In fact, it should not be too surprising, given the sheer environmental diversity that spans the Pacific Ocean, but Lapita-carrying (and later Polynesian) settlers were clearly flexible as they felt out their new, yet also familiar, surroundings. They managed local and introduced tree crops, foraged for plant resources and hunted local animals, and introduced new domesticates into tended gardens. The fact that these populations inhabited this vast oceanic space, from the Bismarck Archipelago to western Polynesia, in just a few hundred years shows that they were able to ingeniously and rapidly adapt to a variety of island settings. Moreover, the paucity of remains of introduced domesticates like pigs, as well as chickens and dogs, in early Lapita sites may show the difficulties (or choices made) when establishing stable domesticated communities across this diverse space. In Near Oceania, in and around New Guinea, for example, Lapita settlements are located on the coast or on small islands, tuning in on marine resource use, perhaps as a way of avoiding the existing occupants of this region, who had been using inland resources since the Pleistocene (c. 45,000 years ago). Further east, on remoter islands, Lapita sites are located some distance inland, and it is increasingly evident that they managed and used forest environments at the same time as investing in opened spaces for cultivation and pig penning. The type of island could also make a difference. Volcanic islands, like those of Hawai’i, could provide productive waters for fishing and, where large enough, nutrient-rich soils for cultivation. Indeed, archeological research on this tropical island chain has shown the ingenuity of past Hawaiian field systems that adapted to grow different cultivars and use different strategies on “leeward” (facing away from prevailing winds and often drier) and “windward” (facing toward prevailing winds and often wetter) sides of ridges. Complex systems of ancient aquaculture, in the form of stone-constructed pools, were also developed in Hawai’i to manage marine resources. Meanwhile, tiny coral atolls, like Pitcairn Island, had poor soils but vast reefs for fishing. Raised limestone, makatea islands, like those of the Solomon Islands, Fiji, and Tonga, had high levels of inland biodiversity, which, while potentially threatened by populations of humans and their animal companions, could also represent a significant resource if harnessed in the right way.13
Though shaped by their environments, these expanding human populations could also make their own decisions when the going got tough. Tikopia, an island of just 5 km2, was settled by people with Lapita pottery approximately 2,900 years ago. Over 2,000 years of forest clearing for the growth of yams and taro, the management of pigs and dogs, and the use of marine resources led to a drastic reduction in local biodiversity and forest cover and the increasing intensity of soil erosion on what was previously a fertile island. Around three hundred years ago, the local population decided enough was enough. They removed pigs and dogs from the island, managed forests instead of cutting them down, and eased pressure on vulnerable fish species. They also managed their population size. The result was relatively sustainable existence up to European colonization. Similarly, as noted above, the classic tale of Rapa Nui is usually one of human population explosion, complete deforestation, warfare, famine, and collapse by AD 1680, with stone faces of moai statues left behind on a now largely depopulated island as monuments to the overexploitation of resources. However, detailed archeobotanical analysis and renewed dating efforts have shown that, although humans and rats certainly did impact the forest between AD 1200 and 1650, this was not the whole story. From this point, the local population, which likely never grew to more than a few thousand, began using grass and ferns for fuel, stopped the creation of their iconic monuments, shifted to joint management of wild plants and domesticates, and persisted alongside some remnant tropical trees. The innovativeness of these populations can be seen in their use of mulch from volcanic rocks to supplement poor soils and their formation of underground manava gardens to protect their crops from wind and sea spray. In fact, it looks like it was actually the arrival of European colonizers on the island in AD 1722, with guns, diseases, and slavery, that led to the almost complete collapse of theretofore undoubtedly adaptable Indigenous Polynesian populations.14
THE EXPANSION OF Austronesian-language-speaking communities across the Pacific leads us to a surprising but neat segue into the final stop on our island tour, Africa’s coastal islands. Madagascar, one of the last large landmasses to be occupied by humans, sits around four hundred kilometers east of Mozambique. Remarkably, its modern Malagasy population has, among its ancestors, some of the same Austronesian speakers traveling through Southeast Asia who gave rise to the first settlers of Polynesia. In perhaps the single-greatest feat of seafaring in human history, beginning around 1,000 years ago, human populations from Indonesia, engaged in wider Indian Ocean trade networks, brought their language, crops, and genes all the way to the African continent. But we are getting ahead of ourselves. The timing of the first human settlement of Madagascar is, remarkably, not settled, and current suggestions range all the way from 10,500 to 1,200 years ago. The most recent detailed study, based on radiocarbon dates from a number of archeological sites, as well as clear evidence of butchered animal bones, suggests that humans were present by at least 2,000 years ago. Whatever the case, these first settlers are famous for a very different reason than the aforementioned Austronesian-language-speaking arrivals. Carrying stone tools from the African mainland and altering forests through burning, these groups have been linked to the disappearance of a variety of Madagascar’s enigmatic “megafauna,” including giant lemurs, humongous elephant birds, and native hippos. By 2,000 years ago, long prior to any intensive record of landscape burning, crop cultivation, and clear dense settlements, human activities—either direct hunting or indirect landscape changes—had possibly begun to have major implications for large animals across the spiny thickets, dry deciduous forests, and montane forests of Madagascar. By five hundred years ago, all wild animals larger than ten kilograms had disappeared from the island, which, back in the 1980s, served as a classic example of the “blitzkrieg” impacts of human hunting on megafaunal populations encountering humans for the first time.15
As Professor Kristina Douglass of the Pennsylvania State University, a seasoned explorer of Madagascar’s forests, explains, however, “The story is, once again, much more complicated than that.” Archeological sites have reported finds of giant lemurs and hippo bones with cutmarks from between 2,300 and 1,100 years ago in different parts of the island. Meanwhile, Kristina and her team have shown that prehistoric elephant bird eggs bear clear signs of human exploitation. Ultimately, though, these direct traces are few and far between. Peaks in deliberate human burning may have occurred at various times in the different biomes of the island between 1,700 and 1,100 years ago as populations expanded into different parts of the interior, though these changes seem to suggest a patchwork of human advance rather than a relentless frontier. Furthermore, even if the later dates of human occupation (c. 2,000 years ago) are taken, then human populations and megafauna coexisted without any obvious signs of decline for at least 1,000 years—longer if the earlier dates are accepted. Many of the large megafauna likely actually persisted on the island until at least 1,000 years ago. Not only that, but when these larger animals did begin to disappear, they did so in different ways and at different speeds across the hugely contrasting forest environments of Madagascar. As a result, it seems highly unlikely that human hunting alone eliminated Madagascar’s megafauna, with more complex, multifactor explanations, including recurring climatic variability and periods of drought, more probable.16
Figure 8.2. Artistic reconstruction of the now-extinct elephant birds of Madagascar. Velizar Simeonovski
A more recent “subsistence shift hypothesis” proposes that a change from a hunting and foraging lifestyle toward food production, notably pastoralism, imposed more sweeping, island-wide pressures on these Malagasy megafauna, particularly as populations expanded and Madagascar became part of enlarging Indian Ocean networks from around 1,000 years ago. Th
e first more permanent “residential” settlements appear from 1,300 years ago on the northeastern coast. In the next half millennium, villages moved to the interior as well as the shorelines, spanning from the eastern evergreen rainforests to the arid spiny bush of the southwest. Over approximately the same period, cattle and later goats arrived, and we see an increase in forest clearance and grassland presence across Madagascar as these key herd animals were left to overgraze and stop tree regrowth, as they do in many parts of Africa today. From seven hundred years ago, rice, the greater yam, and coconuts brought from Southeast Asia were grown in wetlands. Later, sorghum and cowpea from eastern Africa were used in more arid regions. These farming activities, alongside growing populations that began to produce elaborate settlements and hilltop fortifications, would certainly have increased the strain on native animals, perhaps even acting as the final tipping point for the disappearance of many endemic species by five hundred years ago against a backdrop of increased aridity. Nevertheless, as we have seen, different species declined at different rates and in different areas, with many on their way out prior to this point.17
In fact, the earliest food producers of Madagascar were remarkably resourceful. They combined the cultivation of incoming Southeast Asian and eastern African domesticates to different extents with the use of wild plant resources, depending on their environmental contexts and social situations. The same is seen across the other eastern African islands caught within a wider, flourishing Indian Ocean trading network. On near coastal islands, like Zanzibar and Pemba, Asian crops were typically rare relative to African millets, sorghum, and cowpea, with evidence of persistent hunting and fishing. In Madagascar itself, villages adapted to local contexts. Some practiced hillslope and wetland cultivation, while others preferred the herding of cattle and goats. Coastal communities focused on fishing, which still drives Malagasy economies and supplements farming diets today. Overgrazing and agricultural landscape transformations continue to increase soil erosion and deforestation and have helped make the remaining native lemurs some of the most threatened primates in the world. Yet, prior to five hundred years ago, human populations remained relatively small. So too did their herds of goat and cattle. The large-scale agricultural landscape modifications challenging sustainability on the island today only truly began following European arrival as colonizers and growing Indigenous polities grappled to control the increasingly contested tropical landscape.18
Turning to the opposite corner of the African continent, although the Canary Islands are just north of the Tropic of Cancer, their moist, marine climate supports extensive tropical and subtropical vegetation, and they provide another useful example for exploring prehistoric human impacts on island environments. The Canary Islands are a volcanic group of islands in the Atlantic Ocean just off the coast of northwestern Africa and include a number of favorite European holiday destinations. Their earliest human inhabitants, collectively known as the “Guanches” by later Spanish colonizers, arrived approximately 2,500 years ago. We now know that these first settlers, although previously characterized as stone-tool wielding foragers, had a rich toolkit of pottery, varied lithics, bone, leather, shell, wood, and other fibrous plants. Genetic, linguistic, and material comparisons indicate that these first inhabitants had a clear affinity to North African Berber populations and brought goats, sheep, pigs, and the trinity of dogs, cats, and mice with them to all of the Canary Islands. They also cultivated novel crops like barley, wheat, lentils, beans, figs, and peas carried from the mainland. As seen in Madagascar, and indeed in many of the islands we have touched upon so far, these farmers used fire to clear and open the landscapes for their introduced domesticates. This resulted in drastic reductions of forest cover and in “lost forests” in parts of islands or even across whole islands. Certain native tree species, like the laurels and the strawberry tree, disappeared on islands like Fuerteventura. Growing sheep and goat populations, on small islands, halted forest resurgence and led to soil erosion, while introduced mice and cats sent native rodents, large and small, into decline. Direct hunting also seems to have resulted in the demise of a large native lizard and a flightless quail.19
Scientists have suggested that, unlike on some of the other examples we have touched upon, a general lack of useful native plant resources and limited numbers of native large animals forced human arrivals to intensively pursue food production on the Canary Islands, with the corresponding consequences. Yet, again, the story is more complicated. A clear distinction can be seen between small, flat islands like Fuerteventura and Lanzarote, whose dry forest vegetation was more vulnerable to human clearance and all but disappeared, and the wetter of the small islands, like La Gomera and La Palma, and the larger islands of Tenerife and Gran Canaria, where forests remained standing upon European arrival. In the case of La Gomera, a sediment core collected from a former lake bed demonstrated that there was no clear signal of deforestation following the arrival of humans and that previous climate changes had led to greater forest disturbance. On La Palma, prehistoric humans changed their choice of tree species for fuel, recognizing the growing problem near their sites and venturing higher up into the mountains to ease the pressure. On Tenerife and Gran Canaria, the remaining forest regions might be seen as even more impressive given that these latter two islands had developed larger populations and a clear social hierarchy by the time European travelers coasted by their shores. Overall, the arrival of farming practices on the Canary Islands had stark consequences for local animals, plants, and landscape stability. The issues of deforestation and overgrazing still plague these islands today. Nevertheless, prior to European arrival, these impacts were dispersed and varied by island and location. As we will see in Chapters 10 and 11, Spanish colonization, ranching, and sugar manufacturing, driven by imperial demand, initiated truly sweeping changes across the archipelago, including perhaps local climatic shifts, that stay with its inhabitants to this day.20
TROPICAL ISLANDS HAVE often been thought of as ideal, isolated “laboratories” in which to study the impact of prehistoric human arrival on previously “pristine” ecosystems. While by no means a complete tour of all tropical islands, our trip around the Caribbean, the Pacific Islands, and the shores of Africa has shown us that hunting and gathering and, particularly, forms of farming practice can have major, lasting impacts on the native plants, animals, and landscapes of these often remote settings. Over the course of the Holocene, tropical islands have experienced a massive loss of endemic birds, amphibians, reptiles, and mammals, driven by human hunting, habitat change, and the invasive species humans brought along with them, either accidentally or deliberately. Rapid soil erosion and a loss of forest cover occurred as populations grew and farmers sought openings to plant more productive crops or societies sought new landmarks to differentiate status and act as cultural symbols. Entire ecosystems and environments could change, or even disappear, as new, economically useful plants were carried or promoted and others fell away. Beyond the land, overfishing and overuse of shellfish led to a dramatic reduction in their size and also to the shortening of marine food chains. These laboratories show us that prehistoric human impacts could leave a massive lasting impression on plants, animals, and entire island landscapes. Consequential changes to soils and available wild resources could also leave the settlers themselves facing an ultimatum of population collapse or island abandonment.
Nonetheless, the growing field of island archeology has also shown that these outcomes need not be inevitable and can indeed be averted through flexible decision making even in the most challenging of scenarios. Many of the societies we have met, including those that brought farming “packages” with them, adapted their lifestyles to their new situations or adapted the new situations to fit their lifestyles in what has become known as human “niche construction.” Some complemented their domesticate diets with local tropical forest plants and animals or fish from the reefs or deep blue seas off their island coasts. Some managed the local landscapes to ensure a
continuity of wild, native species alongside more tentative introductions. Where changes in ecosystem dynamics became obvious, groups could clearly also decide to rid themselves of domesticates and reduce deforestation, setting themselves on a new course toward sustainability. As a matter of fact, the starkest warning from these island examples is not that island environments were inherently vulnerable in the past and remain inherently vulnerable now. It is rather that in the past, populations were able to change their land use and their economies as they saw the landscape change around them. They noticed soils sliding, prey dwindling, and forests receding and could make decisions. Today, the forces of poverty, climate change, political priorities, and large industries wash up on island shores, staying the hands of the local inhabitants. As each example discussed above hints, the disruptive arrival of European empires and mercantile interests invariably brought these pressures of global consumer desires along with them, something we will explore in more detail in Chapters 10 and 11. However, before turning to the beginnings of a “globalization” that defines our current relationship with the tropics, it is worth first exploring the massive Indigenous urban societies that developed within tropical forests.21
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