The Best Australian Science Writing 2015 (5 page)

One hundred trillion years from now, all the hydrogen of the universe will be exhausted so all remaining stars will die. In one hundred vigintillion years, quantum tunnelling will turn all matter left in the universe into liquid. In 10^10^120 years (in numbers too big for our minds to grasp, zeros are added in septillions), our universe will experience its heat death, encountering maximum entropy when there is no longer enough thermodynamic free energy to sustain processes that consume energy – like life.

By this point, time will have ceased to exist.

You can right now, if you like, float gently and lovingly over Earth and take in the view from the International Space Station. Anyone with an internet connection can get a lo-fi insight into what astronauts call the Overview Effect, the feeling of seeing the majesty of Earth from space and trying to take in the enormity of it and the tiny, unlikeliness of yourself.

You may find it pleasantly reassuring.

* * * * *

I know that I will have to tell Josh about this: that from everything I can find, Mars One doesn't appear in any way qualified to carry off the biggest, most complex, audacious and dangerous
exploration mission in human history. They don't have the money to do it. Summoning all the good faith I can muster, I wouldn't classify it as a scam, exactly – but it does seem an amazingly hubristic fantasy: an absolute faith in the free market, in technology, in the media and in money, to be able to do what thousands of highly qualified people in government agencies have so far not yet been able to do over decades of diligently trying, making slow headway through individually hard-won breakthroughs, working in relative anonymity. I will have to tell Josh that he shouldn't look to a theoretical future while his chance to be actually present in the privilege of human life passes him by; that he shouldn't give up on the hard work of making a life with the rest of us here on this horrendously messy, imperfect, unimaginably fragile and steadily warming Earth.

Late in the day, Josh and I are sitting across from each other, sunk in deep sofas that make us both look small. I ask Josh how he would feel if he made it through to selection, but Mars One didn't happen.

‘Disappointed,' he says quietly after a long moment. ‘Disappointed. But in the grand scheme of things, it's already done.'

For someone like Josh, it is a quest for true purpose, for belonging; a burning wish to be exceptional. ‘It's given me direction. It's given thousands of people direction.'

As I raise some of the most insurmountable problems with the mission – the lack of money, the lack of contracts, the fact that the selection panel isn't public – the rational Josh emerges. When I say that Chris Hadfield has serious reservations about Mars One, he isn't surprised; other astronauts have also expressed their scepticism. Especially that one he has always looked up to: Andy Thomas. ‘He hates it,' Josh says. ‘Absolutely hates it.'

Josh knows on some level that what Mars One is proposing is unlikely to come off. At least not in the time frame and budget it has set. But it's that most minute, most remote chance it could
actually work that keeps Josh holding on. That brought him home to Perth and away from a girl he loved, to dedicate all his energies to Mars One.

‘It's Joseph Campbell's
Hero With a Thousand Faces
,' he says, leaning forward. ‘Except you stay in the hall of heroes; you don't return with the boon. You're staying out there on the adventure, calling others to come.

‘That's why I'm willing to sign up to go one way.'

Job description

Uncharted waters

An uneasy alliance

The vanishing writers

Fiona McMillan

Start a blog, I told myself. Then you can write about anything you want.

The idea was enticing, but the possibility of writing about anything led very quickly to indecision and that led rather rapidly to no writing at all.

Galaxies, immune cells, archaeological digs, neurons, human behaviour, string theory. Where to begin? Specialise, they say, and there is indeed wisdom in that. But part of the fun of blogging, I felt, was the chance to explore, to tread new ground, to learn new things, to be amazed, puzzled, delighted, and to then share all of that.

I went for a walk to figure it out. On my way I saw a tree. I slowed. I stopped. I took a good look at this tree I'd passed many times before without so much as a glance. Standing there, it became quite clear that if you want to explore the entire universe, you can start quite close to home. This tree had a story. It had been, quite literally, scribbled all over. The markings were rough beneath my fingertips, the author nowhere to be seen.

A tale to decipher.

A decision made.

The universe starts here.

(Actually it does, by the way. The universe starts everywhere, so this is as good a place as any.)

So this is how the Luminous blog begins: with the story of a tree that took me more than 180 million years into the past.

Let me explain.

The eucalypts grow everywhere around here. This is Australia after all. This neighbourhood was carved out of bushland, and farmland that had once been bushland. But the creeks and the catchments were mostly left alone. There's a path that winds through. It's a little bit wild in there, a bit dangerous. It's marshy in some places, dry in others. Trees tower, some leaning precariously, ready to fall. The underbrush is dense and beautiful. Venomous snakes hide in the tall grass and bulbous spiders dangle patiently on expansive webs.

Some of the wildlife are more benign. There are rainbow lorikeets, kookaburras, and brush turkeys. Recently, I spied a wallaby. It regarded me for a moment then hopped away, almost dismissively. It's summer now, and the cicadas are singing. They chorus in perfectly synchronised waves, the crests of which are deafening. The sound thrums in your chest and drowns out the human world. The cicadas are here because they rather like the eucalyptus trees. And the eucalypts, in turn, have brought something else: tiny, elusive writers.

Australia is home to several hundred species of eucalypt. And it seems a modest variety make their home in this narrow stretch of wilderness. One of the most curious is the Scribbly Gum.

The name Scribbly Gum actually refers to a cluster of different eucalypt species found on the eastern seaboard of Australia. Their common signature, as it were, are the scribbles all over their pale, smooth-barked trunks. These markings have become something of a national icon, weaving their way into Australian folklore and literature.

The tiny writers are exquisitely shy, they leave their marks
and vanish. They're the elusive graffiti artists of the natural world. The work of beetles, was a common guess. Then in 1934 the culprit was identified: a moth, scarcely a few millimetres big. A specimen was sent to England into the care of a school teacher named Edward Meyrick. Meyrick himself was a curious entity. An amateur entomologist, he had a remarkable hobby of describing, naming, and cataloguing insect species. Moths were a particular favourite. Over his lifetime, he bestowed carefully thought out scientific names to more than 14 000 of them. And so, with due care, he named this one
Ogmograptis Scribula.
Literally,
the writer of the Ogam script.
It's said that he chose the name because the scribbles bore some resemblance to an ancient Celtic writing form called Ogam. There is also a second layer of meaning.
Ogmos
is not Celtic, it's Greek, and it means furrow – a groove or a narrow trench. When you look closely at the meandering lines on the scribbly gum, you'll see that's exactly what they are. To Meyrick, these strange patterns were unique. For all his expertise, his meticulous cataloguing of thousands of moth species, and his passion for taxonomy,
Ogmograptis
presented an enigma. Where it fitted with all the other families, genera and species of moths, he couldn't say.

And so the story of the diminutive creature remained unreadable for many years. This was exacerbated by the fact that they are difficult to capture in the wild. In defiance of the wide reputation of many moths,
Ogmograptis
is not lured by light. The larvae are equally recalcitrant. They are so dependent on the eucalypt, they're difficult to rear in captivity.

In the 1990s, CSIRO entomologist Ted Edwards AM suggested that the scribbles were formed by the larvae as they mined their way through the bark, feeding as they grew, zigzagging, then doubling back. Still the scribbles had never been quantified in detail. The math of these moths remained a secret.

Then a unique collaboration set the little moth's story on a
new course. Julia Cooke was a high school student who wanted to do a project on scribbly gum moths. Edwards had retired, but agreed to mentor Julia. So together they embarked on a study of the scribbles of three different species of eucalypt in the Canberra area. They measured everything they could. The height, the width, the length. The thickness of the furrow, the direction, the distribution. Were they on the north side of the tree, or the south? The east or the west? Were the paths random, or was there something more to it, an innate algorithm? How many zigs, how many zags?

No matter where the scribbles were found, they each showed three clear stages. ‘A' is the beginning, a very thin random scrawl that follows no rhyme or reason on any tree. ‘B' is the thicker, darker, zigzag, the tunnelling in earnest. ‘C' is the loop – they all do indeed make a U-turn and follow the path back to the start of ‘B'. And yet, there were distinct differences. In each of the three species of eucalypt they studied, there were slight variations, particularly in the length of the furrow and in the number of direction changes. It was as if these scribbles represented different dialects. A new theory emerged. There wasn't one species of scribbling moth, there were at least three, possibly more.

This finding inspired a new endeavour. This time the now retired Ted Edwards and other botanists and entomologists at CSIRO – including retired scientists Marianne Horak, Max Day AO and Celia Barlow – teamed up with geneticists and imaging specialists. Pairing field data with DNA analysis and scanning electron microscopy, they discovered that there are 14 different species of this tiny
Ogmograptis
moth, and that they can be divided into three distinct groups. They were also able to achieve what Meyrick had been unable to. They now knew how to classify it.

Their analysis, particularly the high-resolution images of the jaw, linked
Ogmograptis
with the Australian Tritymba moths and
the African Leucoedemia moths. Together they form the southern group of a larger family called
Bucculactricidae.
The implication of the African connection is profound – it suggests they share a common ancestor who lived on the supercontinent of Gondwana. In addition to this, the recent discovery of a eucalyptus fossil in South America contributes to strong evidence that eucalypts also have a Gondwanan origin. They seem to have thrived there, and where the eucalypts went the moths followed.

It's a hot day and I'm walking along the path with my young daughter. Over the song of the cicadas, I tell her to keep an eye out.
Smooth bark, not rough,
I say.
Look for the scribbles.

I see the tree first, but let her find it on her own. ‘There!' she calls out.

The tree is tall and covered in
Ogmograptis
graffiti. I cannot tell how far up they go, they disappear into the brightness of the day. There must be thousands of them. We take a good look at the ones right in front of us. My daughter reaches out, picks a scribble that she has decided is the best, traces its path. It follows the pattern perfectly. The random thin scrawl, like a languorous, drunken scratch. Then the regular zigzags, where the larvae grow larger, gnawing through the cork layer. This is why it doubles back. It doesn't just tunnel, it harvests. It's a neat trick: the first pass wounds the tree; as the tree repairs itself, it produces a scar tissue – tiny, thin-walled cells full of nutrients. The larvae then does its best 180 – some species have a tighter turning circle than others – and eats its way back again. When it's had its fill, it bores to the surface, finds its way to the base of the tree, pupates, emerges, and flies away. When the bark sheds, the scribbles are revealed.

* * * * *

Somewhere around 180 million years ago, during the Jurassic period, the Gondwanan supercontinent began to split. During this slow, tectonic tantrum Australia separated from Africa. Primates had not yet evolved. Dinosaurs roamed, and the world was still millions of years from the asteroid impact that would trigger their demise (well, not the demise of all of them, but that's another story).

Ogmograptis'
life cycle is annual, an evolutionary refinement in keeping with the yearly shedding of eucalyptus bark. The scribbles you see are this year's scribbles. It is feasible, then, that the scribble my daughter has traced is at least the 180 millionth generation. Arguably more.