by Tim Flannery
The origin of the kangaroos was very much on my mind when, in late 1984, I got my first real job. Following my doctorate I had been appointed to the mammal section of the Australian Museum in Sydney, and a phone call from Dr Alex Ritchie, curator of fossils, soon brought an exciting discovery. ‘There’s something here you really must see,’ he blurted out in his brogue, before giving me the address of a nearby motel. Alex opened the door to reveal a suntanned opal miner and, behind him, spread out over the bed, were hundreds of opal fossils.
In opal fossils we see nature’s rubbish transformed into precious gems. No one fully understands how a shell, piece of wood or bone is turned into opal, but such fossils are found only in a few locations in New South Wales and South Australia. At these special sites, miners dig into sediments that were laid down in or beside the inland sea, and at depths of up to twenty metres they find shells, dinosaur bones and other fossils that flash with red, green and blue. The opal fossils on the bed had been brought to the museum for sale, and among the usual clamshells, fragments of turtle carapace and other bones, one stood out.
It was a jawbone that had once belonged to a creature the size of a cat, and it still bore three teeth. It was a magnificent specimen—as much a jewel as a scientific treasure, for through the flashes of opalescence that emanated from it one could see the internal structure of the bone, which seemed to have been replaced by a beautifully tinted glass. Through this the roots of the teeth and the channels that once conducted nerves and blood vessels could be seen. It was as if, after being buried, the entire bone had been delicately etched away, leaving a void into which the opal had been deposited. Yet so delicate was the process that even fine films of clay, such as those surrounding the tooth roots, were left in place as the opal formed around them.
The jaw represented a breakthrough, for it was around 110 million years old—four times as old as any mammal ever discovered in Australia. But what sort of mammal was it? I had half-expected the bone to be from an ancient marsupial—perhaps a distant relative of the kangaroo—but it was in fact the fossil jaw of an ancient platypus. In 1985 the jaw, along with other opalised fossils, was purchased by the Australian Museum for $80,000. The news caused quite a stir among the opal miners at Lightning Ridge and I hoped that more fossils would be forthcoming. Within days I received a phonecall from an old miner who announced in a conspiratorial whisper that he had located the complete skeleton of a ten-metre-long dinosaur on his claim. Such a specimen, if preserved in opal, would be one of the most important fossils ever found, and would be worth millions of dollars. I was thrilled at this news and was mentally making arrangements for an impromptu trip out west when he said, ‘Yep, I’ve outlined him perfectly on the surface with stones.’ After some probing it emerged that the ‘skeleton’ was still buried fifteen metres underground, and divining its presence had been quite a business. The caller told me that he had been left in charge of his son’s electrical store, who had urgent business interstate. This unprecedented opportunity had allowed the old tinkerer to construct a fossil-detecting apparatus consisting of a large head-frame surrounded by magnets and an electrical current supplied by an array of batteries. The maker of this outlandish device had wandered the scrub for days before making his grand discovery.
Some scepticism must have crept into my voice because the caller suddenly volunteered, ‘I can find out anything with this machine, you know. I can tell yer how much money yer have in yer wallet right now!’
Seizing on this assertion, and remembering that I had not been to the bank, I asked, ‘All right, how much is in it then?’
After several minutes fumbling he replied, ‘Son, the signal’s too weak from here. Better if you come out and look at the dinosaur, and then I’ll tell yer.’
A decade later, in 1994, another opalised mammal jaw was unearthed in the area, providing a plausible excuse for a visit to Lightning Ridge. This second jaw, which was also around 110 million years old, had molars that resembled miniature hot-cross buns. After exhaustive comparisons I concluded that it too had belonged to a platypus-like creature, but one adapted to eating hard-shelled food such as clams. Perhaps it was Australia’s answer to the sea otter, although pre-dating that creature by 100 million years.
The specimen had been found by a schoolteacher who spent his spare time chasing opal underground. He had been careful to recover any fossils he found during his work, and was happy for me to visit him. His camp was an eye-opener to the miner’s way of life, consisting of no more than a few swags and utensils around a large fire. Underground, though, was a different story. The shaft leading to the opal-bearing layer was only a metre wide, and a long series of rusting, linked ladders, disappearing into the gloom, hung from one side. After descending around twenty metres the shaft opened out into a spacious cavern where a digging machine, blower and electrical cables lay.
All around the walls I could see mud from the margin of the inland sea, with ripple marks and tiny channels still intact, and here and there the dull glint of opal. This was where the fossil had been unearthed. The teacher had spotted it in the wall of the mine when he and another man were clearing away clay with a jackhammer. The teacher had shouted for his mate to turn off the hammer to avoid damaging the specimen: his mate refused. He was there to dig opal, not fossils, he said, as he pointed the hammer at the priceless relic. After a brief tussle the teacher grabbed the specimen from the wall, snapping off both ends in the process. As a result we may never know if the creature had a bill like a living platypus, or just how the jaw articulated with the skull.
For every precious fossil recovered at Lightning Ridge ten thousand must be lost to the digging machines and the tumblers that wash the opal dirt, in the process rolling priceless fossils of unknown creatures to nubbins.
By 2001 my hopes of finding dinosaur-age ancestors of the kangaroos had all but vanished. So when a chance arose to pierce to the heart of the inland sea I travelled with different motives. I was by this time director of the South Australian Museum in Adelaide and was preparing for a new exhibition of opalised fossils. The mayor of Coober Pedy, the leading opal-mining town in Australia, some 1300 kilometres west of Lightning Ridge, had invited me to participate in their inaugural opal festival. It was an opportunity too good to miss as miners from across Australia were expected to attend.
The drive from Adelaide to Coober Pedy takes about nine hours and crosses a stark transect from Australia’s green fringe to its dead heart. The stately river red gums and winter-green croplands drop away after Port Augusta, then mulga gives way to a scattering of saltbush. As one approaches Coober Pedy even this thin cover exhausts itself and all that is left is a panorama of broken rocks and blowing dust known as the Moon Plain. Once the floor of the inland sea, it is still littered with the debris of that past age and is a mecca for palaeontologists. Coober Pedy supposedly means ‘white fellow in a hole’, and most residents live underground—the only sensible thing to do in such a place. The quality of the dwellings varies enormously; some are palatial, while others are but a drive in the side of a hill whose entrance is draped with a piece of burlap, which when swept aside reveals a dusty swag and a caravan stove. Some of the more basic homes are located far out in the distant opal fields, and when enjoying the hospitality of a miner living in such circumstances, I often wonder how they survive through the summer when for weeks on end the thermometer refuses to dive below the old century Fahrenheit mark. Fate can play cruel tricks on such men. One resident showed me where he had discovered $20,000 worth of opalised shells when enlarging his bedroom. He had been sleeping for decades with his head just inches away from the cache, often desperate for a dollar or two for food.
I had travelled to Coober Pedy with Ben Kear, a doctoral student who was studying the reptilian giants that thrived in Australia’s ancient inland sea. He told me the stones that lay strewn so thick across the Moon Plain had come from far and wide—some as far afield as Cobar, while others hailed from the Gawler Ranges and Broken Hill, hu
ndreds of kilometres to the south and east. How had they got here? Some, it transpired, bore unmistakable evidence of transport by ice. The inland sea that in my imagination was a tropical paradise, was at times a field of icebergs spawned from great glaciers that ringed its southern margin. One hundred and twenty million years ago Coober Pedy was almost over the South Pole—a strange fate you might think for a place destined to lie at the baking heart of Australia.
As part of the festival, Ben and I had offered to conduct a fossil identification workshop for miners. Most specimens brought in were of limited palaeontological interest—opalised driftwood mostly, from the stunted forests that grew around the inland sea. A few very important specimens, however, did turn up, among them a magnificent vertebral column of an ichthyosaur preserved in precious opal. The specimen was famous across Australia’s opal fields, and I was delighted when the miner offered to lend it to the South Australian Museum. He said that ever since he had migrated from Croatia many years ago, Australia had been good to him and he wanted to give something back.
It became obvious that some of the miners had a ‘colourful’ past. Many were known only by their Christian name or nickname, and with the coming of the goods and services tax (GST) they were feeling uncomfortable. A representative of the Australian Taxation Office was present at the festival to explain this new tax. To a packed house he stated that, by virtue of their driver’s licence, passport or vehicle registration, they were all known to the government. It was no use trying to hide, for the taxman would find them, wherever they were. In response to this chilling news one opal buyer stood and said that he supposed it was all right to record his customers by the names they gave him, for he had purchased $200,000 worth of opal from Adolf Hitler last week, and $250,000 from Attila the Hun the week before that. The tax man was not fazed, replying simply that where ‘reasonable suspicion existed’ the buyer was duty-bound to record Mr Hitler’s car registration number and pass it on to the tax office. A sustained silence reigned thereafter, during which an old miner sitting next to me whispered, ‘There’s many an uncapped shaft around here. That bastard will be lucky to get out of town alive!’
The next day an elderly miner arrived at our workshop. From the tips of his shoes to the end of his long scraggly beard he was stained the orange colour of desert dust, and he glanced around conspiratorially before delving into his pocket to retrieve a small vial of water, such as miners keep their treasures in. ‘What do you make of this?’ he said as he slipped it into my hand. Peer as I might I could make out nothing in the liquid but a few specks of dust. After a prolonged silence he said, very deliberately, ‘It’s an opalised worm jaw, and the last time I showed it to anyone they offered me five thousand dollars for it. How much will the museum pay?’ The old fellow looked excitable, and I feared making an insulting offer.
‘Well, it’s a fascinating specimen,’ I said, sucking my teeth and buying time. ‘The opal value must be quite extraordinary—five thousand dollars at least—but our interest is fossils, and the fossil value of this particular worm’s jaw is limited.’
Without a moment’s hesitation the miner snatched back his precious vial and, glaring at me, slunk away.
My only official duty was to greet the opal festival parade as it arrived at the showground, and kiss the opal queen. My first glimpse of that august person came at 8 am—the mercury rising sharply—atop an enormous flatbed truck that ground its way at walking pace up the main street towards the showgrounds. She was a lady of generous proportions, resplendent in fishnet stockings, very short miniskirt, low-cut blouse and silver tiara. Her throne was an aged couch short on stuffing, and exposing several springs. Then came the drag-racing fraternity, whose display consisted of a defunct dragster that had been set alight, which was towed by an only slightly less disreputable vehicle. The fire brigade followed, playing their hoses wherever things seemed to be getting too hot. Most of the town brought up the rear, led by ‘Bad and Ugly’ a pair of identically dressed humans of indeterminate sex wearing brown paper bags over their heads and on which their names were written in texta. As the procession spilled into the showground it disrupted the beer-belly competition; the contestants, even at the last minute, were desperately trying to put on form.
There were camel rides, sideshows and an opal booth. The place was packed, including many Aborigines from outlying settlements. It seemed that everyone was wearing a broad-brimmed hat, moleskin trousers and R. M. Williams boots. And it was there, in that great melting pot, where a goodly contingent of people from nowhere mixed with Croatian miners, Greeks, Italians and indigenes, that I declared the festival open; but everyone was having far too good a time to take notice of anything I said.
I enjoyed immensely my work with the opal miners, but as far as the evolution of kangaroos went, my work in Queensland, Lightning Ridge and Coober Pedy had turned up no leads. It was in more recent sediments, preserved in other regions and dating to the last 30 million years, that answers would be found.
Land of Giants
2004
IN 1873 THE famous nineteenth-century anatomist Sir Richard Owen, then director of the British Museum of Natural History in London, described a massive jawbone that had been unearthed beside the Tambo River in eastern Victoria. Although the creature would have been the size of an ox, Owen was convinced it had once belonged to a kangaroo and had accordingly named it Palorchestes azeal, meaning ‘ancient leaper’.
Few dared query such an authority and around 1958 Harold Fletcher, the curator of fossils at the Australian Museum in Sydney, decided to give the public some idea of what Palorchestes looked like. Taking a grey kangaroo for his model, he had a commanding reconstruction made. Towering more than three metres, the monstrous plaster figure was for a short time a great drawcard and object of awe. Yet it was fated to come to a bad end, for a few months after it went on display, Jack Woods, director of the Queensland Museum, took a closer look at the jaw of Palorchestes and discovered that it lacked the distinctive hole through which the chewing muscles pass in all kangaroos.
Palorchestes was in fact a distant cousin of the wombat, a revelation that so filled the museum staff with embarrassment that they took to their creation with a sledgehammer. Moral: don’t believe everything you see in a museum—or on TV, for that matter. Yet giant kangaroos did once bound over Australia’s inland plains, and though none were as large as the Australian Museum’s fantastic plaster model, some were far more unusual.
Australia’s ice-age kangaroos have fascinated me ever since that first opportunity in 1974 to clean and study their skeletons as a museum volunteer. In 1978 a special chance to study them arose when Tom Rich found himself with so many volunteers at Hamilton that there was insufficient room for all to work. To ease the congestion, Tom gave permission for two to accompany me to a fossil deposit I had located near Minhamite, eighty kilometres east of Hamilton. There, fossilised bones are preserved in a deposit of thick black clay on the bank of a small creek. Although it was ‘only’ tens of thousands rather than millions of years old, I was excited by the deposits because they contained the remains of many gigantic kangaroos.
To sit in the mud on a frigid summer day such as Victoria’s Western District can offer, slicing through stiff clay with a trowel and encountering massive mahogany-coloured bones, became the most exhilarating experience of my life—something I could only be driven from by horizontal sleet, thence to huddle in the back of a panel van to warm myself as the slurry swirled all about. To flick a triangle of clay from such a bone, revealing its shape and knowing that you are the first living being in 50,000 years to see that sight, was as energising as sex; for then you could visualise the part of the skeleton that the bone represented, and fantasise about the kind of marsupial from which it came.
Sometimes, intimate insights into the life and death of an animal would become evident: the slice-mark made by the tooth of a marsupial lion (imagine seeing the groove where that great slavering premolar found its mark), or an old fracture
that had healed—each one as informative as the scar on the body of a lover. But what held me most in thrall was trying to imagine those animals as they really were. A huge grey kangaroo, almost twice the weight and a third taller than any living today had stood on this spot. Did it endure the sleet as I did? Did its nostrils flare at the scent of its mate; and how did it breathe its last, right here, in the black clay under my feet?
I was holding its anklebone in my hand 50,000 years after its burial, a still-living thing on its land, yet separated from its life by such a gulf of extinction and change as might separate me from my unimaginably distant descendants, if humanity and my genes survive so long. The gulf of time will consume you if you linger over it too long—it will break down your morality and your essence, so that you, like the extinct kangaroo, will only fuck and eat and sleep, until you too join the black mud.
And what of the extinct giant wallaby whose empty eye-socket looked out at me as I excavated its skull a short time later? What land did it behold, and what were its comforts? We need not only more scientists but poets as well—a Ted Hughes of palaeontology—who can imagine those past lives and guide us through the labyrinth of time to show us how things were in the distant past.
The story of the Australian ice age—the most glorious age of kangaroos—was first glimpsed in caves located a few kilometres east of Wellington, New South Wales, where the western foothills of the Great Dividing Range give way to featureless plains. As with Hamilton and Bow Creek, the Wellington Caves lie in a region of undulating hills and red-gum-dotted grasslands. Their secret was first penetrated around 1829 when a settler named George Rankin lowered himself into a shaft on a long rope that he had attached to a protrusion on the cave wall. When it unexpectedly snapped off he discovered it to be the limestone-encrusted leg bone of a huge, extinct bird. It was the first significant ice-age fossil ever found in Australia, and it led to explorations that revealed the caves to be chock-a-block with the bones of extinct creatures. So abundant are these fossils that they were once mined for their phosphate content, a process that saw millions crushed to dust and strewn on the fields as fertiliser. For all the destruction this entailed, a huge number of fossils made their way into museum collections.