Chapter Content
**Chapter Title: The Frozen Embrace**
*“I had a dream, which was not all a dream.
The bright sun was extinguish’d, and the stars
Did wander darkling in the eternal space…”*
*― Lord Byron, “Darkness”*
The year was 1815. On the Indonesian isle of Sumbawa, Mount Tambora, a volcano beautiful in its seeming dormancy, erupted with a ferocity unseen in living memory. Molten rock spewed skyward, tidal waves surged, and ultimately, an estimated 100,000 lives were claimed. This was an eruption beyond the scale of recent human experience – the most violent in ten millennia, dwarfing the 1980 blast of Mount St. Helens by a factor of fifteen, its power equivalent to sixty thousand Hiroshima-sized atomic explosions.
News traveled slowly in those days. Seven months passed before a brief report – essentially a merchant’s dispatch – appeared in the *London Times*. But the effects of Tambora’s fury were already being felt. A quarter of a trillion cubic meters of ash and dust choked the atmosphere, dimming sunlight and dropping global temperatures. The sunsets became eerily, morbidly beautiful, captured with unsettling vibrancy by the British painter J.M.W. Turner. Yet more often, people simply lived under a pall of oppressive twilight. This dreadful gloom inspired Lord Byron's somber verses that head this chapter.
Spring faltered, summer offered no warmth. The year 1816 became known as "The Year Without a Summer." Crop failures were widespread. In Ireland, famine and typhus claimed 65,000 souls. In New England, it was dubbed "Eighteen Hundred and Froze to Death." Frost persisted into June, preventing seeds from germinating. Livestock, deprived of fodder, perished in droves or were prematurely slaughtered. By any measure, 1816 was a catastrophic year – arguably the worst single-year agricultural disaster faced by modern farmers. Globally, however, temperatures dipped by less than a degree Celsius. What this revealed was the startling fragility of the Earth’s natural thermostat.
The 19th century was, in itself, hardly a warm period. For the preceding two centuries, Europe and North America had been locked in what we now recognize as a “Little Ice Age." This allowed for fantastical displays of ice skating on frozen rivers, along the canals of the Netherlands that now, are but a distant memory. In essence, it was an epoch where coldness was the accepted norm. This makes it easier to understand why 19th-century geologists struggled to grasp that they inhabited a relatively mild world compared to eras when glaciers sculpted vast landscapes and frosts annihilated the prospect of winter carnivals.
They knew something unusual had occurred in the past. Baffling anomalies were scattered across the European landscape: the skeletal remains of arctic reindeer found in southern France, colossal boulders perched precariously where they seemingly didn't belong. Such findings led to audacious, albeit often preposterous, explanations. A French naturalist named De Luc attempted to explain the presence of massive granite blocks atop higher limestone layers in the Jura Mountains by suggesting that trapped air within caverns had launched them upward like corks from a popgun. While hardly plausible for moving such weighty objects across such distances, 19th-century scientific inquiry often prioritized internal consistency over empirical evidence.
Arthur Hallam, a prominent British geologist, observed that had James Hutton, the father of 18th-century geology, personally examined the Swiss landscape, the fractured valleys, the smooth striated surfaces, the moraines of debris left by retreating rocks, and other clues that might be apparent to an observer, he would have instantly comprehended the significance. All that evidence pointed towards the passage of massive ice sheets. Unfortunately, Hutton was no traveler. However, based even on second-hand accounts, he readily rejected the idea that vast floods had hurled these huge rocks up thousand-meter slopes – he pointed out that there was no water on earth that would float a rock. Therefore, he was among the first to suggest large scale glacial action. Yet his theories failed to catch on, for half a century most naturalists insisted that the marks on the rocks could be explained by wagon wheels and perhaps, hobnails from boots.
Conversely, local farmers, unburdened by established scientific doctrine, often understood more. Swiss naturalist Jean de Charpentier recounted a story of walking a country lane in 1834 with a Swiss lumberjack, idly discussing the scattered boulders along the path. The lumberjack matter-of-factly stated that these rocks originated in the Grimsel region, far to the east. "When I asked him," Charpentier wrote, "how these rocks arrived in his area, he answered without hesitation: 'The Grimsel glacier carried them here, because that glacier once extended all the way to Bern.'"
Charpentier was elated, as he himself had reached similar conclusions. But when he presented his views at scientific gatherings, they were met with scorn. Charpentier’s closest companion, a Swiss naturalist named Louis Agassiz, initially dismissed the theory but slowly became convinced and then enthusiastically championed it.
Agassiz, a former student of Cuvier in Paris, held a professorship in natural history at the Academy of Neuchâtel. Another friend, Karl Schimper, a botanist, actually coined the term "Ice Age" (*Eizeit* in German) in 1837. He argued that the evidence pointed to ice sheets not only covering the Swiss Alps, but also vast swathes of Europe, Asia, and North America. This was a radical concept. He loaned his notes to Agassiz – a decision he would later regret, as Agassiz increasingly claimed the theory as his own, leaving Schimper feeling justly deprived of credit. Charpentier, too, eventually became estranged from his old friend. Alexander von Humboldt, a friend of Agassiz, famously described the three stages of scientific discovery: first, people deny that it's true; then, they deny that it's important; finally, they credit the wrong person. When Humboldt made this observation, Agassiz was very much on his mind.
Regardless, Agassiz dedicated himself to the cause. He ventured where needed to grasp the impact of glaciers, he descended into treacherous crevasses, scaled daunting Alpine peaks, often seemingly oblivious that he and his team were summiting mountains previously unclimbed by humankind. But almost everywhere Agassiz went, his theories were met with skepticism. Humboldt urged him to abandon his obsessive glacial explorations and return to the less controversial study of fossil fish. However, Agassiz was a man driven by an idea.
In Britain, support for Agassiz was even scarcer, since most naturalists had never even seen a glacier and struggled to grasp its immense power. "Are scratches and polished surfaces on rock formations to be attributed solely to the action of glaciers?" Roderick Murchison asked at one meeting in a derisive tone, seemingly convinced that the rock surfaces were caused by a light glaze of frost. Even until his death, he remained intensely mistrustful of those "glacial maniac" geologists who ascribed everything to ice. William Hopkins, the leader of the Geological Society and a professor at Cambridge, agreed. He declared the "glacial transport of rock seems mechanically absurd" and beneath the consideration of a scientific institution.
Undeterred, Agassiz tirelessly traveled and lectured, proselytizing his theory. In 1840, he presented a paper at a meeting of the British Association for the Advancement of Science in Glasgow, only to be publicly refuted by the great Charles Lyell. The following year, the Geological Society of Edinburgh passed a resolution conceding that there might be some merit in Agassiz's theory, but certainly not as applied to Scotland.
Lyell eventually experienced a change of heart. His epiphany came when he suddenly recognized that a moraine near his Scottish estate – a long ridge of rock he'd passed countless times – could only be explained by glacial deposition. Despite this internal shift, Lyell lacked the courage to publicly endorse the Ice Age theory. It was a difficult period for Agassiz. His marriage collapsed, Schimper denounced him for plagiarizing his research, Charpentier ceased speaking to him, and Lyell, the most influential geologist of the era, offered only lukewarm, equivocal support, even though he was beginning to be a convert to the glacier theory.
In 1846, Agassiz accepted a lecture tour in the United States, where he finally found the recognition he craved. Harvard University offered him a professorship and built him a state-of-the-art museum of comparative zoology. His settling in New England undoubtedly helped his cause, as the long winters cultivated a certain sympathy for theories about extended periods of cold. Six years later, Agassiz made his first scientific expedition to Greenland. This was also crucial. They discovered that almost the entire island was covered by an ice sheet, much like the ancient ice sheets Agassiz theorized of. His theory finally began to gain true momentum. The glaring weakness with Agassiz's hypothesis was that he couldn’t provide an explanation for the trigger of the Ice Ages. However, help arrived from an unexpected source.
In the 1860s, British newspapers and academic journals began receiving articles on hydrostatics, electricity, and other subjects, written by James Croll of Anderson’s University in Glasgow. One article, published in *Philosophical Magazine* in 1864, suggested that variations in Earth’s orbit were likely the cause of glacial periods. It was lauded as a piece of scholarship of the highest level. So imagine the surprise, perhaps even embarrassment, when it came out that Croll was not a faculty member, but a mere employee.
Born in 1821 to a humble family, Croll's formal education had ceased at age thirteen. He had worked in a variety of trades – carpenter, insurance salesman, keeper of a temperance hotel – before landing a job as a janitor at Anderson's University (now the University of Strathclyde) in Glasgow. He convinced his younger brother to take on the majority of his responsibilities, this allowed him to spend quiet evenings in the University library, educating himself in physics, mathematics, astronomy, hydrostatics, and other emerging disciplines. Slowly, he started writing a series of papers, focused mainly on the movements of the earth and their effect on the climate.
Croll was the first to propose that the periodic shift in Earth’s orbit from elliptical (that is, somewhat egg-shaped) to nearly circular and back again could drive glacial cycles. Before him, no one had attempted to explain Earth's weather patterns with an astronomical aspect. Thanks to Croll’s convincing theories, people began to accept that the Earth had previously seen areas dominated by ice. Croll's genius was broadly acknowledged, as he got a place at the Geological Survey of Scotland and he received various awards: London Royal Society and the New York Academy of Science were keen to have him, and the University of St Andrews gave him an honorary degree, to name but a few.
Sadly, even as Agassiz's theories were finally being embraced in Europe, he was off on field expeditions in some of the most untamed and barely researched corners of the Americas. Wherever he traveled, including near the equator, he found signs of past glaciation. Eventually, he became convinced that ice had once covered the entire planet, obliterating all life that God had previously created. The evidence Agassiz cited did not support such claims. Nevertheless, he rose in stature in his adopted homeland to something approaching sainthood, so much so that upon his death in 1873, Harvard University deemed it necessary to appoint three professors to replace him.
But Agassiz’s theories quickly fell out of favor. This can happen with time. Less than ten years after his death, the head of the geology department at Harvard, wrote that, "the so-called Ice Age...a few years ago so popular among geologists researching glaciers, but now it is seen for what it is, and geologists would happily abandon this idea."
In part, the issue was that Croll's calculations placed the last glacial period 80,000 years ago, but the geological evidence increasingly suggested that the Earth had experienced major disturbances far more recently than that. Without a credible explanation for what initiated a glacial period, the entire theory floundered. This problem would remain for some time before a Serbian scholar named Milutin Milankovitch would come along. Milankovitch had no background in the study of celestial movements - he was a trained mechanical engineer - but he suddenly found himself drawn to the question in the early 20th Century. He realized that the trouble with Croll’s theory wasn't that it was incorrect, but that it was too simplistic.
As Earth travels through space, not only does its orbital length and shape change, but so does its angle of tilt towards the sun, which is known as its obliquity, and its eccentricity. These changes occur in a regular fashion, all impacting the length and strength of sunlight that falls on any given point on the planet. In particular, the Earth experiences three positioning changes over long durations of time, which are referred to as axial procession, procession, and eccentricity. Milankovitch thought that these complex cyclical variations might be linked to the appearance and disappearance of Ice Ages. The problem was that these cyclical fluctuations varied so greatly in timescale – some around 20,000 years, others 40,000 years, and even some 100,000 years, and the change to each of the cycles could vary by thousands of years. This meant working out the intersection of all these factors for any period would require an almost endless number of elaborate calculations. Critically, Milankovitch had to calculate how the three factors changed over a million years, the angle and duration of the sunlight hitting every single latitude on Earth in every season.
Happily, such a sprawling, complex undertaking suited Milankovitch's nature. For the next 20 years, even when on vacation, Milankovitch tirelessly calculated his tables with pencil and slide rule – a task that could now be completed by a computer in a day or two. The calculations had to be undertaken in Milankovitch's free time, but in 1914 Milankovitch suddenly found himself with much more time. The First World War broke out, and he was arrested as a reservist in the Serbian army. For much of the subsequent four years, he was confined to Budapest with loose controls, only having to report to the police on a weekly basis. This left him to work diligently in the library of the Hungarian Academy of Science. He was, perhaps, the happiest prisoner of war in history.
The fruits of his labor were published in 1930 in a book called *Mathematical Climatology and the Astronomical Theory of Climatic Changes*. Milankovitch was correct: Ice Ages were linked to Earth’s orbital fluctuations. Though, like most, he thought that severely cold winters brought on long-term cold periods, it was Russian-German meteorologist Wladimir Köppen – the father-in-law of tectonic geologist Alfred Wegener – who realized that the process was much more complicated and terrifying.
Köppen believed that the cause of the ice ages was cool summers, not harsh winters. If an area experienced a very cool summer, then the sun's rays would reflect from the land, and this would worsen the cold, and cause more snow to fall. As a result, the land would become permanently snow-covered. Once the snow turned into ice, that location would become colder, which would result in even more snow. As glaciologist Gwen Schultz said, "the formation of an ice sheet is not determined by how much snow falls, but on how much does not melt – no matter how small." Ice Ages can start with a particularly odd summer, where the unmelted snow reflects heat and exacerbates the cooling effect. As McPhee said, "it is a constantly growing process, and the ice sheet then begins to move when it's formed." This means there are moving glaciers, and then an ice age.
In the 1950s, as a result of imperfect dating techniques, scientists could not correlate the known timeline of Ice Ages to Milankovitch's exact calculations of orbital patterns, and so Milankovitch and his calculations grew unpopular. By the time he died in 1958, Milankovitch had not been able to prove the accuracy of his cycles. It got to the point where, to use a description from the time, "You would be eager to find a geologist or meteorologist who believed that the calculation was more than just an antique." Milankovitch's theory was finally ratified in the 1970s when the potassium-argon dating methods were improved and used to date sediments from ancient seabeds.
The Milankovitch cycles alone are insufficient to explain the patterns of Ice Ages. Many other factors must be considered – especially the distribution of the continents, particularly the presence of polar landmasses – but our understanding of these things remains incomplete. There is a suggestion that, if you were to move North America, Eurasia, and Greenland 500 kilometers north, we would likely be in a constant Ice Age. We seem lucky to have struck a spell of good weather. We are notably short of understanding of the cycles of interglacial periods, which is a time of fairly warm weather within an ice age. It may be unsettling to learn that the entire time of human civilization - the development of agriculture, the setting up of towns, mathematics, literature, science, and pretty much everything else - has occurred in a period of unusually pleasant weather. The most recent periods of interglacial warmth have only lasted for 8000 years. So far, our current period has lasted 10,000 years.
We are technically still in an ice age, although it is now a smaller ice age - though maybe not to the extent that people believe. During the peak of the last ice age, which was around 20,000 years ago, 30% of the land surface of the Earth was covered by ice. Now, about 10% of the land is covered in ice. (Further, another 14% of the area has permafrost.) Around three-quarters of the fresh water on Earth is frozen, which means the poles are ice-covered. This is an extremely unusual occurrence since the Earth was formed. It may seem commonplace to many of us that it snows in many locations in the winter, and that wetter countries like New Zealand have permanent ice. But this is extremely rare over the entire course of Earth's history.
The surface temperature on Earth has been higher for vast periods, where there were no permanent glaciers. The current ice age - and actually, ice ages - initially started around 40 million years ago, and they went from a really harsh phase, to a less-harsh phase. We are living in the less-harsh phase. New ice ages regularly remove the evidence left behind by old ice ages, which means that the further back you travel in time, the less complete the evidence becomes. In the last 2.5 million years or so, it seems like we have experienced at least 17 harsh Ice Ages. This is the period that upright apes and modern humans have occupied. It's often said that the two suspects for initiating the current ice ages are the formation of the Himalayas and the Isthmus of Panama. The Himalayas blocked air movement, while the Isthmus of Panama changed the course of the ocean currents. In the last 45 million years, the island of India has drifted 2000 kilometers and crashed into Asia. The outcome of this was that the Himalayas rose, and the Tibetan Plateau was formed behind them. It is thought that the heightened altitude of the Plateau not only caused colder temperatures, but also changed the direction of the winds, blowing them towards the North American areas, making those areas more prone to protracted cold. Then, approximately 5 million years ago, the land of Panama rose out of the sea, and connected the two American landmasses. This affected the movement of warm water from the Pacific to the Atlantic, which changed the patterns of rainfall over half the world. As a result of this, Africa dried out. This forced hominids to leave the trees and start hunting for new ways of surviving in the newly created savannah.
Whatever happens, it seems like we will be experiencing a very long ice age as the oceans and continents have become more akin to their current formations. John McPhee suggests that we will experience roughly 50 more ice ages, and each will last about 100,000 years, before we can hope to expect a very long period of thaw.
50 million years ago, ice ages did not occur on Earth in a regular fashion. But once they did occur, their duration and scale have been really scary. The earliest large ice age happened 2.2 billion years ago. The next 1 billion years was a warm period. After this period, the next Ice Age was bigger - so much so that scientists refer to that age using terms such as "Snowball Earth" or "Hyper Ice Age".
However, "Snowball" is not good enough for the extent of the really harsh conditions during this period. It is theorized that, as the amount of sunshine falling on the planet was reduced by 6%, it reduced the Earth's capability of producing greenhouse gasses to retain its heat. Earth turned into a snow-covered landmass, and temperatures fell by 45 degrees Celsius. The entire surface of the planet was frozen solid - high-latitude oceans had 800 meters of ice, and even tropical oceans had ice that was tens of meters thick.
The main issue with this theory is that, the geological view is that pretty much the whole planet, even the equator, was covered in snow and ice. But the biological view makes it clear that there must have been pockets of water that were not frozen. First, the cyanobacteria still existed and were carrying out photosynthesis. Photosynthesis calls for sunshine, but you would soon find that as you travel through the ice, the light would get dimmer, and would be impossible to see through in a few meters. There are 2 theories to explain this: small pockets of water did not actually freeze, and perhaps there were areas of warm water; ice structures existed in a translucent form, which sometimes occurs in nature.
If the Earth was frozen, how did it warm up? This is a tricky question to solve. A planet in a frozen condition will remain this way indefinitely, because too much heat is reflected. It seems like Earth's internal magma was the force that saved us. It seems like the crust saved us yet again. We think that volcanoes saved us. The eruptions managed to puncture the ice and the subsequent heat and gasses that were unleashed melted the surface ice. This allowed the atmosphere to be changed. It is rather interesting that this really cold period ended with the Cambrian explosion - the spring of life. But, such a spring does not always have fine weather - as the planet warmed up, it experienced some of the most awful conditions imaginable - gales that were the size of skyscrapers, and unbelievable downpours.
During this time, tube worms, clams, and various other types of life that cling to the sea floor, no doubt continued, as though nothing had happened. And all other life on the planet nearly became extinct. We do not know much about this period.
Compared to Snowball Earth, the more recent ice ages appear much smaller. However, even by modern standards, they are enormous. The Wisconsin ice sheet that covered Europe and North America was approximately 3 kilometers thick in some locations, and would move at about 120 meters per year. Even at its farthest range, the ice sheet was still about 800 meters thick. What a sight that must have been! Just imagine standing at the bottom of such a high wall of ice, and behind it, several million square kilometers of pretty much nothing, besides a few icy peaks. Continents were sinking as a result of the pressure of the ice sheet. Even 12,000 years after its retreat, these areas have not risen back to their initial positions. As the ice moved slowly, it would not only change the place of boulders and moraines, but also would leave behind vast areas - like Long Island, Cape Cod, and Nantucket. It's easy to understand why previous geologists were unable to accept the Earth-shaping power of the ice sheet.
If these sheets were to come back, we don't have any tools to change them. In 1964, Prince William Sound in Alaska experienced the largest recorded earthquake in North America - it was 9.2 on the Richter scale. It caused the land surface to raise by 6 meters. The earthquake was so powerful that ponds in Texas splashed over the edge. But what effects did that unheard of earthquake have on the glaciers in Prince William Sound? Pretty much nothing. The glaciers ignored the earthquake and continued.
For a long period, we believed that the Earth gradually moved into and out of ice ages, and the cycles spanned for hundreds of thousands of years. Now, it is known that this is not the case. The analysis of ice cores from Greenland, provides us with a very detailed record of the Earth's climate change for more than 100,000 years. The outcome is not positive. It seems that, in our recent history, the Earth has not been the comfortable haven that we had believed. The climate has been violently alternating between warmth and intense cold.
Around 12,000 years ago, Earth was near the end of its most recent large ice age. The climate was becoming warmer, and very fast. But suddenly, it went back to 1000 years of harsh conditions. That time is scientifically referred to as the Younger Dryas. (That name comes from a flower that is called Dryas, and it was one of the first plant forms to start regrowing after the ice retreated. In scientific history, there's another period called Older Dryas, but it is not as well-defined.) Near the end of the 1000-year-long cold spell, the average temperatures quickly grew. They rose by 4 degrees Celsius, in 20 years. This may not seem scary, but it is enough to turn the Scandinavian climate into the Mediterranean climate in only 20 years. In localized areas, such changes are greater. Ice cores show that the temperatures in Greenland changed by 8 degrees Celsius in 10 years. The shifting climate patterns changed the levels of rainfall, and growing conditions. This could be easy to handle when there were few people. But now, the outcomes are hard to imagine.
Most disturbingly, we do not know - almost at all - what natural occurrence causes the Earth's temperatures to shift so quickly. As Elizabeth Kolbert noted, "no known outside force - not even a hypothetical outside force - causes the Earth's temperature to change as significantly or frequently as indicated by the ice cores. In all this, it seems that there is," she continues, "an extensive and quite terrifying feedback loop." It is possible that this is related to disruptions to the oceans and their currents, but we have lots of steps to take before all is understood.
One theory suggests that, during the Younger Dryas, the large flow of icy water that ran into the ocean reduced the amount of salt and density in the seawater in the Northern Hemisphere. This caused the Gulf Stream to shift south, as a driver might shift the steering wheel to prevent a crash. Without the warmth that the Gulf Stream would bring, the climate of higher latitudes returned to harsh conditions. But this does not explain the reason that the Gulf Stream did not move as it used to when the Earth warmed up again 1000 years later. But this did trigger an unusually stable period which is referred to as the Holocene era, and it is the era we now live in.
There is no reason that this phase of climatic stability will last forever. In fact, various meteorological experts think that the climate is getting worse. It is a fairly common belief that global warming would stop the planet moving back to glacial conditions. But, as Kolbert notes, when unpredictable climate variations occur, "the worst thing to do is something that can cause mass monitoring." Someone even thinks that the increase in temperature will cause an ice age to occur. This may appear counter-intuitive. However, the thought is that a slight increase in temperature might speed up evaporation, and this might cause thicker clouds, which causes continuous periods of snow in high-latitude locations. Therefore, a rise in global temperature might cause localized areas of North America and Northern Europe to experience greater cold. This makes sense, albeit it is confusing.
The climate is triggered by lots of variables - changing amounts of sulfur dioxide, drifting continents, solar activity, changing Milankovitch cycles - and understanding the past is as hard as forecasting the future. Many things are barely understood. For example, after the continent of Antarctica drifted to the south pole, it was not covered in ice for at least 20 million years, and was instead covered with vegetation. That just seems like a tall tale now.
Even more extraordinary are various known areas where later dinosaurs settled. British geologist Stephen Trulry found that forests around 10 latitudes of the Arctic Circle were home to large animals, including Tyrannosaurus Rex. "This is almost incomprehensible," he wrote, "as the high-latitude areas are in darkness for 3 months of the year." What is worse is that there's now proof that the high-latitude areas also experienced cold winters. Oxygen isotope studies show that the climate around the Alaskan city of Fairbanks was the same in the late Cretaceous, as it is now. What was the Tyrannosaurus Rex doing there? It must have migrated over long distances, or must have lived in darkness with snow and ice for sustained periods. There was nowhere in Australia that they could move to for better weather - because it was located near to the South Pole. How were the dinosaurs able to survive in those conditions? We can just guess.
It is important to note that, if an ice sheet should be formed again for any reason, this time there will be much more water to play with. The Great Lakes, Hudson Bay, and countless lakes in Canada, they were not present, and were therefore unable to feed the last Ice Age. They are all the products of the last Ice Age.
On the other hand, the next stages in our history will be that lots of ice sheets melt, rather than the formation of ice sheets. If all the ice sheets were to melt, sea levels would rise by 60 meters - 20 stories - and all the coastal cities in the world would be underwater. It is more likely that, in the short term at least, the ice sheet in West Antarctica will collapse. In the past 50 years, temperatures in the waters around Antarctica have risen by 2.5 degrees Celsius, and the collapse of the ice shelves has greatly increased. The geology of the area means that large scale collapses are more likely. Should this occur, global sea levels would increase - quickly - by 4.5 - 6 meters.
It is clear that we are uncertain whether the future years will be cold, or hot. It is clear that we are living in uncertain times.
As a point of interest, ice ages are actually a good thing for the Earth. Glaciers grind down rocks, creating fertile new soils. They create fresh water lakes, that feed a large volume of animals. They trigger the movement of plants and animals, and make the Earth live. As Tim Flannery said, "To work out the path that humans have taken over any continent, you just need to ask that continent this question: 'Did you have a solid ice age?'" With that in mind, we will now see how one ape managed to handle the changes.