that none of them fit the facts quite as well as the elegant simplicity of natural selection. Of course today's technology, from DNA analysis to CAT scans of fossils, provides a lot more evidence than was available in the mid-Nineteenth Century. Gregor Mendel's breeding programmes were the start of genetics research that led to the modern evolutionary synthesis that has natural selection at its core.
   
   
5. And finally…freefall vs zero gravity.
   Even orbiting astronauts have been known to say that they are in zero gravity when they are most definitely not. The issue is due to the equivalence of gravity and acceleration, an idea which was worked on by luminaries such as Galileo, Newton and Einstein. If you find yourself in low Earth orbit - as all post-Apollo astronauts are - then clearly you are still bound by our planet's gravity.
   
   After all, the Moon is approximately 1800 times further away from the Earth than the International Space Station (ISS), but it is kept in orbit by the Earth's pull (okay, so there is the combined Earth-Moon gravitational field, but I'm keeping this simple). By falling around the Earth at a certain speed, objects such as the ISS maintain a freefalling trajectory: too slow and the orbit would decay, causing the station to spiral inwards to a fiery end, whilst too fast would cause it to fly off into deep space.
   
   You can experience freefall yourself via such delights as an out-of-control plummeting elevator or a trip in an arc-flying astronaut training aircraft A.K.A. 'Vomit Comet'. I'm not sure I'd recommend either! Confusingly, there's also microgravity and weightlessness, but as it is almost Christmas we'll save that for another day.
   

There are no doubt numerous other, equally fundamental errors out there, which only goes to show that we could do with much better science education in our schools and media. After all, no-one would make so many similar magnitude mistakes regarding the humanities, would they? Or, like the writer H.L. Mencken, would I be better off appreciating that "nobody ever went broke underestimating the intelligence of the (American) public"? I hope not!

Consumer complexity: engineering the public out of understanding

Last weekend my car stopped working. If a little knowledge is a dangerous thing, then an hour of internet research is probably worse. Convinced it was either the transmission or gearing, it turned out to be lack of petrol, the fuel gauge and warning light having simultaneously failed. At this point - breathing a sigh of relief that I wasn't facing an enormous repair bill so soon after an annual service - I realised that my knowledge of cars is extremely limited, despite having driven them for almost thirty years.

Obviously I'm far from being unique in this respect. In years past New Zealanders in particular were renowned for maintaining old cars long after other developed nations had scrapped them, with Australians referring to their neighbour as the place where Morris Minors went to die. However, anti-corrosion legislation put an end to such ‘canny Kiwi' tinkering so the country has presumably lost this resourcefulness when it comes to keeping ancient vehicles on the road.

Of course cars just aren't built to last any more: modern vehicles continue to be ever more fuel efficient and built of lightweight materials, but I doubt few will last as long as the classic cars still running after half a century or more. Built-in obsolescence is partly to blame, but the sophistication of today's designs means that their repair and maintenance is becoming ever more difficult without a complete workshop and diagnostic computer. As a teenager I learnt how to change my car's spark plugs but have since been told this should now only be undertaken by professionals as the tolerances required cannot be achieved by hand!

It isn't just motor vehicles that are affected by ever increasing complexity: high-tech consumer gadgets, especially those with integrated circuits (which let's face it, is most of them these days) are seemingly built to prevent tampering or repairs by the end user. Yet this is a fairly recent phenomenon. In my grandparents' generation the most sophisticated item in their house was likely to be a radio that used vacuum tube technology, but a cheaper alternative was available in the form of a do-it-yourself galena or pyrite crystal radio. Even children - Arthur C. Clarke amongst them - were able to build these self-powered devices, which worked rather well except for the fact that they had no speaker and so the user had to listen via headphones. It might seem unlikely that such as device was easy to construct until you remember that pioneer aircraft were built by bicycle manufacturers!

In contrast, the most advanced technological item my parents would have had until their twenties - when television sets started to become affordable - would have been a mass-produced transistor radio. Compared to the valve-infested sideboard gramophone, simple problems such as loose wires in these radios could be repaired with basic tools such as small screwdrivers, needle-nose pliers and a low wattage soldering iron. Whilst requiring a bit of skill and some understanding of wiring, such repairs were still within the range of many consumers.

Today, my experience suggests that the expendable consumerism that first became overt in the late 1960's is a key mind set in developed nations, with do-it-yourself work on gadgetry largely absent. In fact, it is frequently cheaper to buy a replacement item than to have it repaired or purchase the tools in order to attempt those repairs yourself. The speed with which newer models are released is such that it may even prove impossible to source a replacement part only a few years after the item has been purchased. This inevitably increases our distance from the inner workings of the ever more numerous high-tech consumer gadgets we now surround ourselves with. Surely it is a great irony that despite our ability to operate all of them, the vast majority of users have little idea of the fundamentals of the technologies involved?

My own experience with attempting to fix consumer electronics is rather limited, but I can see that manufacturers are deliberately trying to prevent this by using techniques such as hiding screw heads and using one-way pins, ensuring that any attempt to dismantle an item will snap parts within the casing. Additionally, the more sophisticated the technology, the more sensitive it seems to be. An example from a rather different sphere of activity comes from 1976, when a defecting Soviet Air Force pilot delivered a state-of-the-art fighter jet into the hands of Western intelligence. The MiG-25 ‘Foxbat' was discovered to be using valve-based rather than solid-state avionics, yet despite its primitive appearance the electronics were both extremely powerful and able to withstand immense physical stress, which is obviously of great importance in such aircraft.

Back to household gadgetry, I've seen an old cathode ray tube television repaired after water was accidentally tipped down the back of it, whilst flat screen computer monitors that were inadvertently cleaned with water - not by me, I hasten to add - were sent straight to the scrap heap. That isn't to say that there aren't a few brave souls who post internet videos on how to disassemble devices such as iPads in order to fix hardware issues, but I think you would either have to be very confident or quite rich before attempting such repairs. There are also websites dedicated to technology hackers, who enhance, customise or otherwise amend consumer gadgets beyond their out-of-the-box capabilities. Again, I don't have the confidence for this sort of thing, especially since there are hidden dangers: a digital camera for example contains a flash capacitor that can store - and deliver to the unwary - a charge of several hundred volts. Ouch!

So the next time someone declares their bewilderment with the ever-widening array of consumer gadgetry, or bores you with a piece of New Age nonsense, you should remember although we are surrounded with some extremely sophisticated devices, various causes have conspired to remove insight into their inner workings. Our consumerist age is geared towards acceptance of such items whilst limiting our involvement to that of end user. And of course I haven't even mentioned the ultimate fundamentals behind all this integrated circuitry, quantum electrodynamics...

Sandy strandings: the role of contingency in the beach biosphere

At irregular intervals over the past fifteen years I've been visiting the east coast beaches of New Zealand's Northland between Warkworth and Paihia. Although it's frequently good territory for finding shallow marine fauna via rock pools or along the tideline, a recent visit was enhanced by exciting finds unique in my experience. I usually expect to see the desiccated remains of common species such as sand dollars, scallops, whelks and assorted sea snails, but coastal storms just prior to my arrival brought an added bonus. Two days of exploration along three beaches was rewarded with a plethora of live - but presumably disorientated - creatures such as common sea urchins (Evechinus chloroticus) and large hermit crabs (Pagurus novizealandiae), along with some recently-deceased 5- and 7-arm starfish. As you might imagine, several species of seabird, notably terns and gulls, were having a gastronomic time of it with all these easy pickings.

At the nearby Goat Island Marine Discovery Centre run by the University of Auckland I told our marine biologist guide about my two daughters' attempts to save some of the homeless hermit crabs from the gulls by offering suitable shells as new abodes. The biologist responded with a story of a visitor who had thrown live starfish back into the water after a mass stranding. Someone else commented that his actions wouldn't make a difference; our guide said that as he continued throwing them, the man replied "It made a difference to that one...and that one...and that one..."

Common sea urchin (Evechinus chloroticus)

Of course we cannot hope to make much of a difference with such good intentions: nature, after all, is essentially immune to human morality and empathy, with survival at a genetic level the only true sign of success. But do small-scale events whose aftermath I recently experienced - in this case a few days of stormy weather and the resultant strandings - have any long-term effects on the local ecosystem?

Apart from a mass marooning of the large barrel jellyfish Rhizostoma pulmo on a North Wales beach around thirty years ago, I haven't experienced anything similar before. But then until three years ago I didn't live near the sea, so perhaps that's not unlikely! There are fairly frequent news stories from around the world about mass whale or dolphin beachings put down to various causes, some man-made such as military sonar. But as these events involve animals larger than humans they make it onto the news: for smaller creatures such as the crabs and urchins mentioned above, there are unlikely to be any widely-disseminated stories.

Australian southern sand star (Luidia australiae)

It may seem improbable that the balance between organisms could be profoundly altered by local events, but it should be remembered that a few, minor, outside influences over the course of less than a century can wipe out entire species. For example, although the story of how a single cat was responsible for the demise of the Stephens Island wren around the start of the Twentieth Century is an oversimplification of the events, there is evidence that current human activity is inadvertently causing regional change.

One well-known recent illustration is from the Sea of Cortez, where too much game fishing, especially of sharks, may have led to the proliferation a new top predator, the rapidly spreading Humboldt squid. Estimates suggest that the current population in the region is over 20 million individuals (which suits the local squid-fishing industry just fine), but extraordinary considering none were known in the region before about 1950. Two-metre squid may not sound menacing compared to sharks, but the Humboldt squid is a highly-intelligent pack hunter with a razor-sharp beak and toothed suckers on its tentacles, so diving amongst them is probably not for the faint-hearted.

The TV series Cosmos: A Spacetime Odyssey contained a good introduction to the five mass extinctions of the past 450 million years, but it isn't just these great dyings or even El Niño that can upset ecosystems; we may find out too late that relatively minor, local changes are able to trigger a chain reaction at a far wider level. The evolutionary biologist Stephen Jay Gould repeatedly emphasised the importance of historical contingency and the impact of unpredictable, ad-hoc events on natural history. The modern synthesis of evolutionary biology includes the notion that speciation can result from isolation of a population within an 'island'. This latter differs from the strictly geographical definition: a lake, or even an area within a lake, can be an island for some species. If, for example, local changes cause a gap in the ecosystem, then this gap might be filled by an isolated population with the 'fittest' characteristics, in the sense of a jigsaw piece that fits the relevant-shaped hole.

Hermit crab (Pagurus novizealandiae)

Back to the beach. American marine biologist Rachel Carson's 1951 award-winning classic The Sea Around Us contains an early discussion of the recycling of nutrients within the oceans, but we are now aware that the sea isn't remotely self-contained. My favourite example of an intricate web of land, sea and even aerial fauna and flora centres on the Palmyra Atoll in the Pacific Northern Line Islands. Various seabirds nest in the atoll's high trees, their nutrient-rich guano washing into the sea where it feeds plankton at the base of the offshore food chain. The plankton population feeds larger marine fauna, with certain fish and squid species in turn providing meals for the seabirds, thus completing the cycle. Such a tightly-knit sequence is likely to undergo major restructuring of population densities if just one of the players suffers a setback.

I appear to have followed Stephen Jay Gould's method of moving from the particular to the general and may be a little out of my depth (okay, call it a feeble attempt at a pun) but it certainly gives food for thought when local shallow marine populations appear to suffer after only a few days of mildly inclement weather. If there’s a moral to any of this, it’s that if natural events can affect an ecosystem in unpredictable ways, what havoc could we be causing, with our pesticide run-off, draining of water tables, high-energy sonar, over-fishing and general usage of the oceans as a rubbish dump? The details may require sophisticated mathematics, but the argument is plain for all to see.

Mythbusting: bringing science into the arena

My elder daughter is a big fan of the Discovery Channel show Mythbusters, who have spent eleven years testing myths (and not a few Hollywood set pieces) via science, technology, engineering and frequent resort to high explosives. Therefore, as a birthday treat I recently took her to the live Behind the Myths tour, fronted by Mythbusters hosts Adam Savage and Jamie Hyneman. Considering how macho the series frequently is - it's only female presenter, now left, is a vegetarian who was made to eat live bugs - it was interesting to see what and how the science was presented live.

In some respects it lived up to its reputation, with the hosts apologising for the lack of on-stage explosions but claiming their intentions were to 'blow the mind' instead of say, a pick-up truck or hot water cylinder. That's not to say that there weren't some fiery moments, including several montages of explosions and the infamous paintball machine gun aimed at someone wearing a suit of replica armour. Considering a large percentage of the audience consisted of pre-teens with their parents, the big bang elements were very much appreciated. But since the presenters have a special effects rather than science background, was there anything worthwhile beyond the showmanship?

Apart from a brief introduction to Newton's Second Law of Motion (force equals mass times acceleration, in case you weren't sure) there wasn't much of the classroom about the show. Except that for two hours Hyneman and Savage managed to painlessly convey a lot of scientific ideas. Examples included:

• Archimedes' quote about using a lever to move the world was demonstrated via a fairground high striker and different sized mallets;
• Perception, thanks to a point of view camera and some comedic cheating;
• Tessellation and human mechanics, with four interlocked reclining men able to support their own weight when their chairs were taken away;
• Friction via a circus-like stunt, in which Savage was lifted high above the stage thanks to the strength of interwoven telephone directories.

Although it might be quite easy to lose sight of the science behind all the razzmatazz, perhaps that was the point. These demonstrations reminded me of the Royal Institution's Christmas lectures, aimed primarily at 'young people' and barely a decade shy of being two hundred years' old. Unlike the television series, which has sometimes revisited experiments - occasionally reversing the original results in the process - the Behind the Myths tour was more a solid grounding in basic physics, with a little chemistry and biology thrown in. If anything, the most obvious outcomes would be to promote curiosity by recognising that science is deeply embedded in everyday life, and that exploring reality can be enormous fun.

The first section of the show had Adam Savage demonstrate juggling whilst explaining how he taught himself the techniques. Since his recollection discussed patience, perseverance and learning from your mistakes, you could say he was presenting in microcosm key elements of the scientific enterprise,' eureka' moments excepted.

I'm uncertain how many in the audience would cotton on to the science-by-the-backdoor aspect of the show. If anything, the children present may be more likely to want a career in movie special effects than in science, but the sense of wonder it generated may have also rubbed off on the adults present. Hyneman and Savage have become well-known enough in their support of STEM subjects and dislike of woolly thinking (take note, Discovery Channel , home of Finding Bigfoot) to have spoken at the 2006 annual convention of the US National Science Teachers Association, as well as presenting a demonstration to President Obama. That's no mean feat for a couple of special effects technicians with no formal science training. Let's hope that the some of the audience sees beyond the whizz bangs into the wonderful world that scientific exploration offers!