The Best Australian Science Writing 2012
Page 14
Recall that we mentioned earlier how physical anthropologists can measure strength from fossil bones because those bones grew larger in response to muscular stress. What causes the muscular stress, of course, is exercise – lots of it.
High levels of strenuous physical activity, particularly at a young age, have a strong developmental influence on growth. This is why ancient humans like Neanderthals and Homo erectus had such thick bones and strong muscles in the first place. A telling fact is that only modern competitive athletes like champion tennis players have bones anywhere near as big as those ancient humans. Every day in the life of a Neanderthal, it seems, was a Wimbledon final.
The same principle is probably responsible for the remarkable speed and endurance of the Greek oarsmen. The bones of ancient Greeks are not as robust as those of Neanderthals, but they are denser and stronger than the average modern man’s. That’s because everybody in ancient Greece, not just oarsmen, lived tough lives featuring lots of strenuous exercise.
One of the quickest ways to develop very strong bones, for example, is to live in mountainous country. Greece just happens to be the most mountainous country in Europe. Even Greek aristocrats walked everywhere and maintained a highly athletic culture from early youth. Studies of how quickly ancient Greek children developed robust bones also seem to show that they began working on labour-intensive adult tasks from the age of three onwards. No matter how diligently a modern athlete trains, it’s pretty hard to match a gruelling regimen like that.
However disheartening the news, then, there is apparently some consolation to be taken from the superior feats of Neanderthal armwrestlers, ice age Aboriginal runners and ancient Greek super-sailors. While they may have dented our pride by besting us thoroughly in physical strength, there turns out to be hope for us after all.
True, we might not be able to recover the super-sharp vision of Thomas Chaseland or the explosive muscular power of our earliest hominin ancestors, both of which are genetically governed. But we could match the solid bones of Homo ergaster and Homo erectus, the fleet feet of ice age Aboriginal men, and the unwearying endurance of Athenian rowers. All we’d have to do is take a brief holiday from our generally couch-potato lives. There are, however, two problems.
The first is that even the most dedicated gym junkie rarely matches the level of exertion that many tribal peoples do. For example the Tarahumara, a cave-dwelling people from northern Mexico famed for their endurance running, produce about 42,000 kJ of work effort during one of their 24–48 hour ‘kickball’ races – more than modern Tour de France competitors over a comparable period.
Then there’s the problem that human strength develops most of all in one very specific window in our adolescent years. The same study that found tennis players have arm bones almost as robust of those of Homo erectus also showed that these developmental effects are most pronounced between the ages of eight and 14.
I had my own confirmation of this while researching my book, Manthropology, when a physical trainer in the Australian Army told me that recruits from the 1980s onwards began ‘flunking out of basic training with shin splints and fractures to their weakened leg bones because they’d all worn soft-soled runners as kids rather than the hard leather shoes of earlier generations.
So while our children could, it seems, regain the glories of our ancestors (if we only heed the lesson and expose them to the environmental stresses those ancestors faced), we ourselves have apparently missed our chance. There’s nothing left for us except to lie back and smile wryly: the weak truly have inherited the Earth.
Real men
Energy
A wee solution
Lachlan Bolton
The swimming pool is the gathering place for swarms of noisy neighbourhood children enjoying the refreshing sensation of cool, sparkling water. All is well until … a wee surprise diffuses through the water particles.
One child doing laps of breaststroke is intrigued by the presence of a patch of warm water that still hasn’t assimilated with the surrounding colder water. Meanwhile, another young child is proudly projecting a stream of pool water at his friend through his teeth.
Is this wee problem a rare phenomenon? Not according to a 2009 US survey of 1000 adults, which found that 17 per cent of people admitted to weeing in the pool. Imagine the actual percentage if you include the adults who were too embarrassed to own up, and the mind boggles when you start to estimate the percentage of children who relieve themselves in the pool.
The urge to urinate typically occurs when the bladder is holding between 150 and 300 millilitres of urine. So, for every wee, at least 150 millilitres of aqueous urea, ammonia, uric acid and other organic chemicals are dispensed into the ‘clean’ water.
Alarmingly, an average 37 millilitres of this ‘clean’ water is then swallowed by a casual swimmer, while 128 millilitres is swallowed by a swimmer doing laps over a 45 minute period, according to a 2006 US Environment Protection Agency study.
There is a misconception that pool chlorine breaks up urine. In fact, the organic compounds in urine combine with chlorine to form nasty chloramines. Unlike chlorine, these molecules do not evaporate easily. They also pass untouched through many pool filtration systems, allowing them to hang around for long periods of time. It is little surprise that wee in a pool can lead to respiratory problems, eye irritations, throat infections and diarrhoea.
Is there a solution to this nature-calling chemical problem? Could it be an instant electric shock or even the release of a bright red dye? It just happens that a urine-indicating dye does exist, but imagine the face of my 18-year-old sister after coming home from a sweaty netball training session and diving into the pool. Her face would be a brighter red than the red dye responding to the urea excreted through the pores of her skin.
Thankfully, I have come up with a solution to this problem. It is the Wee-Cam: a thermal-imaging infrared camera that detects minute changes in thermal water conditions. At the point of expulsion, the infrared camera would detect a bright expanding cloud projecting upwards from the guilty swimmer; the cloud would gradually disperse and fade into the darker background colour on the infrared image. The Wee-Cam could also double as a security camera to warn the pool owner of intruders or infants who happen to stray into the pool area. The Wee-Cam is definitely a wee solution to a common problem that could make your pool the cleanest and healthiest in the neighbourhood.
DIY science
Dilutions
Diamond planets, climate change and the scientific method
Matthew Bailes
Recently my colleagues and I announced the discovery of a remarkable planet orbiting a special kind of star known as a pulsar.
Based on the planet’s density, and the likely history of its system, we concluded that it was certain to be crystalline. In other words, we had discovered a planet made of diamond.
Following the publication of our finding in the journal Science, our research received amazing attention from the world’s media. The diamond planet was featured in Time magazine, the BBC and China Daily, to name but a few.
I was asked by many journalists about the significance of the discovery. If I were honest, I’d have to concede that, although worthy of publication in Science, in the field of astrophysics it isn’t that significant.
Sure, there are probably somewhere between six and a dozen quite important theoretical astrophysicists around the world who would have been thrilled at the news (after all, the diamond planet fills a gap in the binary pulsar family). But in the overall scheme of things, it isn’t that important.
And yet the diamond planet has been hugely successful in igniting public curiosity about the universe in which we live. In that sense, for myself and my co-authors, I suspect it will be among the greatest discoveries of our careers.
Our host institutions were thrilled with the publicity and most of us enjoyed our 15 minutes of fame. The attention we received was 100 per cent positive, but how different that could have been.
Imagine for a minute that, instead of discovering a diamond planet, we’d made a breakthrough in global temperature projections. Let’s say we studied computer models of the influence of excessive greenhouse gases, verified them through observations, then had them peer-reviewed and published in Science.
Instead of sitting back and basking in the glory, I suspect we’d find a lot of commentators, many with no scientific qualifications, pouring scorn on our findings. People on the fringe of science would be quoted as opponents of our work, arguing that it was nothing more than a theory yet to be conclusively proven. There would be doubt cast on the interpretation of our data and conjecture about whether we were ‘buddies’ with the journal referees.
If our opponents dug really deep they might even find that I’d once written a paper on a similar topic that had to be retracted. Before long our credibility and findings would be under serious question.
But luckily we’re not climate scientists.
Our work is part of the astonishing growth in our knowledge of the universe, made possible by huge leaps forward in instrumentation and telescope technology.
* * * * *
It may come as a big surprise to many, but there is actually no difference between how science works in astronomy and climate change – or any other scientific discipline, for that matter.
We make observations, run simulations, test and propose hypotheses, and undergo peer review of our findings. We get together (usually in nice locations around the world) and discuss and debate our own pet theories, become friends and form a worldwide community.
If you are a solid state physicist, an astronomer, or doing laser optics, the world is happy to celebrate your discoveries, use them in new products such as WiFi, and wonder about the growth in knowledge and technology.
Of course we all make mistakes. But eventually the prevailing wisdom of the community triumphs and the field advances.
It’s wonderful to be a part of that process.
But on occasion those from the fringe of the scientific community will push a position that is simply not credible against the weight of evidence. This occurs within any discipline. But it seems it’s only in the field of climate science that such people are given airtime and column inches to espouse their views. Those who want to ignore what’s happening to Earth feel they need to be able to quote ‘alternative studies’, regardless of the scientific merit of those studies.
In all fields of science, papers are challenged and statistics are debated. If there is any basis to these challenges they stand, but if not they fall by the wayside and the field continues to advance. When big theories fall, it isn’t because of business or political pressures – it’s because of the scientific process.
Sadly, the same media commentators who celebrate diamond planets without question are all too quick to dismiss the latest peer-reviewed evidence that suggests that man-made activities are responsible for changes in concentrations of CO2 in our atmosphere.
The scientific method is universal. If we ignore it in certain disciplines, we do so at our peril.
The media
Other worlds
Discovery
Storm front
Jo Chandler
To a patient scientist, the unfolding greenhouse mystery is far more exciting than the plot of the best mystery novel … Impatience increases when one realizes that it is not the fate of some fictional character, but of our planet and species, which hangs in the balance as the great carbon mystery unfolds at a seemingly glacial pace.
Professor David W Schindler, Nature, 1999
The flight’s delayed – not long, just enough time to sit, breathe. Time to recover from the frenzy required to get this far. To remember what has inevitably been forgotten. Let it go. Time to survey fellow travellers, divine the fragments of their stories – that impolite, hard-wired journalistic intrusion. Time to enjoy a little of the magic that always occupies this moment.
Routines are distorted and duties discarded. Nothing left to do but anticipate the adventure. This is the point of transition between realities, stepping out of the ordinary and into possibility. The departure gate is the wormhole. It’s why I love airports. They will be a hard habit to break.
Today I begin a journey south, deep south, abandoning family to share a pure, white Christmas with a group of strangers at the end of the Earth. A place with no economy, no shopping crowds, no shortage of parking, no avenues of glass-encased, climatecontrolled malls. A place where the natural breath and pulse of the planet can still be felt. First a plane to Hobart, then another to Antarctica, climbing down into the high latitudes until the lines of longitude converge and we fall off the map defining the habitable world.
But for now, we wait at the gate. Fellow travellers are transfixed by wide screens suspended overhead, loudly spruiking last-minute gift ideas. The strident sales pitch is interrupted momentarily by breaking news. ‘Wild storms lash America.’ The US is brought to its knees by furious nature. The White House is barely discernible, obscured by pale clouds of swirling blizzard. The weather gods are making mischief. Or indulging in a little eloquent smite? Our aircraft, we are crisply informed, is now ready for boarding.
‘COPENHAGEN COP-OUT’ cries the front page of the Sunday broadsheet I shake out as I settle in my seat. ‘The Copenhagen climate change conference last night appeared to have ended in chaos,’ the report opens. ‘A handful of developing nations rejected a last-minute accord stitched up in a backroom between the world’s biggest emitters and announced unilaterally by US President Barack Obama.’ Years of negotiations on a new international climate treaty have vanished, poetically, in so much hot air, and the future is adrift.
I fold up the paper and shut my eyes as the engines scream, the cue to silently offer up – to whatever deity might be on my wavelength – the ritual takeoff prayer. It rings through my interior world even more hollowly than usual, but I can’t not do it – years of indoctrination have compelled a reflex attachment to Catholic insurance. This time, though, it’s about more than getting the plane down in one piece.
Later I will read climate doomsayer Clive Hamilton’s bleak reflection on the news that day: ‘In light of the fierce urgency to act, there was a sense at the Copenhagen conference that we were witnessing not so much the making of history, but the ending of it.’ It was a day which would ‘live in infamy’, according to a commentator in London’s Independent. An eminent Australian scientist caught up in the desperate, last-ditch fury of the talks will later confide to me that when it all went pear-shaped, he staggered into the cold streets of Copenhagen, found a warm bar, and got deeply, despairingly drunk. Me? I ask the wide-smiling flight attendant for a white wine, resisting the urge to ask for two. It’s a short flight.
As the aircraft thrusts into the sky (another 0.22 tonnes of CO2, according to my personal carbon-footprint calculator) I realise I have been fantasising, indulging in fairytales. Some part of me had expected that Copenhagen – and where better to write a happily-ever-after? – would mark the end of the beginning of the climate catastrophe, the end of inertia, and herald a new era of momentum, bravery, action, resolve. But instead the narrative wanders aimlessly in the deep, dark woods.
It all feels so crushingly clichéd and apocryphal. The brothers Grimm might have authored the archetypes. Politicians who can’t see beyond borders, backers or polls. Constituencies too distracted, too disengaged, too self-absorbed to empower leadership, or to imagine a future powered without fossil fuels. They make easy pickings for lobbyists peddling a mantra of doubt and denial, handsomely paid for their efforts by vested interests – most powerfully, coal and oil. All these have been conspiring to undermine the Copenhagen summit and, with a little help from the stolen correspondence of a handful of scientists, it seems they have succeeded.
To one who has heard and examined the scientific consensus over several years, Copenhagen’s failure brings a brutal end t
o any lingering belief that it will all be magically fixed. This is despite the weight and tenor of the scientific findings. Every day I log into the news streams that flow to my desk from around the world, scanning the reports, journals and science blogs for reassurance that maybe it is not so bad. Instead I find earnest, urgent scientific discussion paring back the once-comforting doubts and windy time frames, and veering into whole new paradigms of ugliness – talk of eco-system ‘surprises’ or ‘tipping points’, innocuous words enunciating scenarios of runaway climate change.
Scrutiny of climate tipping points – defined as the ‘critical threshold at which a tiny perturbation can qualitatively alter the state or development of a system’ – is still relatively young, but it is evolving fast. Tipping points include things like the melting of ice sheets as warm waters erode them from below; the bubbling up of methane hydrates, releasing potent greenhouse gases when warming opens their crypts under the sea floor; and the disabling of the powerhouse rhythms of winds, rains and currents on which nature turns and human civilisation is founded.
There’s the prickle of not unfamiliar dread, an echo of the feeling which loomed over teenager-hood in the 1970s, when the distant hostilities of Cold War protagonists would shift the hands of the Doomsday Clock another minute towards midnight, sending a brief shiver through populations of ordinary folk. At least it seemed there was bugger all we could do about that. And on many days there seemed a better than even chance that the worst might not happen.
Now the odds, scientists explain in disarmingly antiseptic language, are not so good. Ice-core data (primarily from Antarctica) tells us that for all of human history, atmospheric CO2 was around 275 parts per million (ppm) – that was until about 200 years ago, when civilisation began to dig up and burn coal to fuel the industrial age. Today the CO2 level recorded at the Mauna Loa Observatory in Hawaii – the longest record for direct atmospheric measurements – is nudging 390ppm, well over the 350ppm many scientists and some governments now identify as the ‘safe’ upper limit, and which was last seen around 1988. Turning the ship around will be some feat, one which gets harder with every passing day, though we are assured it’s not impossible, assuming there is the will to do it. Humans have already pumped out enough warming gases to commit the planet – by the end of this century – to temperature rises above the threshold for tipping points which are ‘potentially irreversible, and with unmanageable consequences’. We’ve put the planet on the slow burner, and now unseen forces may turn it up to a boil and we will be powerless to turn it back. This is the sober conclusion of a special investigation into the prospects of dangerous and dramatic climate ‘surprises’ published by the US National Academy of Sciences just as the advance parties headed to Copenhagen and I began the final countdown towards this flight south.