Ocean: A History of the Atlantic Before Columbus

INTRODUCTION

Birthing pains

Catastrophism

– Plate tectonics

– Making a monkey of Columbus

– Geography is destiny

– The wrong end of the world

When was the Atlantic born? The sixteenth-century Flemish cartographer Abraham Ortelius (1527–1598) thought he knew. Ortelius had mapped the world more accurately than any previous cartographer, and he was struck by how closely the Atlantic coasts of the Old and New Worlds seemed to fit together. Could this possibly be a coincidence, he asked? It seemed to him that ‘the Americas had been torn away from Europe and Africa by earthquakes and sudden floods’. He argued that ‘the vestiges of the rupture reveal themselves, if someone examines a map of the world and considers carefully how the eminences and bays of the coasts of the three continents attach to one another’.²

Ortelius believed that this violent separation, which created the Atlantic Ocean, must have occurred as a result of the catastrophic overnight destruction of the legendary island of Atlantis, which in his day was believed to be a historical event. As births go, labour was agonizingly painful but mercifully brief.

Catastrophism

The matching fit of the opposite coasts of the Atlantic was obvious for all to see, and even more so after the continental shelves had been charted accurately in the nineteenth century, but how was it possible that great masses of solid land could roam freely over the Earth’s surface? For Ortelius, a catastrophe of Biblical proportions was the only imaginable explanation. Catastrophism was very popular in early geological thought. In Ortelius’s day, most Europeans accepted that the mythological Biblical account of the Creation was literally true and that the world was, therefore, only about 6,000 years old. Not only did all of human history have to be crammed into this narrow time frame, but all of geological history too. The Earth was simply not old enough for geological changes to have happened gradually; mountain ranges and oceans, if they had not been present since the Creation, could only have been the result of sudden cataclysmic events of unimaginable power, like Noah’s Flood, which, like the destruction of Atlantis, was also then believed to be a historical event.

Catastrophism went out of fashion in the nineteenth century, as geologists steadily amassed evidence proving that the Earth was in reality many hundreds of millions of years old. That was more than time enough for continents to move, mountains to grow and oceans to open and close. And now, to support this, there was persuasive fossil evidence, such as the fossils of Glossopteris, a tropical tree that flourished in the Permian period (299–252 million years ago), which geologists were finding in South America, southern Africa, India, Madagascar, Australia and even in deep-frozen Antarctica. Evidence such as this led the German geologist Alfred Wegener (1880–1930) to formulate his theory of ‘Continental Drift’. Wegener proposed that, around 300 million years ago, all of the Earth’s continents had been joined in a single supercontinent he named Pangea (‘all the Earth’), surrounded by a superocean, since called Panthalassa (‘all the sea’). It was from the break-up of this supercontinent that the modern continents and oceans had been created as its fragments had ‘drifted’ apart. While other geologists could see merit in Wegener’s theory, it struggled to find acceptance, because there were no known geological forces capable of moving continents around the globe.

Plate tectonics

Had Wegener not died during a geological expedition to the Greenland ice cap in 1930, he might conceivably have lived long enough to see himself vindicated. The breakthrough came in 1953, when the American oceanographer Marie Tharp mapped the ocean floor and discovered the Mid-Atlantic Ridge, a 16,000-kilometre-long chain of underwater mountain ranges and rift valleys running down the middle of the Atlantic Ocean from the Arctic to the Antarctic like the spine of some vast primeval sea serpent. This turned out to be only a part of a continuous 40,000-kilometre-long chain of ridges and rifts on the beds of all the world’s oceans. These ridges, it was discovered, were volcanically active zones, creating and spreading new ocean floor. This discovery paved the way for the modern science of plate tectonics (the geological equivalent of Darwinism), which explains not only how continents can move and new oceans can be created and destroyed, but earthquakes, volcanism and mountain-building too.

The missing motive force that could move continents was convection currents rising from the Earth’s hot core. The Earth’s rocky crust is as solid as it feels, but the layer which underlies it, the mantle, is slightly plastic at geological scales, and it flows with the convection currents, stretching, tearing and fracturing the crust as it does so. The movement is infinitesimally slow, around 2.5 centimetres a year, the same rate that human fingernails grow, but it constantly creates and reabsorbs the ocean floor and rearranges the continents. For most of geological time, the continents have been scattered randomly over the globe, but on at least five, perhaps as many as ten, occasions, the continents have been welded together into vast supercontinents surrounded by superoceans: Wegener’s Pangea was the last of these, but, some 200 million years in the future, another one will form. It’s already got a name: Novopangea.

The same forces that create supercontinents also tear them apart again, scattering the continents over the globe once more. It was from the break-up of Pangea that the Atlantic Ocean was born. That break-up began around 200 million years ago between what became North America and Africa. It was accompanied, and perhaps caused, by a catastrophically violent volcanic outburst of the sort that would not have disappointed Ortelius: it may have led to the mass extinction that marks the boundary between the Triassic and Jurassic periods. South America did not begin its divorce from Africa until about 117 million years ago, and it too was accompanied by a violent volcanic episode. Once South America’s separation was complete, around 83 million years ago, it began to drift slowly west and north, towards North America. When the two continents met and joined, as recently as 2.8 million years ago, the Atlantic we know was fully born: it is the youngest of the Earth’s oceans.

Making a monkey of Columbus

The plants and animals that were now stranded on their island continents took their own evolutionary paths, but, despite the widening oceans between them, there could still be some surprising contacts. It is now well established that the first human inhabitants of the Americas came from Asia via the Bering Strait land bridge during a period of low sea level during the Ice Age, and it was long believed that that the ancestors of today’s South and Central American monkey species must have made the same journey only a few million years before them. Recently discovered fossil evidence from South America has turned that assumption on its head: they are all descended from African ancestors who arrived in South America between 32 and 35 million years ago. This was long after the two continents had fully separated, so these monkeys must have been the first primate oceanic seafarers, beating those other primate seafarers, Leif Eriksson and Christopher Columbus, across the Atlantic by a comfortable margin. It isn’t credible that these monkeys were voluntary emigrants: they were most likely swept out to sea in a storm and survived on a natural raft of floating vegetation. It helped that at this time the Atlantic was only around 1,500 kilometres wide, about half its modern-day narrowest point between Liberia and Brazil, and also that, before South America linked up with North America, the winds and ocean currents were more favourable for east-to-west Atlantic crossings than they are today. What’s even more surprising is that the fossil evidence shows that at least two different species of monkey made the crossing a few million years apart. Monkeys weren’t the only land mammals to make the crossing; they were preceded by the ancestor of that pig-sized South American rodent, the capybara.

Geography is destiny

The human history of the Atlantic began in southern Africa well over 100,000 years ago, but it would be Europeans who would discover the ocean in the fullest meaning of the word. Almost all the coasts of the Atlantic had been discovered by someone by the time the last Ice Age came to an end around 12,000 years ago, but what they knew of the wider ocean was limited to their own coastal waters. Europeans were the first to learn how to sail the open Atlantic and explore and chart all of its coasts, the first to discover the ocean in its entirety and then use those skills to do the same in the rest of the world’s oceans. This was no accident of history; it was largely determined by the geography of the Atlantic itself.

Where are the places in the world that advanced seafaring first began? For a start, none of them are on open ocean coasts. Almost everywhere in the world, humans who lived on sea coasts quickly learned to build rafts or canoes the better to catch fish offshore, but where the view out to sea was just an empty horizon, the technology rarely developed any further without some outside stimulus. Neither on Africa’s long west coast, nor on South America’s Atlantic or Pacific coasts. Our earliest primate ancestors probably already well understood that open water was dangerous, so, unless there was some obvious advantage to sailing far out to sea to compensate for the innate danger of drowning, humans rarely strayed far from the shore. Inevitably, some of those who ventured out to fish would have been blown far out to sea beyond the horizon. If this happened off the South American or West African coast, those who were lucky enough to make it back to the shore would have reported that there was nothing at all out there, only the ever-receding horizon where the sky met the sea.

What was needed for more advanced seafaring traditions to begin developing was attainable goals, such as offshore islands visible from the shore or the chance to save days of walking around a bay or inlet of the sea by paddling a boat directly across to the other side. Some parts of the world are particularly rich in such attainable goals. The Southeast Asian archipelago, with its thousands of intervisible islands, was one such place, a friendly nursery where the ancestors of the Malays, Polynesians, Melanesians and Micronesians learned the skills that enabled them to navigate the Indian and Pacific oceans in distant prehistory. In the Atlantic, the nursery seas with the attainable goals were, mostly, at least, around Europe. With its many peninsulas, bays and fjords, Europe has the longest coastline in relation to its area of any continent, over three times longer than Africa’s, with only one third of the area. Europe also has inland seas, the Baltic Sea, the North Sea, the English Channel, the Irish Sea and, most of all, the Mediterranean Sea, which it shared with North Africa and Asia; these bounded seas offered manageable challenges, where seafarers could watch the land disappear over their sterns, confident in the knowledge that another landfall was never far away. This made them ideal environments for Europeans to learn the shipbuilding and navigation skills that allowed them, eventually, to master the Atlantic.

North America’s coastline runs Europe’s a close second when it comes to length in relation to land area, and, while much of it is ice-bound, the island-studded Caribbean looks full of potential to be a nursery sea. Yet, despite the apparently favourable environment, at the time Europeans arrived in the New World, in the fifteenth century, even in the Caribbean large dugout canoes were still the limit of seafaring technology. Sails and oars were unknown. This absence of more advanced seafaring technology was a consequence of environmental factors specific to the Americas which determined that the transition from hunting and gathering to farming took some thousands of years longer than it did in most of the Old World. In the Old World, farming, and the population growth that resulted, hastened developments such as metalworking, the growth of states and long-distance trade, all of which promoted advances in shipbuilding and navigation: it was, for example, the demand for tin, copper and silver in the Bronze Age Mesopotamian civilizations that first sent Mediterranean seafarers out into the distant Atlantic. In the fifteenth century, the Andean and Mesoamerican civilizations were just attaining the technological level of the Old World’s Bronze Age, and elite demand for prestigious copper, bronze and gold objects was stimulating growth in long-distance trade, just as it had in the Old World. During his fourth voyage to the New World, in 1502, Columbus encountered a large Mayan trading canoe off the coast of Honduras. Among the cargo, he found that the traders carried ‘hatchets resembling the stone hatchets used by the other Indians, but made of good copper; and hawks’ bells of copper, and crucibles to melt it’. Mayan metalsmiths travelled with their products, spreading knowledge of metallurgy along maritime trade routes in much the same way that it had been spread by itinerant smiths in Bronze Age Atlantic Europe. The indigenous American civilizations were developing along the same trajectory as those in the Old World; plank-built boats with masts and sails would no doubt have come with time, but the arrival of Europeans in 1492 stopped the clock.

If geography fostered advanced seafaring in Europe, it also long delayed the moment when Europeans became true oceanic sailors. By the fourteenth century, when the Europeans were on the brink of their oceanic expansion, the Micronesians, Melanesians and Polynesians had already been sailing the open Pacific, a far larger ocean than the Atlantic, for at least 2,500 years. What the Pacific had in abundance and the Atlantic lacked was oceanic archipelagos, especially in the west. Most of the Atlantic archipelagos are on the continental shelves. There are only a handful of isolated volcanic islands and four oceanic archipelagos in the Atlantic: the Azores, Madeira, the Canaries and the Cape Verde Islands, collectively known as Macaronesia, a name derived from Greek, makárōn nēsoi, the ‘islands of the fortunate’, an allusion to the belief that the souls of the blessed went to dwell on paradisiacal islands in the west. Unlike the Pacific, with its hundreds of archipelagos, there was a severe shortage of attainable goals for apprentice ocean navigators and little chance of accidental discoveries by off-course mariners. Most of the lands such seafarers thought they sighted were mirages and phantoms. Only in its far northern limits is there an abundance of islands leading out into the ocean, and it is very telling that it was here, and only here, that any Europeans, in this case the Norse, crossed the Atlantic before Columbus in 1492, using the Shetland Islands, the Faeroes, Iceland and Greenland as convenient stepping stones to the Americas. Another geographical factor which drew European seafarers out onto these chilly northern Atlantic waters was their fish stocks. Fertilized by silt from Arctic glaciers and great continental rivers like the St Lawrence and the Rhine, these are among the world’s richest fishing grounds.

Winds and currents also discouraged Europeans from straying too far from home waters. The prevailing westerlies which batter Europe’s Atlantic coast stood in the way of mid-latitude ocean crossings, while the prevailing northeasterly winds and ocean currents along North Africa’s Atlantic coast discouraged exploration in that direction because they made it so difficult to sail back again. It was only in the fourteenth or early fifteenth century, when the Portuguese discovered the phenomenon they called the volta do mar (the ‘turn of the sea’; see Chapter 14, page 389), that European seafarers learned how to use these seemingly adverse winds to their advantage and break out into the wider world’s oceans.

However, it was not only geography that held Europeans back; there were cultural factors too. No, it was not the fear of sailing over the edge of the world: belief in the sphericity of the Earth was well established by the beginning of the Christian era. It was that medieval Europeans had a cultural inferiority complex that left them in awe of the achievements of the ancient world. This gave them an exaggerated respect for the learning of the ancient Greeks and Romans and a world view that told them that there was nowhere else to go beyond the bounds of the three continents of Europe, Asia and Africa that they had always known. Medieval Europeans understood that in principle it would be possible to sail west to Asia, but it was half a world away and no ship yet built could traverse so much empty ocean. Nor could Asia be reached by sailing around Africa, because they dared not pass Cape Bojador, the ancient point of no return on the coast of Western Sahara, beyond which the sea was believed to boil in the equatorial heat. Respect for the ancients kept Europeans bottled up in the northeast Atlantic for centuries, but all the while their ships steadily improved and their navigation became increasingly scientific. It took intellectual courage, as well as physical courage, to challenge their inherited wisdom, but when Europeans finally attained both, in the fifteenth century, they were more than ready for the challenges of the world’s oceans.

The wrong end of the world

However, none of this was enough by itself to draw Europeans out onto the world’s oceans; they also needed an economic incentive, and that too was related to geography. In terms of pre-Columbian geography, Europe was at the wrong end of the world. By the late Middle Ages, growing prosperity in Christian Europe was leading to rising demand for luxuries, like silk, spices, jewels, ivory and gold, which came either from east Asia or sub-Saharan Africa and could only be bought from Muslim middlemen in the Middle East or North Africa. Centuries of mutual hostility meant that Europeans objected to this, not only because they had to pay monopoly prices but because it felt like they were funding their enemy’s armies and navies. Europeans, therefore, had a strong incentive to try to find trade routes that cut out the Muslim middlemen. This economic geography, too, explains why there was no attempt to enter the Atlantic from the east: the Muslim Middle East did not need new trade routes that might threaten its monopoly on east–west trade and, as for India and China, they did not need to discover the world; the world came to them.

1

Who ate the first oyster?

C.168,000 BP–5000 BC

The Atlantic refuge

– The Neanderthal Atlantic

– Out of Africa

– Climate change brings new ways

– The first boats

– Doggerland

– The limpet eaters

– Picturing the Mesolithic

– Archaic adaptations

– The oyster empire

– The ‘Uttermost Part of the Earth’

– In a state of nature

– Killing with kindness

‘He was a bold man who first ate an oyster,’ wrote Jonathon Swift,³

and anyone who can remember the first time they were offered a live oyster will readily agree with him – they look anything but appetizing. Shellfish are, for most people, either an acquired taste or one they never acquire. Thanks to archaeology, we may now know, roughly, when and where the adventurous beachcomber, man or, just as likely, woman, lived who first ate a shellfish: it was on the Western Cape coast in South Africa around 160,000 years ago. This was an event of more than culinary interest; it marked the evolution of behaviourally modern humans – that is, people like us. Whoever it was who ate it, that first meal of shellfish began the human history of the Atlantic Ocean.

Scatters of roughly worked stone cleavers and hand axes on sites as far apart as South Africa, Angola and Morocco tell us that archaic humans, most likely Homo erectus or its evolutionary successor Homo heidelbergensis, were already living on Africa’s Atlantic coast over half a million years ago. Humans and the Atlantic go back a long way. Similar tools from sites only slightly more recent in Spain and France show that the same archaic humans had found their way to Europe’s Atlantic coast not long after that. What these pioneers thought, if indeed they thought anything at all, when they looked out to sea is un-guessable: the inner lives of archaic humans remain elusive. We do not even know if they possessed language; if they didn’t, then they could not have told any stories or dreamed up any myths to explain what they were looking at. Whatever they thought, it seems that archaic humans did not see the sea as a source of food, because there is no evidence even from coastal occupation sites for the exploitation of marine resources. This is surprising, because there is good evidence that archaic humans did sometimes eat freshwater fish, at least. It is possible that evidence has been lost to changing sea levels, but it appears that archaic humans had not yet evolved the adventurous omnivorousness that is such a marked characteristic of modern humans: they were still too much creatures of instinct to be the first to eat shellfish. Though there is strong circumstantial evidence that archaic humans in the Southeast Asia archipelago had some seafaring capacity (even if it only involved a bamboo raft or swimming in the warm tropical waters while holding on to a floating log and hoping not to be eaten by a shark), there is no reason to believe that they ever went to sea in the Atlantic. Archaic humans lived on both sides of the Strait of Gibraltar, only 13 kilometres apart, but genetic studies prove that they never met and mingled. Both populations followed separate evolutionary pathways: those on the African side evolved into anatomically modern humans (Homo sapiens sapiens, i.e. us), those on the European side into the Neanderthals (Homo sapiens neanderthalensis).

The Atlantic refuge

Humans evolved during the Pleistocene Epoch, which lasted from around 2.5 million years ago to as recently as 11,700 years ago: it roughly coincides with the earliest period of human prehistory, known as the Palaeolithic or ‘Old Stone Age’. Often called the ‘Ice Age’, the Pleistocene saw extreme climatic swings from very cold glacial periods, which saw enormous ice sheets accumulate in high latitudes, to milder interglacial periods with temperatures as high as or even higher than those of the present day: some climate scientists would argue that we are living in an interglacial period right now, one that is being artificially prolonged by human-induced global warming, and that, in the geological long term, a return to glacial conditions is inevitable. The environmental impact extended even into the tropics. During glacial periods, so much of the Earth’s water was locked up in ice sheets that the climate became drier and sea levels fell temporarily by up to 100 metres below those of the present day. Forests retreated and deserts and grasslands – tundra, steppe and savannah – spread. In these periods, Africa became so arid that its rainforests almost vanished and deserts and semi-deserts covered around 70 per cent of its land. During the mild interglacial periods, sea levels rose, rainfall increased and the grasslands gave way to forests again.

These were testing times for both plants and wildlife and, it follows, for the early humans, who depended on them for their sustenance. It wasn’t so much the cold that was the problem – not everywhere got cold – it was the instability. Some climate switches were so rapid that they took place within the span of a single human lifetime. Many species were pushed into extinction because they couldn’t adapt quickly enough to the changing conditions. It’s quite likely that we owe our own large brains to this environmental instability, because it created a strong selective pressure in favour of adaptability and intelligence. Despite this advantage, the evidence preserved in our DNA shows that the early human population went through several ‘bottlenecks’, when it may have been reduced to just a few thousand individuals. Humans were saved from extinction by retreating to a handful of areas, known as refugia, in the northeast and far south of Africa, where the environment remained relatively stable. Perhaps the most important of these for human evolution was the rocky coast of the Western Cape region, spanning the boundary between the Atlantic and Indian oceans.

Anatomically modern humans, Homo sapiens sapiens, evolved in Africa nearly 300,000 years ago, but though they may have looked just like us, they did not yet behave like us. There was no sudden leap to behavioural modernity; early modern humans continued to use the same tools and follow the same way of life as their archaic ancestors for another 200,000 years: the development of behavioural modernity was a process, not a sudden event like switching on a lightbulb. Minds, of course, don’t fossilize, but the capacity for abstract and symbolic thought that enables modern human behaviour, including language and art, can be deduced from material culture, and it’s from coastal caves in the Western Cape, at Diepkloof, Ysterfontaine, Mossel Bay, Blombos and the Klasies River Mouth, that the earliest archaeological evidence for behavioural modernity comes. Ground ochre that was probably used for body painting, dating to around 160,000 years, found at Pinnacle Point at Mossel Bay, is currently the oldest evidence hinting at the emergence of behavioural modernity. The occupants of this cave roasted stone in a fire pit to make it easier to flake into sharp tools and spearheads. This was a process that required several careful steps, and therefore, archaeologists argue, it should probably be seen as evidence that they were using language to pass on instructions for complex tasks: if so, they may have told the first stories about the ocean, too. They also produced tiny microblades, sharp stones too small to be useful tools by themselves, which must have been combined to make composite tools such as harpoons or barbed spears. Making complicated tools like these had been well beyond the mental capacities of earlier human species. What is currently claimed to be the oldest known drawing by human hands is a simple geometric pattern, drawn with red ochre, found on the walls of Blombos Cave, which has been dated to around 73,000 years ago. The oldest known portable art comes from Diepkloof Rock Shelter, about 150 kilometres north of Cape Town, where several hundred pieces of broken ostrich shells, engraved with geometrical patterns, were found. The shells, which the inhabitants used for carrying water, dated to around 60,000 years ago. It’s far from clear what was being communicated by these repetitive patterns: one theory is that they represented an idea of group identity.

Early modern humans took refuge in these caves on the Western Cape during one of the coldest periods of the last Ice Age, when Africa was at its most desiccated. Luckily for Homo sapiens, the Western Cape was an exception, enjoying a fairly stable Mediterranean climate, with dry summers and rainy winters, that was not so different from that of the present day. Then, as now, the vegetation was dominated by the biodiverse fynbos (‘fine bush’) of shrubland, heath and patchy woodland. This environment offered a wide range of game, such as gazelles and antelope, tortoises and ostriches, and an exceptionally wide range of plants with edible bulbs and tubers that could be gathered easily with the aid of a simple digging stick. There was also the even more stable environment of the ocean. The seas off the Western Cape are particularly rich because of a convergence between the warm Indian Ocean Aghulas Current and the upwelling cold Atlantic Benguela Current, which brings nutrients from the ocean depths up to the surface, encouraging the growth of phytoplankton. These tiny organisms are the base of the marine food chain, so the area supports abundant stocks of shellfish, fish, seabirds and marine mammals. The sea, therefore, offered reliable and inexhaustible food resources, but only for those whose behaviour was flexible enough to exploit them. Shell middens at Ysterfontaine, a small harbour town around 90 kilometres north of Cape Town, and other sites, indicate that this profound dietary, and cultural, change took place between 120,000 and 164,000 years ago. Mussels and limpets, which were abundant on the rocky coastline, were the first shellfish to be exploited, but they were later joined by periwinkles and whelks. Despite the chance of being washed off the rocks and into the sea by breaking surf, the sheer abundance of molluscs made the risk worthwhile. This abundant food was also easy to prepare: charring on the shells is evidence that they were simply thrown into the embers of a fire to cook until they opened. Bones found in the middens are evidence that the Ysterfontaine people hunted Cape fur seals, cormorants and penguins along the shoreline, but, so far, no site on the Western Cape has produced convincing evidence for fishing. Whale barnacles that have been found in the middens probably should be seen as evidence for scavenging meat and blubber from beached whale carcasses. As for oysters, they don’t seem to have been eaten at Ysterfontaine, and their shells are only rarely found in middens at other contemporary sites in the Western Cape: they were plainly not anyone’s first choice of shellfish. So far, the earliest evidence for the routine consumption of oysters comes from that other African refugium, in the northeast, on Eritrea’s Red Sea coast, where they were being collected along with clams and crabs as early as 125,000 years ago.

Dietary modernity didn’t emerge all in one go; the quantities of marine food remains found are quite small, so it appears that the early modern humans of the Western Cape preferred terrestrial foods, perhaps only turning to the sea when they failed. There is an important caveat to this conclusion, however. For most of the period that these caves were occupied, sea levels were lower than they are today, so some of them would have been many kilometres inland. If their inhabitants preferred to eat their seafood fresh, close to the places where they found it, the evidence of their meals is now underwater.

The Neanderthal Atlantic

Anatomically modern humans first migrated out of Africa around 100,000 years ago, but they got no further than the Middle East and, after a few thousand years at most, they died out for reasons we don’t understand. The definitive migration out of Africa took place about 30,000 years later, and by about 12,000 years ago modern humans had colonized every continent except Antarctica. In the Middle East, modern humans encountered the Neanderthals. Neanderthals had significant physical differences from modern humans; they were stouter, barrel-chested almost, and had shorter limbs; their brains were slightly larger than those of modern humans, but their craniums were longer and lower and they had low brows and prominent brow ridges, which helped give them their popular reputation for being dimmer than the literally high-browed modern humans. They also had prominent bulbous noses and we know from analysing remnants of their aDNA (ancient DNA) that they probably had reddish hair and light skins, unlike modern humans, who at this time were all dark-skinned. Many of their features can be explained as evolutionary adaptations to a cold climate. The short, stout physique is shared by many Arctic peoples today: it is much better at conserving body heat than a tall, slender body. The bulbous nose probably helped heat cold air before it got to the lungs and the fair skin helped them metabolize vitamin D from the limited sunlight of high latitudes. Those modern humans who remained in high latitudes evolved similar adaptations in time. When they were first discovered in the nineteenth century, the Neanderthals were believed to have been knuckle-dragging dimwits, the archetypal cartoon cavemen, armed with clubs and possessed of a limited monosyllabic vocabulary. In recent decades, new discoveries have been eroding steadily the supposed behavioural and cognitive differences between Neanderthals and modern humans. Though Neanderthals used a narrower range of tools than modern humans, they made art and wore body ornaments, manufactured complex tools, cooked their food, probably had some form of religious belief, buried their dead and almost certainly had language like their modern African cousins. Another sign of their modernity: Neanderthals also ate seafood.

The range of the Neanderthals fluctuated along with the climate, but at its greatest it extended from Europe’s Atlantic coast east far into Central Asia and as far south as Israel. Across most of this range, Neanderthals ate a meat-rich diet. Because their only hunting weapon was the spear, Neanderthals needed to get close to their prey to make a kill. Probably for this reason, they only occasionally hunted large and dangerous animals like aurochs, woolly rhinoceros and mammoth, preferring smaller game such as red deer, in wooded areas, and reindeer, on open steppe and tundra. Analysis of tartar on fossilized teeth shows that Neanderthals supplemented their meaty diet with fungi, fruits and berries. However, in coastal areas, Neanderthals were notably more flexible about what they ate than earlier human species.

Probably, nowhere in Ice Age Europe had a more stable environment than Gibraltar, the rocky mountain-peninsula that marks the boundary between the Atlantic Ocean and the Mediterranean Sea. Here, through all the swings globally, the climate remained reliably temperate throughout. About 140,000 years ago, a group of Neanderthals moved into the Gorham’s Cave complex at the base of the cliffs on the ‘Rock’s’ east coast. The cave’s entrance is only just above sea level today and is most easily accessed by boat, but in glacial periods it would have been about 2 kilometres from the sea, on the edge of a sandy coastal plain, and, so, much more sheltered and accessible. Butchered animal bones excavated from the cave show that the Neanderthals were active hunters of ibex, which would have flourished on the Rock, and their favourite red deer. However, instead of depending solely on terrestrial mammals, the Gorham’s Cave people exploited a very wide range of other food sources. Large numbers of rabbits and birds were eaten, both of which they probably trapped, as well as tortoises. Part of the attraction of Gibraltar must have been that it is a major staging post in spring and autumn for birds migrating between Africa and Europe, while its cliffs made it an attractive nesting place for seabirds in the summer. Altogether, the Gibraltar Neanderthals ate 145 different bird species (about a quarter of the total number of bird species known to inhabit Europe). Pine nuts are the only plant food they can be shown to have eaten, but the Neanderthals took advantage of their coastal location to hunt basking monk seals and collect mussels, limpets and sea urchins in large quantities, which they took back to the cave to bake in the fire. Dolphins and tuna were also eaten in limited quantities, but it is not clear how these were caught, because there is no evidence for the specialist fishing gear, such as harpoons and fish spears, that some of their modern human contemporaries used; the dolphins were likely beached. The Gorham’s Cave Neanderthals were so comfortable in their coastal niche that their descendants stayed on for 100,000 years, their way of life barely changing in all that time, so much so that one of their hearths was used continually for 8,000 years.

Coastal sites like Figueira Brava in Portugal, and others in Spain, Italy and Greece, have also provided evidence of the exploitation of marine food sources, so it seems likely that this foraging behaviour was as common among Neanderthals as it was among contemporary anatomically modern humans such as those who lived in the Western Cape. It’s still an open question if Neanderthals built any kind of watercraft. They certainly never reached any of the major Mediterranean islands, despite the low sea levels in glacial periods, but tools identified as belonging to the Neanderthals’ Mousterian culture have been found on a few of the smaller Greek islands, including Kephalonia, so they must have been able to make very short sea crossings by some means. Having said that, there is no evidence that modern humans were capable of doing anything more ambitious than that either until about 48,000 years ago, when the first humans arrived in Australia, a feat that required a sea crossing of at least 90 kilometres even when Ice Age sea levels were at their lowest.

The willingness of Neanderthals to exploit marine food sources challenges the idea that they were somehow less adaptable to different environments than anatomically modern humans. This, and other evidence of behavioural modernity, is making it increasingly difficult to explain why the Neanderthals eventually became extinct. There’s now little reason to believe that they were not as clever as modern humans, and so, although competition with them for resources may be part of the explanation, it is very unlikely to be the whole story. The Neanderthals died out around 40,000 years ago. Those who lived in Gorham’s Cave were among the last survivors, but modern humans cannot have been directly responsible for their extinction, because it was another 10,000 years before they arrived in southern Spain. Studies of surviving Neanderthal DNA show that they had low genetic diversity, best explained by a small population, perhaps as few as 5,000 across their whole immense range. Small, isolated groups like the Gorham’s Cave Neanderthals may have suffered from inbreeding, with the accumulation of genetic imperfections leading to a collapse of fertility. A small population would also explain the slower pace of technological innovation among Neanderthals. Larger groups are more likely to have new ideas and more likely to find people willing to accept and build on them. This is why, in recorded human history, it is the crowded cities that have always been the main centres of cultural and technological innovation.

Neanderthals and anatomically modern humans may be scientifically classified as different species, but it is clear that when they encountered each other they saw other people. A bit ugly maybe, but people just the same, not animals or aliens. Conflict over territory was common among modern hunter-gatherers, so we shouldn’t imagine that that their first instinct was to embrace one another as long-lost cousins, but embrace one another they certainly did sometimes. Neanderthals and modern humans interbred, and all non-African modern humans have inherited 2–4 per cent of their DNA from the Neanderthals. Rather than becoming literally extinct, the Neanderthals may simply have been genetically swamped by the far more numerous modern humans who kept pouring out of Africa.

Out of Africa

The Atlantic was the greatest obstacle to the human diaspora out of Africa. When, 70,000 years ago, anatomically modern humans left Africa for the Middle East, they split into two great branches. One branch headed west into Europe and by about 45,000 years ago had reached the Atlantic, and there it stopped, blocked by the ocean to the west and the vast ice sheet that covered almost all of the northern half of the continent. They had reached the edge of the world and would go no further in that direction for all of 44,000 years. The second branch of humanity headed east and, thousands of years later, some of its distant descendants crossed the Bering Strait from Asia into the Americas and had populated both coasts of the continents, south all the way to Tierra del Fuego, by about 11,000 years ago. It was only when Norse explorers met Native Americans in Vinland around a thousand years ago that these two branches met, and humanity finally completed its global circumnavigation.

On the face of it, at least, the first modern humans in Atlantic Europe specialized in hunting the vast herds of reindeer, horses and bison that roamed Ice Age Europe’s tundras and steppes, changing camp often as they followed their seasonal migrations. Those migrations were predictable and reliable: the wildlife would follow the same routes, converge on the same river crossings, the same summer and winter pastures year after year, and their meat came in conveniently large packages. Even those hunters whose wandering took them close to the sea seem only occasionally to have turned to it for sustenance, relying on marine resources no more than their ancestors in the Western Cape had, or the Neanderthals they replaced. For example, at La Riera Cave in Asturias on Spain’s Atlantic coast, which was occupied from around 23,000 years ago to around 13,000 years ago, some 26,600 shells were deposited but, spread over 10,000 years, that doesn’t add up to a great reliance on shellfish. Shellfish may be rich in protein, vitamins and essential minerals, but they are low in calories and so probably would not have been first-choice foods for people living in the chilly sub-Arctic climate of Ice Age Europe. The same cannot be said of marine mammals, such as seals and walrus, with their thick layers of energy-rich blubber, valuable not only as food but also for heating and lighting. Nonetheless, evidence that marine mammals were actively hunted is slight, although it is likely that most of the coastal sites, where marine resources could have been exploited more intensively, have been submerged by the post-glacial rise in sea levels.

One group of marine mammals that certainly was exploited was whales. There is no evidence that late Palaeolithic Europeans possessed any seafaring technology, so they were most likely opportunistically scavenging the carcasses of beached whales rather than actively hunting them. A beached whale would have provided a hunter-gatherer band with a windfall of meat and blubber, but it would not have been without risk if bears got to it first: bears have a strong sense of ownership of their food, and they really don’t like to share. All the same, it’s hard to imagine that late Palaeolithic hunter-gatherers would have passed up such a feast had the opportunity arisen, though that is pure surmise. The only parts of whales that we actually know for certain they used are their bones, which they could have collected quite safely from the bleached skeletons of long-dead animals, and that was not for food but for toolmaking. Although dozens of whalebone projectile points have been found, it was most commonly used to make woodworking wedges and chisels. Whalebone is not as dense as antler or the bones of terrestrial mammals, such as deer, making it easier to work, while it is also more impact resistant, making it well suited for hard use. Most of the tools so far discovered show signs of considerable use and repair, so they were obviously a valued part of the Palaeolithic toolkit and were kept for a long time. Their users probably valued whalebone tools because they were very durable and did not need to be replaced very often. The bones may also have been valued for their large size, which allowed larger tools to be made. Some whalebone tools were decorated with incised geometrical patterns and animals, while others have grooves to fit tiny microlithic flint blades which would have been held in place with resin glue.

During the Magdalenian period (c.18,000–12,000 bp) whales’ bones were in great demand for toolmaking and were widely distributed. Whalebone artefacts have mostly been found in Cantabria and the Pyrenean region, straddling the modern border between Spain and France, where hundreds have been found spread across nearly forty cave sites. As very few of these sites are close to the sea, the occupants must have been acquiring them by trade. The pattern of distribution suggests that the bones were distributed via a 600-kilometre exchange network, the earliest known network for trading marine products, extending from the Cantabrian coast into the Pyrenees and beyond as far as the Ariège valley in southern France. It would probably be wrong to imagine that there were itinerant Palaeolithic whalebone merchants: the bones are most likely to have been distributed from one band to another as part of exchanges of useful commodities intended to cement mutually supportive social networks that could be called upon in hard times. Whalebone tools have been found as far from the Atlantic as Andernach in the German Rhineland, hinting that this network may have been even more extensive. Only finished whalebone tools have been found in caves, no whole bones or toolmaking waste, so the tools must have been made elsewhere, probably on the coast where the stranded whales were found, at sites that will now be deep underwater. Isturitz cave, close to the Atlantic at the western end of the Pyrenees, is where the largest concentration of Magdalenian whalebone artefacts has been found, so this may have been an exchange hub for the onward distribution of the artefacts to areas further inland.

The apparent unimportance of marine food resources to late Palaeolithic Europeans is mirrored in the spectacular cave art for which southwest France and northern Spain is justly famous. Far and away the majority of animals portrayed in the art of the period are terrestrial, deer, horses, aurochs and bison being the most common, while sea creatures make only a token appearance. Perhaps the best-known example is found in Tito Bustillo Cave, at Ribadesella on the Cantabrian coast, where there is a two-metre-long 29,000-year-old drawing of a baleen whale. Even in the Ice Age Bustillo Cave was close to the sea, so the whale is almost certainly drawn from life, perhaps to commemorate a stranding and the feast that followed. Other caves and rock shelters in the region have drawings of seals, a salmon, a halibut (a large flatfish), a couple of flounders and two great auks, an extinct flightless seabird. Sea creatures also appear on a few portable items, such as a beluga whale incised on a pendant made from a sperm whale’s tooth found at Las Caldas in Asturias and a bone pendant with an incised sperm whale from Arancou, not far from the Atlantic coast in Basse-Navarre. Add an incised sperm whale on a bone implement from Grotte de la Vache in Ariège and a seal on a slate plaque from Gönnersdorf in the Rhineland and that really is about it. There isn’t a close correlation between the animals late Palaeolithic people chose to paint or draw and those they chose to hunt and eat, but it is still clear that sea creatures didn’t loom very large in their imaginations, just as they don’t seem to have loomed large in their diets.

Climate change brings new ways

As the last glaciation drew to its close around 10,000 years ago, hunter-gatherers everywhere were forced to adapt to rapidly changing environments as the climate warmed, and this brought much greater reliance on the sea for food for those who lived in coastal areas. Over the next 3,000 years, sea levels rose by an average 2 metres every century, twice the worst-case scenario for the twenty-first century as a consequence of human-induced climate change. As water flowed back to the oceans from the thawing ice sheets, sea levels rose, flooding familiar landscapes and campsites (along with all the evidence of Palaeolithic use of maritime resources). Open steppes, with their easily tracked herds of reindeer, horses and mammoths, gave way to dense woodlands inhabited by more elusive game. Food was abundant, it just came in smaller packages. Hunter-gatherers could no longer specialize. Instead they needed to become generalists, exploiting a much wider range of resources, including the sea. In Atlantic Europe, this period of adaptation is known as the Mesolithic or Middle Stone Age, and it is often seen as a transitional period between the Palaeolithic big game hunting way of life and the advent of settled farming around 4000 BC. In North America, the same period is known as the Archaic.

Mesolithic Europe was inhabited by two genetically distinct populations. Whole-genome analysis of their remains shows that the people of the Atlantic west still had the brown or black skin and the dark-brown or black hair of their African ancestors but that they also had strikingly blue eyes. They would have looked clearly different to the hunter-gatherers in eastern and far northern Europe, who, by this time, had evolved the light skins characteristic of modern Europeans.

Mesolithic hunter-gatherers favoured locations that offered a variety of habitats in a small area, especially wetlands, estuaries and coasts. The food resources of these highly productive environments were effectively limitless given the technology available at the time, and this allowed them to adopt more sedentary lifeways than their Palaeolithic ancestors, perhaps moving only between winter and summer camps. New technologies emerged, fishing nets, wickerwork fish traps, barbed harpoons and fishhooks for fishing, bows and arrows for hunting fast-moving small game and wildfowl, woven baskets for collecting shellfish, nuts, berries and fungi, and watercraft to increase access to aquatic resources. In contrast to Palaeolithic humans, Mesolithic Europeans made great use of marine resources when they had access to them. Just compare the size of the Mesolithic shell midden excavated at Ertebølle in Jutland, Denmark, which contained over 50 million shells, along with the bones of fish, seabirds, seals and deer, accumulated over just seven or eight hundred years with La Riera’s meagre 26,600 accumulated over 10,000 years. The importance of seafoods in the Mesolithic diet is further demonstrated by the isotope analysis of a contemporary human burial from Tybrind Vig on the Danish island of Fyn, which showed that the young woman lived mainly on a diet of shellfish, fish and seal meat.

The first boats

In the new world of the Mesolithic, boats were essential to make the most of aquatic food sources, whether on salt or fresh water. On sheltered waters, Mesolithic Europeans used logboats (also called dugout canoes) which were fashioned simply by hollowing out a single tree trunk with adzes and fire. The oldest logboat found so far, dated to between 8040 BC and 7510 BC, found during road-building at Pesse in the Netherlands, looked so crude that it was thought to be an old feeding trough for livestock until radiometric dating proved that it was made millennia before anyone kept livestock in Europe. Experiments with a replica have shown that the Pesse logboat was a perfectly practical vessel for fishing and wildfowling on sheltered waters, but, with a freeboard of only a few centimetres, it would have foundered quickly if taken on the open sea. Some Mesolithic logboats have been found to contain heavy rocks, which were probably carried as ballast to make them more stable – they are quite easy to capsize, as I discovered when paddling a replica in Denmark – while others had clay hearths for small fires, probably as aids to torchlight fishing at night. Logboats might be an unspectacular beginning to the history of Atlantic seafaring, but they had great potential for refinement and expansion, for example, by adding planks to the sides to increase the freeboard, and, over thousands of years, as better woodworking tools and carpentry techniques developed, from these simple beginnings evolved the plank-built vessels of historical times. However, they weren’t the boats Mesolithic people went to sea in, and go to sea they certainly did, the archaeology is quite clear about that.

Roughly as old as the Pesse logboat is a representation of an altogether more seaworthy kind of boat carved or engraved onto an ice-polished rock 72 metres above sea level near Valle, on Efjorden in Nordland in Arctic Norway. The land in northern Norway has been steadily rising since the end of the Ice Age as it rebounds from the vast weight of the Scandinavian sheet which had pressed it down into the mantle. If the ship was originally carved close to sea level, as later rock art was, the ship was probably carved around 10,000 years ago, which would make it the oldest representation of a boat anywhere in the world. The engraving is the barest outline of a boat – at 4.3 metres long, it may actually be life-size – but its profile is identical to hundreds of later and more detailed ship carvings from northern Norway. The boats depicted by these carvings have a distinctive profile, with steep prows and horizontal projections at both ends, which makes them look very similar to traditional Inuit umiaks, light, flexible and buoyant open boats, propelled by paddles, which were made by shaping greased hides around a wooden skeleton or wickerwork frame. Until the advent of outboard motors and fibreglass boats, the Inuit used their very seaworthy umiaks for hunting whales and for transporting family groups on seasonal migrations. As there is little timber in Arctic Norway suitable for building plank boats, it’s likely that the boats in the carvings, some of which have animal-head figureheads, were built and used in a similar way. Hide boats must also have been used further south along Europe’s Atlantic coast. Mesolithic hunter-gatherers settled in the Shetland Islands, which required a voyage of at least 80 kilometres across the North Atlantic from the nearest land, in the Orkney Islands: they certainly didn’t do that in a logboat. Hide boats were made of highly perishable materials, so it’s not likely that any prehistoric remains will be found, but their use around the coasts of Ireland, Britain and France is well documented from around the first century BC.

The post-glacial environmental changes in northwest Europe were particularly complex. As the last glaciation came to an end, water released by melting ice sheets poured back into the seas, bringing rapidly rising sea levels globally. However, in the areas that had been most heavily glaciated, northwest Europe and northern North America, the rising sea levels were cancelled out because the land was also rising due to a phenomenon known as isostatic uplift. The weight of the huge ice sheet centred on Scandinavia had pressed the Earth’s crust down into the slightly plastic mantle by hundreds of metres. Then, much more slowly, the crust, freed of the vast weight of the ice sheets, began to rise as the mantle oozed back into place underneath it. Around the Gulf of Bothnia in the northern Baltic Sea, this rebound is still going on at a rate of nearly one centimetre a year, faster than the predicted rate of sea level rise from global warming. The gently sloping shores here make the consequences of uplift very obvious even within a human lifetime. If a young fisherman built a boatshed by the shore, it would be high and dry by the time he retired. Back in the Mesolithic, when these changes were going on at a faster rate and over a larger area than they are today, some hunter-gatherer bands would have returned to familiar hunting grounds and found them flooded by the sea, while others would have found that a convenient seashore fishing campsite was now lost in a forest. This must have induced a profound sense of insecurity in many people – could anything be relied upon?

Doggerland

The changes to sea level were at their most extreme around what is now the North Sea. At the end of the Ice Age, there was no North Sea. Britain and Ireland were both simply part of the European mainland, while the area now covered by the North Sea was a vast plain broken only by a range of low hills, which today form the Dogger Bank, a shallow area of the sea which is now an important fishing ground. During the later stages of the Ice Age, herds of reindeer, mammoths and woolly rhinoceros roamed this plain, christened Doggerland by archaeologists, and their remains are still there, littering the seabed. Fishermen regularly dredge up the teeth and tusks of mammoths, as well as the tools of the human hunters who followed them across the frigid landscape. As the ice sheets retreated and water began to flow back into the oceans, Doggerland was slowly submerged, but the process created the kind of richly varied landscape that was very attractive to Mesolithic hunter-fisher-gatherers: an ever-changing mix of terrestrial woodland, salt marsh, mudflats, tidal lagoons and estuaries, that offered a year-round buffet of wild foods such as deer and wild boar, nuts and berries, fungi, shellfish, fish, wildfowl and seals. Archaeologists believe that Doggerland could have been one of Mesolithic Europe’s most densely populated regions.

This bountiful landscape was doomed by the warming climate. By around 7000 BC the rising seas had cut Britain and Ireland off from the continental mainland and turned the Dogger Bank into an isolated and fast-shrinking island. Doggerland’s demise was hastened by one of the greatest natural disasters ever to strike the North Atlantic, the Storegga Slide. During the last glaciation, the Scandinavian ice sheets piled up enormous but unstable quantities of rock, sand and clays on the edge of the Norwegian continental shelf. Then, around 6225–6167 BC, the colossal weight of this rubble caused the continental shelf along a length of 290 kilometres to collapse, taking 3,500 cubic kilometres of rock with it into the depths of the North Atlantic and triggering a massive tsunami. The size and spread of the wave has been charted from the deposits it left behind onshore. In the Shetland Islands, the tsunami deposits have been found lying 20 metres above sea level, and it was still 4 metres high when it reached the Firth of Forth over 400 kilometres further south on Scotland’s North Sea coast: flood deposits have been found almost