by Chris Turney
The remaining expedition members immediately saw their scientific value. The geologist Griffith Taylor remarked that the ‘specimens brought back by the Polar Party from Mt. Buckley contain impressions of fossil plants of late Palaeozoic age, some of which a cursory inspection identifies as occurring in other parts of the world. When fully examined, they will assuredly prove to be of the highest geological importance’, while his colleague Frank Debenham argued that their preservation would allow people to ‘settle a long-standing controversy between geologists as to the nature of the former union between Antarctica and Australasia’. But what precisely the specimens were was not widely known.
Buckley Island—or Mount Buckley, as it is sometimes referred to—is a nunatak atop the Beardmore Glacier. It was here, on the return from the pole, that Edward Wilson found the coal deposits reported by Shackleton. The men spent the afternoon of 8 February 1912 and some of the following morning under the cliff face. Searching among the jumble of rocks they scanned the surface for samples, splitting promising-looking blocks of stone in the search for elusive fossils while the eagle-eyed Wilson made detailed notes. On close inspection some were found to contain the clear impression of ancient leaves.
Today these delicate samples are carefully preserved in London’s Natural History Museum, locked away in small cardboard boxes, hidden among a global collection that has been gathered over centuries. It is hard to believe these small rocks, several centimetres across and rough-edged, are the same ones that caught Wilson’s eye all those years ago. The scientist described them as ‘dark blackish slaty, shaly or coaly matter, some exceedingly hard, some splitting easily, and some breaking vertically into blocks’, where ‘the best leaf-impressions and the most obvious were in the rotten lumps of weathered coal which split up easily to sheaf-knife and hammer. Every layer of these gave abundant vegetable remains. Most of the bigger leaves were like beech leaves in shape and venation, in size a little smaller than British beech, and the venation were much more abundant and finer in character, but distinctly beech-like.’ The romance of their effort was not lost on Markham, who commented: ‘There is no more glorious and more touching event in the whole range of polar history.’
At the time of David’s 1914 talk in London, work on these fossils was nearing completion at the University of Cambridge. Working on the precious samples, Albert Seward, a professor of botany, reported in the first of several natural-history accounts from the expedition that some of the fossils were Glossopteris, the ubiquitous Gondwanaland flora that David had referred to in his Dunedin talk a decade before. Seward wrote: ‘the discovery of Glossopteris on the Buckley Island moraine supplies what is needed to bring hypothesis within the range of established fact.’
Here was proof that Antarctica had not only been warmer in the past: it had somehow been linked to South America, India and Australia at the centre of Gondwanaland. If the botanist Marie Stopes had been influential in encouraging Scott and his team to collect them after their heady night of dancing years before, it was serendipity indeed.
The simplest explanation for how Glossopteris came to be in Antarctica was through one of the hypothesised land bridges connecting the southern continents. In the oceans, however, the much-sought evidence had remained elusive. As part of the Australasian effort the expedition ship Aurora had made several vast sweeps of the Southern Ocean, taking soundings for water depth and trawling the sea for biological evidence of an ancient link. Even though Mawson was keen to find proof, he was not convinced by what they had found. The most promising was the Mill Rise, which Davis had discovered south of Tasmania, but this was an isolated plateau and did not span nearly enough of the ocean to make the case.
David did not give up on the idea of a land bridge, and contacted Teddy Evans and the crew of the Terra Nova about making depth soundings in a different sector of the ocean to the Australasian party. Shortly before the British set off to collect Scott and his men, David wrote to Evans: ‘King Edward Land and the land found by Amundsen and Lieutenant Shirase southwards from King Edward Land shows that the land probably consists of some very large and low islands, forming an almost continuous land mass, at the foot of the Antarctic Andes further south, in fact an island group analogous to that of the Palmer Archipelago and of the South Shetlands. There should be sunken islands to the north of King Edward VII Land and you might be lucky enough to locate some of these or the submarine Plateau on which they rest.’
He was convinced that ‘there is no part of the ocean more intensely interesting scientifically than that which lies between the South end of New Zealand and the Ross Sea.’ The measurements were made, but there was no sign of a land bridge there either. So how did Glossopteris come to be in Antarctica?
Bold new scientific ideas were coming to the fore as the Antarctic expeditions returned home. Alongside reports proving the existence of the atom and the discovery of a possible fossilised human species in England, a little-known German scientist called Alfred Wegener was suggesting something more controversial: the world’s continents formed part of an enormous jigsaw.
By 1912 Wegener was publishing scientific papers on his solution to the confusing observation that distinctive fossils were found across many continents. Later developed in a landmark book called The Origin of Continents and Oceans, his ideas were not published in English until 1924, delaying their discussion among the wider scientific community. Wegener proposed that you did not need drowned land bridges to account for similar geological formations in disparate locations. Instead, everything could be resolved if the continents had ploughed their way through the oceans—which Wegener described as displacement theory—changing their location on the surface.
Gondwanaland had been one massive supercontinent and, instead of parts sinking into the world’s oceans, it had split and the continents drifted apart from one another during the Jurassic period, which began around 161 million years ago. If the thinking was correct, it meant the Antarctic coal was no longer in the location where it had formed: Gondwanaland had torn apart and created the world we see today.
Not everyone in the scientific community welcomed this theory. Critics were scathing, largely because there was no evidence for how Wegener envisaged the continents moved across the surface. Comments such as ‘German pseudo-science’ and ‘purely fantastic’ indicate the depth of feeling. It was not until the 1960s that Wegener’s ideas became widely accepted, once it was recognised that it wasn’t the continents that moved per se but the plates on which they sit and float. Plate tectonics was able to explain how new continents and oceans were created, destroyed or rubbed along uncomfortably together.
Ironically, a focus of the Australasian effort, Macquarie Island, is now known to lie on the eastern boundary of the Indo-Australian Pacific Plate, explaining the frequent earthquakes experienced by Mawson’s men. It was not enough, however, to convince the Australian leader, who remained distinctly cold to the idea, though David did come round to the concept. More importantly, though, continental drift suddenly made it possible to argue that the Antarctic coal measures had formed in lower latitudes and then moved on. But was this the whole story?
During a long spell in our planet’s history, 299 to 251 million years ago, Glossopteris dominated the Gondwanan scenery. But it was not the only thing growing in the landscape. The diversity of Antarctic vegetation found alongside Glossopteris was relatively low, implying cooler conditions. More significantly, associated deposits were found to contain magnetic particles that sit close to vertical—the same principle behind dipping compasses—proving Antarctica was close to the magnetic pole at the time of Glossopteris and the formation of coal. It appeared that Antarctica had not been that far north, after all: at least, not far enough to avoid several months of twenty-four-hour darkness each year. And yet, given the large size of Glossopteris, it must have been relatively warm.
A strong clue to how this was so is provided by a remarkable living fossil, the Chinese deciduous tree ginkgo, or Ginkgo biloba. Fo
ssils of this plant have been found in Antarctic rocks dating back to the Cretaceous period, some one hundred million years ago. Although this was after the time of Glossopteris, we know greenhouse gas levels were at similarly high levels. Concentrations of air-breathing stomata on fossil leaves provide a first-order estimate of the amount of carbon dioxide in the atmosphere. The greater the concentration of gas, the more efficiently the plant photosynthesises and the fewer stomata it needs. By nourishing the plants at different levels of carbon dioxide the relationship can be quantified, and the results make fascinating reading. Compared to today’s level of 396 parts per million and rising, estimates for the time ginkgo was flourishing in Antarctica suggest it was around eight hundred parts per million. The Earth was in the grip of an extreme greenhouse effect.
The corresponding high temperatures meant there were no icecaps. Instead, the landscape was dominated by rainforest and inhabited by a wealth of wildlife. By growing ginkgo seedlings in blacked-out greenhouses with high levels of carbon dioxide, scientists at the University of Sheffield, in England, have been able to test whether the tree was capable of withstanding complete darkness for months on end. Although the ginkgo plants used up precious food reserves during winter, they could more than compensate for this by photosynthesising during the twenty-four hours of summer daylight. So long as carbon dioxide levels remained high, the forests of Antarctica could not only survive in the dark but thrive.
With the ceaseless shuffling of plates on the surface, Gondwanaland’s time was limited. Huge flows of lavas dating back to the Jurassic period are preserved within the Transantarctic Mountains, testament to the massive forces Alfred Wegener envisaged. By the late Cretaceous, some eighty million years ago, the last hanger-on, New Zealand, finally split from the West Antarctic. The supercontinent was no more. The rifting continues today: the Mount Erebus volcano in the Ross Sea is a visible sign of the process that began all those years ago. Satellite data collected since the 1980s shows how perceptive Wegener was. The crust still carries the physical scarring that marks the break-up of Gondwanaland, and the links between Antarctica and the other southern continents. It is a spectacular confirmation of the German’s idea of a ‘flight from the poles’.
The end of Gondwanaland had global repercussions. The opening up of the Drake Passage and Scotia Sea around thirty million years ago brought one of the world’s great ocean currents, the Antarctic Circumpolar Current, into being. Although this Antarctic current sustains abundant life in the Southern Ocean—including South Georgia and other subantarctic islands—it isolated the southern continent from the rest of the planet. Temperatures in Antarctica dropped precipitously and the vast ice sheets we see today began to grow. With the accompanying cooling there were massive evolutionary changes. For those left behind on the keystone continent of Gondwanaland, the future would prove considerably challenging.
The scientists of 1912 were only just starting to grapple with some of these issues. Although Wilson got the primitiveness of emperor penguins wrong, he was correct in thinking that they offer a significant insight into the origin of modern birds. With the discovery in 1953 of deoxyribonucleic acid—usually shortened to DNA—scientists realised that the evolution of species is accompanied by changes in their genetic make-up. When two species arise from a common ancestor and go off on their own evolutionary pathways, differences in DNA accumulate. The changes in the genetic composition of a species are like the hands of a clock, each change equating to the tick of a molecular timepiece. These accumulating ticks can be used to calculate when a species evolved. The critical thing is to find out the rate at which genetic mutations take place.
This is where penguins come in. Penguins have arguably the best fossil record of modern birds around the Cretaceous–Tertiary boundary, sixty-five million years ago, a period best known for the extinction of the dinosaurs. The earliest fossil penguin evidence has been found in New Zealand, and dates back sixty-two million years, shortly—geologically speaking—after the separation of Gondwanaland. These early fossils provide an important fixed point in time, not just for calibrating the rate of changes in penguins but across the whole genetic tree of birds, allowing major junctures to be dated.
The results are fascinating, not least because the popular early theory that penguins evolved from the extinction of the dinosaurs is wrong. There almost certainly was a dinosaur relative to birds. However, the genetic code shows that modern birds had a last common ancestor long before the end of the Cretaceous, with penguins separating from their next nearest living relative, the stork, around seventy-one million years ago—long before dinosaurs became extinct. As Antarctica became cloaked in ice, species of penguins moved out along the circumpolar current to the subantarctic islands, and from there to other southern landmasses, reaching as far north as the Galapagos Islands a trifling four million years ago. For the penguins that stayed behind, the continent became a lot quieter.
After the exploration work of 1912 Antarctica went from being an inaccessible land described in fantastical stories to being part of the real world. Before, the information gleaned had been sporadic. Now there were careful observations and hard data. A common misconception—as pervasive as the tall tales—that Antarctica was just a land of white nothingness had been disproved, and with this the world’s perception changed irrevocably. The southern continent was a staggeringly complex landscape—and now there were more questions than answers. The expeditions of 1912 had shown the way, and it was only the beginning of the scientific work.
The Times reported:
Now that the South Pole has been reached geographers will be free to carry on the investigations of this huge continent without any unpleasant element of rivalry, such as has existed hitherto in both ends of the earth. The expedition which started last year from Australia under Dr Mawson is the type of expedition that is to be encouraged in the future; and it is to be hoped that Dr Mawson’s example will be followed by other explorers until the whole contour of this Antarctic Continent is mapped and such knowledge of its geographical, meteorological, biological and other conditions acquired as will satisfy the demands of science.
Mawson and Scott inspired fierce loyalty. From their efforts there emerged scientists dedicated to Antarctic affairs, who established research organisations and institutions that persist today. Debenham and Priestley helped found the British Scott Polar Research Institute in 1920; in Australia, Mawson succeeded in establishing the Australian National Antarctic Research Expeditions, the forerunner of today’s Australian Antarctic Division.
This enthusiasm for the south extended to protecting the continent itself, through the Antarctic Treaty. Enacted in 1961, this international agreement is now supported by forty-five signatories, and puts all territorial claims south of 60° on hold while preserving a nuclear- and mining-free Antarctic for future generations. The continent is now dedicated to science and exploration—a fitting tribute to those who undertook pioneering work and lost their lives on the ice.
By the first decade of the twentieth century rapid industrialisation was engendering a new form of confidence. The romance of civilised explorers battling against brute nature to unearth its hidden secrets captured a collective mood. And it was not entirely positive: this new swagger found articulation in the global power game of World War I.
The scientific explorations of 1912 proved an inspiration for the European youth of the day. Tales of ripping yarns and daring feats preached the value of self-sacrifice for the greater good. Poems drawing comparisons between the conflicts at Gallipoli and Flanders with the expeditions in Antarctica became widely known, while Ponting’s original film of Scott’s expedition, The Great White Silence, was shown to more than one hundred thousand officers and men of the British Army, with the photographer lecturing daily in London through most of 1914. The British tragedy in Antarctica struck a poignant note.
World War I resulted in the deaths of tens of millions of soldiers and civilians. Within these statistics lie the men to
whom Shackleton dedicated his book South: those ‘who fell in the white warfare of the south and on the red fields of France and Flanders’. The Japanese declared for the Allies but it does not appear any of Shirase’s men died during the fighting, while Norway remained neutral.
Of the other expeditions, however, one in ten of those who had served in and survived the extremes of the Antarctic did not live to see 1919. Many were mentioned in dispatches. Filchner’s expedition lost two men to the war and Scott’s three, while Mawson’s two team members included Robert Bage who, after surviving a second winter in Antarctica, died during the first fortnight of the Australian campaign at Gallipoli. It was a terrible waste of life.
And it wasn’t just men who were victims. The war suddenly created a large market for explosives—in particular, glycerine, a by-product of whale-oil production. Antarctica’s natural resources were tapped, ensuring the continent joined the modern world.
The first meeting of the British Association for the Advancement of Science in Australia was held on the verge of the conflict, in August 1914. The German scientist Friedrich Albert Penck was en route when war was declared. David defended Penck in the same way he had Shirase and his men in Sydney, speaking highly of the German and vouching for him while in Australia. The sentiment was not reciprocated; it seems Penck did spy for Germany during his visit, taking photos of harbour defences in the New South Wales city of Newcastle.
David went on to volunteer for the war effort, though he was fifty-eight, and became a major in the Australian Mining Corps—better known as The Tunnellers—which he helped establish; his geological expertise proved crucial to the Allies efforts, most notably at the Battle of Messines in 1917, for which he later received the Distinguished Service Order. It was yet another remarkable achievement in a remarkable career.