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Tuesday, April 28, 2020

Pre-modern human migration

From Wikipedia, the free encyclopedia
Paleolithic migration prior to end of the Last Glacial Maximum spread anatomically modern humans throughout Afro-Eurasia and to the Americas. During the Holocene climatic optimum, formerly isolated populations began to move and merge, giving rise to the pre-modern distribution of the world's major language families.

In the wake of the population movements of the Mesolithic came the Neolithic revolution, followed by the Indo-European expansion in Eurasia and the Bantu expansion in Africa.

Population movements of the proto-historical or early historical period include the Migration period, followed by (or connected to) the Slavic, Magyar Norse, Turkic and Mongol expansions of the medieval period.

The last world regions to be permanently settled were the Pacific Islands and the Arctic, reached during the 1st millennium AD.

Since the beginning of the Age of Exploration and the beginning of the Early Modern period and its emerging colonial empires, an accelerated pace of migration on the intercontinental scale became possible.

Prehistory

Neolithic expansions from the 7th to the 5th millennium BC

Neolithic to Chalcolithic

Agriculture is believed to have first been practised around 10,000 BC in the Fertile Crescent (see Jericho). From there, it propagated as a "wave" across Europe, a view supported by Archaeogenetics, reaching northern Europe some 5 millennia ago. 

Some evidence (including a 2016 study by Busby et al.) suggests admixture from an ancient migration from Eurasia into parts of Sub-Saharan Africa. Another study (Ramsay et al. 2018) also shows evidence that ancient Eurasians migrated into Africa and that Eurasian admixture in modern Sub-Saharan Africans ranges from 0% to 50%, varying by region and generally highest (after North Africa) in the Horn of Africa and parts of the Sahel zone.

Bronze Age

Scheme of Indo-European migrations from c. 4000 to 1000 BC according to the Kurgan hypothesis. The purple area corresponds to the assumed Urheimat (Samara culture, Sredny Stog culture). The red area corresponds to the area which may have been settled by Indo-European-speaking peoples up to c. 2500 BC; the orange area to 1000 BC.
 
The proposed Indo-European migration has variously been dated to the end of the Neolithic (Marija Gimbutas: Corded Ware culture, Yamna culture, Kurgan culture), the early Neolithic (Colin Renfrew: Starčevo-Körös, Linearbandkeramic) and the late Palaeolithic (Marcel Otte, Paleolithic Continuity Theory).

The speakers of the Proto-Indo-European language are usually believed to have originated to the North of the Black Sea (today Eastern Ukraine and Southern Russia), and from there they gradually migrated into, and spread their language by cultural diffusion to, Anatolia, Europe, and Central Asia Iran and South Asia starting from around the end of the Neolithic period. Other theories, such as that of Colin Renfrew, posit their development much earlier, in Anatolia, and claim that Indo-European languages and culture spread as a result of the agricultural revolution in the early Neolithic.

Relatively little is known about the inhabitants of pre-Indo-European "Old Europe". The Basque language remains from that era, as do the indigenous languages of the Caucasus. The Sami are genetically distinct among the peoples of Europe, but the Sami languages, as part of the Uralic languages, spread into Europe about the same time as the Indo-European languages. However, since that period speakers of other Uralic languages such as the Finns and the Estonians have had more contact with other Europeans, thus today sharing more genes with them than the Sami.

The earliest migrations we can reconstruct from historical sources are those of the 2nd millennium BC. The Proto-Indo-Iranians began their expansion from c. 2000 BC, the Rigveda documenting the presence of early Indo-Aryans in the Punjab from the late 2nd millennium BC, and Iranian tribes being attested in Assyrian sources as in the Iranian plateau from the 9th century BC. In the Late Bronze Age, the Aegean and Anatolia were overrun by moving populations, summarized as the "Sea Peoples", leading to the collapse of the Hittite Empire and ushering in the Iron Age.

Austronesian expansion

Austronesians expansion map

The islands of the Pacific were populated during c. 1600 BC and AD 1000. The Lapita people, who got their name from the archaeological site in Lapita, New Caledonia, where their characteristic pottery was first discovered, came from Austronesia, probably New Guinea, reaching the Solomon Islands, around 1600 BC, and later to Fiji, Samoa and Tonga. By the beginning of the 1st millennium BC, most of Polynesia was a loose web of thriving cultures who settled on the islands' coasts and lived off the sea. By 500 BC Micronesia was completely colonized; the last region of Polynesia to be reached was New Zealand in around 1000.

Celtic expansion in Europe, 6th–3rd century BC

Bantu expansion

The Bantu expansion is the major prehistoric migratory pattern that shaped the ethno-linguistic composition of Sub-Saharan Africa.

The Bantu, a branch of the Niger-Congo phylum, originated in West Africa around the Benue-Cross rivers area in southeastern Nigeria. Beginning in the 2nd millennium BC, they spread to Central Africa, and later, during the 1st millennium BC onward southeastern, spreading pastoralism and agriculture. During the 1st millennium AD, they populated Southern African. In the process, the Bantu languages displaced the Khoisan languages indigenous to Central and Southern Africa.

Arctic peoples

The final region to be permanently settled by humans was the Arctic, reached by the Dorset culture during about 500 BC to AD 1500. The Inuit are the descendants of the Thule culture, which emerged from western Alaska around AD 1000 and gradually displaced the Dorset culture.

Proto-historical and early historical migration

Map of Phoenician (in yellow) and Greek colonies (in red) around 8th to 6th century BC
 
Map showing the southward migration of the Han Chinese (in blue)
 
The German term Landnahme ("land-taking") is sometimes used in historiography for a migration event associated with a founding legend, e.g. of the conquest of Canaan in the Hebrew Bible, the Indo-Aryan migration and expansion within India alluded to in the Rigveda, the invasion traditions in the Irish Mythological Cycle, accounting for how the Gaels came to Ireland the arrival of the Franks in Austrasia during the Migration period, the Anglo-Saxon invasion of Britain, the settlement of Iceland in the Viking Age, the Slavic migrations, the Hungarian conquest , etc.

Iron Age

The Dorian invasion of Greece led to the Greek Dark Ages. The Urartians were displaced by Armenians, and the Cimmerians and the Mushki migrated from the Caucasus into Anatolia. A Thraco-Cimmerian connection links these movements to the Proto-Celtic world of central Europe, leading to the introduction of Iron to Europe and the Celtic expansion to western Europe and the British Isles around 500 BC.

Migration period

2nd to 5th century migrations. See also map of the world in 820.
 
Migration of Slavic peoples in the 5th to 10th centuries.
 
Western historians refer to the period of migrations that separated Antiquity from the Middle Ages in Europe as the Great Migrations or as the Migrations Period. This period is further divided into two phases.

The first phase, from 300 to 500, saw the movement of Germanic, Sarmatian and Hunnic tribes and ended with the settlement of these peoples in the areas of the former Western Roman Empire. (See also: Ostrogoths, Visigoths, Burgundians, Suebi, Alamanni, Marcomanni).

The second phase, between 500 and 900, saw Slavic, Turkic and other tribes on the move, re-settling in Eastern Europe and gradually making it predominantly Slavic. Moreover, more Germanic tribes migrated within Europe during this period, including the Lombards (to Italy), and the Angles, Saxons, and Jutes (to the British Isles). See also: Avars, Bulgars, Huns, Arabs, Vikings, Varangians. The last phase of the migrations saw the coming of the Hungarians to the Pannonian plain.

German historians of the 19th century referred to these Germanic migrations as the Völkerwanderung, the migrations of the peoples.

The European migration period is connected with the simultaneous Turkic expansion which at first displaced other peoples towards the west, and by High Medieval times, the Seljuk Turks themselves reached the Mediterranean.

Early medieval period

The medieval period, although often presented as a time of limited human mobility and slow social change in the history of Europe, in fact saw widespread movement of peoples. The Vikings from Scandinavia raided all over Europe from the 8th century and settled in many places, including Normandy, the north of England, Scotland and Ireland (most of whose urban centres were founded by the Vikings). The Normans later conquered the Saxon Kingdom of England, most of Ireland, southern Italy and Sicily

Iberia was invaded by Muslim Arabs, Berbers and Moors in the 8th century, founding new Kingdoms such as al Andalus and bringing with them a wave of settlers from North Africa. The invasion of North Africa by the Banu Hilal, a warlike Arab Bedouin tribe, was a major factor in the linguistic, cultural Arabization of the Maghreb.

Late Middle Ages

Massive migrations of Germans took place into East Central and Eastern Europe, reaching its peak in the 12th to 14th centuries. These Ostsiedlung settlements in part followed territorial gains of the Holy Roman Empire, but areas beyond were settled, too.

At the end of the Middle Ages, the Romani (gypsies) arrived in Europe from the Middle East. They originate in India, probably an offshoot of the Domba people of Northern India who had left for Sassanid Persia around the 5th century.

Early Modern period

Map of Vietnam showing the conquest of the south (the Nam tiến, 1069–1757).

Early Modern Europe

Internal European migration stepped up in the Early Modern Period. In this period, major migration within Europe included the recruiting by monarchs of landless laborers to settle depopulated or uncultivated regions and a series of forced migration caused by religious persecution. Notable examples of this phenomenon include the expulsion of the Jews from Spain in 1492, mass migration of Protestants from the Spanish Netherlands to the Dutch Republic after the 1580s, the expulsion of the Moriscos (descendants of former Muslims) from Spain in 1609, and the expulsion of the Huguenots from France in the 1680s. Since the 14th century, the Serbs started leaving the areas of their medieval Kingdom and Empire that was overrun by the Ottoman Turks and migrated to the north, to the lands of today's Vojvodina (northern Serbia), which was ruled by the Kingdom of Hungary at that time. The Habsburg monarchs of Austria encouraged them to settle on their frontier with the Turks and provide military service by granting them free land and religious toleration. The two greatest migrations took place in 1690 and 1737. Other instances of labour recruitments include the Plantations of Ireland - the settling of Ireland with Protestant colonists from England, Scotland and Wales in the period 1560–1690 and the recruitment of Germans by Catherine the Great of Russia to settle the Volga region in the 18th century.

Colonial empires

European Colonialism from the 16th to the early 20th centuries led to an imposition of a European colonies in many regions of the world, particularly in the Americas, South Asia, Sub-Saharan Africa and Australia, where European languages remain either prevalent or in frequent use as administrative languages. Major human migration before the 18th century was largely state directed. For instance, Spanish emigration to the New World was limited to settlers from Castile who were intended to act as soldiers or administrators. Mass immigration was not encouraged due to a labour shortage in Europe (of which Spain was the worst affected by a depopulation of its core territories in the 17th century).

Europeans also tended to die of tropical diseases in the New World in this period and for this reason England, France and Spain preferred using slaves as free labor in their American possessions. Many historians attribute a change in this pattern in the 18th century to population increases in Europe.

However, in the less tropical regions of North America's east coast, large numbers of religious dissidents, mostly English Puritans, settled during the early 17th century. Spanish restrictions on emigration to Latin America were revoked and the English colonies in North America also saw a major influx of settlers attracted by cheap or free land, economic opportunity and the continued lure of religious toleration.

A period in which various early English colonies had a significant amount of self-rule prevailed from the time of the Plymouth colony's founding in 1620 through 1676, as the mother country was wracked by revolution and general instability. However, King William III decisively intervened in colonial affairs after 1688 and the English colonies gradually came more directly under royal governance, with a marked effect on the type of emigration. During the early 18th century, significant numbers of non-English seekers of greater religious and political freedom were allowed to settle within the British colonies, including Protestant Palatine Germans displaced by French conquest, French Huguenots disenfranchised by an end of religious tolerance, Scotch-Irish Presbyterians, Quakers who were often Welsh, as well as Presbyterian and Catholic Scottish Highlanders seeking a new start after a series of unsuccessful revolts.

Map of colonial empires throughout the world in 1754, prior to the Seven Years' War
 
The English colonists who came during this period were increasingly moved by economic necessity. Some colonies, including Georgia, were settled heavily by petty criminals and indentured servants who hoped to pay off their debts. By 1800, European emigration had transformed the demographic character of the American continent. This was also due in part to the devastating effect of European diseases and warfare on Native American populations.

The European settlers' influence elsewhere was less pronounced as in South Asia and Africa. European settlement in this period was limited to a thin layer of administrators, traders and soldiers.

Monday, April 27, 2020

Settlement of the Americas

From Wikipedia, the free encyclopedia
Map of the earliest securely dated sites showing human presence in the Americas, 16–13 ka for North America and 15–11 ka for South America.

The settlement of the Americas began when Paleolithic hunter-gatherers entered North America from the North Asian Mammoth steppe via the Beringia land bridge, which had formed between northeastern Siberia and western Alaska due to the lowering of sea level during the Last Glacial Maximum. These populations expanded south of the Laurentide Ice Sheet and spread rapidly throughout both North and South America, by 14,000 years ago. The earliest populations in the Americas, before roughly 10,000 years ago, are known as Paleo-Indians

The peopling of the Americas is a long-standing open question, and while advances in archaeology, Pleistocene geology, physical anthropology, and DNA analysis have shed progressively more light on the subject, significant questions remain unresolved. While there is general agreement that the Americas were first settled from Asia, the pattern of migration, its timing, and the place(s) of origin in Eurasia of the peoples who migrated to the Americas remain unclear.

The prevalent migration models outline different time frames for the Asian migration from the Bering Straits and subsequent dispersal of the founding population throughout the continent. Indigenous peoples of the Americas have been linked to Siberian populations by linguistic factors, the distribution of blood types, and in genetic composition as reflected by molecular data, such as DNA.

The "Clovis first theory" refers to the 1950s hypothesis that the Clovis culture represents the earliest human presence in the Americas, beginning about 13,000 years ago; evidence of pre-Clovis cultures has accumulated since 2000, pushing back the possible date of the first peopling of the Americas to about 13,200–15,500 years ago.

The environment during the latest glaciation

Emergence and submergence of Beringia

Figure1. Submergence of the Beringian land bridge with post-Last Glacial Maximum (LGM) rise in eustatic sea level

During the Wisconsin glaciation, the Earth's ocean water was, to varying degrees over time, stored in glacier ice. As water accumulated in glaciers, the volume of water in the oceans correspondingly decreased, resulting in lowering of global sea level. The variation of sea level over time has been reconstructed using oxygen isotope analysis of deep sea cores, the dating of marine terraces, and high resolution oxygen isotope sampling from ocean basins and modern ice caps. A drop of eustatic sea level by about 60 to 120 metres (200 to 390 ft) lower than present-day levels, commencing around 30,000 years BP, created Beringia, a durable and extensive geographic feature connecting Siberia with Alaska. With the rise of sea level after the Last Glacial Maximum (LGM), the Beringian land bridge was again submerged. Estimates of the final re-submergence of the Beringian land bridge based purely on present bathymetry of the Bering Strait and eustatic sea level curve place the event around 11,000 years BP (Figure 1). Ongoing research reconstructing Beringian paleogeography during deglaciation could change that estimate and possible earlier submergence could further constrain models of human migration into North America.

Glaciers

The onset of the Last Glacial Maximum after 30,000 years BP saw the expansion of alpine glaciers and continental ice sheets that blocked migration routes out of Beringia. By 21,000 years BP, and possibly thousands of years earlier, the Cordilleran and Laurentide ice sheets coalesced east of the Rocky Mountains, closing off a potential migration route into the center of North America. Alpine glaciers in the coastal ranges and the Alaskan Peninsula isolated the interior of Beringia from the Pacific coast. Coastal alpine glaciers and lobes of Cordilleran ice coalesced into piedmont glaciers that covered large stretches of the coastline as far south as Vancouver Island and formed an ice lobe across the Straits of Juan de Fuca by 15,000 14C years BP (18,000 cal years BP). Coastal alpine glaciers started to retreat around 19,000 cal years BP  while Cordilleran ice continued advancing in the Puget lowlands up to 14,000 14C years BP (16,800 cal years BP) Even during the maximum extent of coastal ice, unglaciated refugia persisted on present-day islands, that supported terrestrial and marine mammals. As deglaciation occurred, refugia expanded until the coast became ice-free by 15,000 cal years BP. The retreat of glaciers on the Alaskan Peninsula provided access from Beringia to the Pacific coast by around 17,000 cal years BP. The ice barrier between interior Alaska and the Pacific coast broke up starting around 13,500 14C years (16,200 cal years) BP. The ice-free corridor to the interior of North America opened between 13,000 and 12,000 cal years BP. Glaciation in eastern Siberia during the LGM was limited to alpine and valley glaciers in mountain ranges and did not block access between Siberia and Beringia.

Climate and biological environments

The paleoclimates and vegetation of eastern Siberia and Alaska during the Wisconsin glaciation have been deduced from high resolution oxygen isotope data and pollen stratigraphy. Prior to the Last Glacial Maximum, climates in eastern Siberia fluctuated between conditions approximating present day conditions and colder periods. The pre-LGM warm cycles in Arctic Siberia saw flourishes of megafaunas. The oxygen isotope record from the Greenland Ice Cap suggests that these cycles after about 45k years BP lasted anywhere from hundreds to between one and two thousand years, with greater duration of cold periods starting around 32k cal years BP. The pollen record from Elikchan Lake, north of the Sea of Okhotsk, shows a marked shift from tree and shrub pollen to herb pollen prior to 26k 14C years BP, as herb tundra replaced boreal forest and shrub steppe going into the LGM. A similar record of tree/shrub pollen being replaced with herb pollen as the LGM approached was recovered near the Kolyma River in Arctic Siberia. The abandonment of the northern regions of Siberia due to rapid cooling or the retreat of game species with the onset of the LGM has been proposed to explain the lack of archaeosites in that region dating to the LGM. The pollen record from the Alaskan side shows shifts between herb/shrub and shrub tundra prior to the LGM, suggesting less dramatic warming episodes than those that allowed forest colonization on the Siberian side. Diverse, though not necessarily plentiful, megafaunas were present in those environments. Herb tundra dominated during the LGM, due to cold and dry conditions.

Coastal environments during the Last Glacial Maximum were complex. The lowered sea level, and an isostatic bulge equilibrated with the depression beneath the Cordilleran Ice Sheet, exposed the continental shelf to form a coastal plain. While much of the coastal plain was covered with piedmont glaciers, unglaciated refugia supporting terrestrial mammals have been identified on Haida Gwaii, Prince of Wales Island, and outer islands of the Alexander Archipelago. The now-submerged coastal plain has potential for more refugia. Pollen data indicate mostly herb/shrub tundra vegetation in unglaciated areas, with some boreal forest towards the southern end of the range of Cordilleran ice. The coastal marine environment remained productive, as indicated by fossils of pinnipeds. The highly productive kelp forests over rocky marine shallows may have been a lure for coastal migration. Reconstruction of the southern Beringian coastline also suggests potential for a highly productive coastal marine environment.

Environmental changes during deglaciation

Pollen data indicate a warm period culminating between 14k and 11k 14C years BP (17k-13k cal years BP) followed by cooling between 11k-10k 14C years BP (13k-11.5k cal years BP).[23] Coastal areas deglaciated rapidly as coastal alpine glaciers, then lobes of Cordilleran ice, retreated. The retreat was accelerated as sea levels rose and floated glacial termini. Estimates of a fully ice-free coast range between 16k and 15k cal years BP. Littoral marine organisms colonized shorelines as ocean water replaced glacial meltwater. Replacement of herb/shrub tundra by coniferous forests was underway by 12.4k 14C years BP (15k cal years BP) north of Haida Gwaii. Eustatic sea level rise caused flooding, which accelerated as the rate grew more rapid.

The inland Cordilleran and Laurentide ice sheets retreated more slowly than did the coastal glaciers. Opening of an ice-free corridor did not occur until after 13k to 12k cal years BP. The early environment of the ice-free corridor was dominated by glacial outwash and meltwater, with ice-dammed lakes and periodic flooding from the release of ice-dammed meltwater. Biological productivity of the deglaciated landscape was gained slowly. The earliest possible viability of the ice-free corridor as a human migration route has been estimated at 11.5k cal years BP.

Birch forests were advancing across former herb tundra in Beringia by 14.3ka 14C years BP (17k cal years BP) in response to climatic amelioration, indicating increased productivity of the landscape.

Chronology, reasons for, and sources of migration

25,000 years ago Beringia during the LGM 16-14,000 years ago peopling of the Americas just after the LGM
 
The archaeological community is in general agreement that the ancestors of the Indigenous peoples of the Americas of historical record entered the Americas at the end of the Last Glacial Maximum (LGM), shortly after 20,000 years ago, with ascertained archaeological presence shortly after 16,000 years ago. 

There remain uncertainties regarding the precise dating of individual sites and regarding conclusions drawn from population genetics studies of contemporary Native Americans. It is also an open question whether this post-LGM migration represented the first peopling of the Americas, or whether there had been an earlier, pre-LGM migration which had reached South America as early as 40,000 years ago.

Chronology

In the early 21st century, the models of the chronology of migration are divided into two general approaches.

The first is the short chronology theory, that the first migration occurred after the Last Glacial Maximum, which went into decline after about 19,000 years ago, and was then followed by successive waves of immigrants.

The second theory is the long chronology theory, which proposes that the first group of people entered the Americas at a much earlier date, possibly before 40,000 years ago, followed by a much later second wave of immigrants.

The Clovis First theory, which dominated thinking on New World anthropology for much of the 20th century, was challenged by the secure dating of archaeosites in the Americas to before 13,000 years ago in the 2000s. The "short chronology" scenario, in the light of this, refers to a peopling of the Americas shortly after 19,000 years ago, while the "long chronology" scenario permits pre-LGM presence, by around 40,000 years ago. 

The archaeosites in the Americas with the oldest dates that have gained broad acceptance are all compatible with an age of about 15,000 years. This includes the Buttermilk Creek Complex in Texas, the Meadowcroft Rockshelter site in Pennsylvania and the Monte Verde site in southern Chile. Archaeological evidence of pre-Clovis people points to the South Carolina Topper Site being 16,000 years old, at a time when the glacial maximum would have theoretically allowed for lower coastlines.
It has often been suggested that an ice-free corridor, in what is now Western Canada, would have allowed migration before the beginning of the Holocene, but a 2016 study has argued against this, suggesting that the peopling of North America via such a corridor is unlikely to significantly pre-date the earliest Clovis sites. The study concludes that the ice-free corridor in what is now Alberta and British Columbia "was gradually taken over by a boreal forest dominated by spruce and pine trees" and that the "Clovis people likely came from the south, not the north, perhaps following wild animals such as bison". An alternative hypothesis for the peopling of America is coastal migration, which may have been feasible along the deglaciated (but now submerged) coastline of the Pacific Northwest from about 16,000 years ago.

Evidence for pre-LGM human presence

Schematic illustration of maternal geneflow in and out of Beringia.Colours of the arrows correspond to approximate timing of the events and are decoded in the coloured time-bar. The initial peopling of Berinigia (depicted in light yellow) was followed by a standstill after which the ancestors of indigenous Americans spread swiftly all over the New World, while some of the Beringian maternal lineages–C1a-spread westwards. More recent (shown in green) genetic exchange is manifested by back-migration of A2a into Siberia and the spread of D2a into north-eastern America that post-dated the initial peopling of the New World.
Figure 2. Schematic illustration of maternal (mtDNA) gene-flow in and out of Beringia (long chronology, single source model).
 
"Maps depicting each phase of the three-step early human migrations for the peopling of the Americas. (A) Gradual population expansion of the Amerind ancestors from their Central East Asian gene pool (blue arrow). (B) Proto-Amerind occupation of Beringia with little to no population growth for ≈20,000 years. (C) Rapid colonization of the New World by a founder group migrating southward through the ice-free, inland corridor between the eastern Laurentide and western Cordilleran Ice Sheets (green arrow) and/or along the Pacific coast (red arrow). In (B), the exposed seafloor is shown at its greatest extent during the last glacial maximum at ≈20–18,000 years ago [25]. In (A) and (C), the exposed seafloor is depicted at ≈40,000 years ago and ≈16,0000 years ago, when prehistoric sea levels were comparable. A scaled-down version of Beringia today (60% reduction of A–C) is presented in the lower left corner. This smaller map highlights the Bering Strait that has geographically separated the New World from Asia since ≈11–10,000 years ago."
Map of Beringia showing the exposed seafloor and glaciation at 40,000 years ago and 16,000 years ago. The green arrow indicates the "interior migration" model along an ice-free corridor separating the major continental ice sheets, the red arrow indicates the "coastal migration" model, both leading to a "rapid colonization" of the Americas after c. 16,000 years ago.
 
Pre-Last Glacial Maximum migration across Beringia into the Americas has been proposed to explain purported pre-LGM ages of archaeosites in the Americas such as Bluefish Caves and Old Crow Flats in the Yukon Territory, and Meadowcroft Rock Shelter in Pennsylvania.

At the Old Crow Flats, mammoth bones have been found that are broken in distinctive ways indicating human butchery. The radiocarbon dates on these vary between 25,000 and 40,000 years BP. Also, stone microflakes have been found in the area indicating tool production.

Previously, the interpretations of butcher marks and the geologic association of bones at the Bluefish Cave and Old Crow Flats sites, and the related Bonnet Plume site, have been called into question.
Pre-LGM human presence in South America rests partly on the chronology of the controversial Pedra Furada rock shelter in Piauí, Brazil. A 2003 study dated evidence for the controlled use of fire to before 40,000 years ago. Additional evidence has been adduced from the morphology of Luzia Woman fossil, which was described as Australoid. This interpretation was challenged in a 2003 review which concluded the features in question could also have arisen by genetic drift.

The ages of the earliest positively identified artifacts at the Meadowcroft site are safely within the post-LGM period (13.8k–18.5k cal years BP).

Stones described as probable tools, hammerstones and anvils, have been found in southern California, at the Cerutti Mastodon site, that are associated with a mastodon skeleton which appeared to have been processed by humans. The mastodon skeleton was dated by thorium-230/uranium radiometric analysis, using diffusion–adsorption–decay dating models, to 130.7 ± 9.4 thousand years ago.[44] No human bones were found, and the claims of tools and bone processing have been described as "not plausible".
The Yana River Rhino Horn site (RHS) has dated human occupation of eastern Arctic Siberia to 27k 14C years BP (31.3k cal years BP). That date has been interpreted by some as evidence that migration into Beringia was imminent, lending credence to occupation of Beringia during the LGM. However, the Yana RHS date is from the beginning of the cooling period that led into the LGM. But, a compilation of archaeosite dates throughout eastern Siberia suggest that the cooling period caused a retreat of humans southwards. Pre-LGM lithic evidence in Siberia indicate a settled lifestyle that was based on local resources, while post-LGM lithic evidence indicate a more migratory lifestyle.

The oldest archaeosite on the Alaskan side of Beringia date to 12k 14C years BP (14k cal years BP). It is possible that a small founder population had entered Beringia before that time. However, archaeosites that date closer to the Last Glacial Maximum on either the Siberian or the Alaskan side of Beringia are lacking.

Genomic age estimates

Studies of Amerindian genetics have used high resolution analytical techniques applied to DNA samples from modern Native Americans and Asian populations regarded as their source populations to reconstruct the development of human Y-chromosome DNA haplogroups (yDNA haplogroups) and human mitochondrial DNA haplogroups (mtDNA haplogroups) characteristic of Native American populations. Models of molecular evolution rates were used to estimate the ages at which Native American DNA lineages branched off from their parent lineages in Asia and to deduce the ages of demographic events. One model (Tammetal 2007) based on Native American mtDNA Haplotypes (Figure 2) proposes that migration into Beringia occurred between 30k and 25k cal years BP, with migration into the Americas occurring around 10k to 15k years after isolation of the small founding population. Another model (Kitchen et al. 2008) proposes that migration into Beringia occurred approximately 36k cal years BP, followed by 20k years of isolation in Beringia. A third model (Nomatto et al. 2009) proposes that migration into Beringia occurred between 40k and 30k cal years BP, with a pre-LGM migration into the Americas followed by isolation of the northern population following closure of the ice-free corridor. Evidence of Australo-Melanesians admixture in Amazonian populations was found by Skoglund and Reich (2016).

A study of the diversification of mtDNA Haplogroups C and D from southern Siberia and eastern Asia, respectively, suggests that the parent lineage (Subhaplogroup D4h) of Subhaplogroup D4h3, a lineage found among Native Americans and Han Chinese, emerged around 20k cal years BP, constraining the emergence of D4h3 to post-LGM. Age estimates based on Y-chromosome micro-satellite diversity place origin of the American Haplogroup Q1a3a (Y-DNA) at around 10k to 15k cal years BP. Greater consistency of DNA molecular evolution rate models with each other and with archaeological data may be gained by the use of dated fossil DNA to calibrate molecular evolution rates.

Source populations

There is general agreement among anthropologists that the source populations for the migration into the Americas originated from an area somewhere east of the Yenisei River (Russian Far East). The common occurrence of the mtDNA Haplogroups A, B, C, and D among eastern Asian and Native American populations has long been recognized, along with the presence of haplogroup X. As a whole, the greatest frequency of the four Native American associated haplogroups occurs in the Altai-Baikal region of southern Siberia. Some subclades of C and D closer to the Native American subclades occur among Mongolian, Amur, Japanese, Korean, and Ainu populations.

A 2019 study suggested that Native Americans are the closest living relatives to 10,000-year-old fossils found near the Kolyma River in northeastern Siberia.

Human genomic models

The development of high-resolution genomic analysis has provided opportunities to further define Native American subclades and narrow the range of Asian subclades that may be parent or sister subclades. For example, the broad geographic range of haplogroup X has been interpreted as allowing the possibility of a western Eurasian, or even a European source population for Native Americans, as in the Solutrean hypothesis, or suggesting a pre-Last Glacial Maximum migration into the Americas. The analysis of an ancient variant of haplogroup X among aboriginals of the Altai region indicates common ancestry with the European strain rather than descent from the European strain. Further division of X subclades has allowed identification of subhaplogroup X2a, which is regarded as specific to Native Americans. With further definition of subclades related to Native American populations, the requirements for sampling Asian populations to find the most closely related subclades grow more specific. Subhaplogroups D1 and D4h3 have been regarded as Native American specific based on their absence among a large sampling of populations regarded as potential descendants of source populations, over a wide area of Asia. Among the 3764 samples, the Sakhalin – lower Amur region was represented by 61 Oroks. In another study, Subhaplogroup D1a has been identified among the Ulchis of the lower Amur River region (4 among 87 sampled, or 4.6%), along with Subhaplogroup C1a (1 among 87, or 1.1%). Subhaplogroup C1a is regarded as a close sister clade of the Native American Subhaplogroup C1b.

Subhaplogroup D1a has also been found among ancient Jōmon skeletons from Hokkaido The modern Ainu are regarded as descendants of the Jōmon. The occurrence of the Subhaplogroups D1a and C1a in the lower Amur region suggests a source population from that region distinct from the Altai-Baikal source populations, where sampling did not reveal those two particular subclades. The conclusions regarding Subhaplogroup D1 indicating potential source populations in the lower Amur and Hokkaido areas stand in contrast to the single-source migration model.

Subhaplogroup D4h3 has been identified among Han Chinese. Subhaplogroup D4h3 from China does not have the same geographic implication as Subhaplotype D1a from Amur-Hokkaido, so its implications for source models are more speculative. Its parent lineage, Subhaplotype D4h, is believed to have emerged in east Asia, rather than Siberia, around 20k cal years BP. Subhaplogroup D4h2, a sister clade of D4h3, has also been found among Jōmon skeletons from Hokkaido. D4h3 has a coastal trace in the Americas.

The contrast between the genetic profiles of the Hokkaido Jōmon skeletons and the modern Ainu illustrates another uncertainty in source models derived from modern DNA samples:
However, probably due to the small sample size or close consanguinity among the members of the site, the frequencies of the haplogroups in Funadomari skeletons were quite different from any modern populations, including Hokkaido Ainu, who have been regarded as the direct descendant of the Hokkaido Jōmon people.
The descendants of source populations with the closest relationship to the genetic profile from the time when differentiation occurred are not obvious. Source population models can be expected to become more robust as more results are compiled, the heritage of modern proxy candidates becomes better understood, and fossil DNA in the regions of interest is found and considered.

HTLV-1 genomics

The Human T cell Lymphotrophic Virus 1 (HTLV-1) is a virus transmitted through exchange of bodily fluids and from mother to child through breast milk. The mother-to-child transmission mimics a hereditary trait, although such transmission from maternal carriers is less than 100%. The HTLV virus genome has been mapped, allowing identification of four major strains and analysis of their antiquity through mutations. The highest geographic concentrations of the strain HLTV-1 are in sub-Saharan Africa and Japan. In Japan, it occurs in its highest concentration on Kyushu. It is also present among African descendants and native populations in the Caribbean region and South America. It is rare in Central America and North America. Its distribution in the Americas has been regarded as due to importation with the slave trade.

The Ainu have developed antibodies to HTLV-1, indicating its endemicity to the Ainu and its antiquity in Japan. A subtype "A" has been defined and identified among the Japanese (including Ainu), and among Caribbean and South American isolates. A subtype "B" has been identified in Japan and India. In 1995, Native Americans in coastal British Columbia were found to have both subtypes A and B. Bone marrow specimens from an Andean mummy about 1500 years old were reported to have shown the presence of the A subtype. The finding ignited controversy, with contention that the sample DNA was insufficiently complete for the conclusion and that the result reflected modern contamination. However, a re-analysis indicated that the DNA sequences were consistent with, but not definitely from, the "cosmopolitan clade" (subtype A). The presence of subtypes A and B in the Americas is suggestive of a Native American source population related to the Ainu ancestors, the Jōmon.

Physical anthropology

Paleoamerican skeletons in the Americas such as Kennewick Man (Washington State), Hoya Negro skeleton (Yucatán), Luzia Woman and other skulls from the Lagoa Santa site (Brazil), Buhl Woman (Idaho), Peñon Woman III, two skulls from the Tlapacoya site (Mexico City), and 33 skulls from Baja California have exhibited craniofacial traits distinct from most modern Native Americans, leading physical anthropologists to the opinion that some Paleoamericans were of an Australoid rather than Siberian origin. The most basic measured distinguishing trait is the dolichocephaly of the skull. Some modern isolates such as the Pericúes of Baja California and the Fuegians of Tierra del Fuego exhibit that same morphological trait. Other anthropologists advocate an alternative hypothesis that evolution of an original Beringian phenotype gave rise to a distinct morphology that was similar in all known Paleoamerican skulls, followed by later convergence towards the modern Native American phenotype. Resolution of the issue awaits the identification of a Beringian phenotype among paleoamerican skulls or evidence of a genetic clustering among examples of the Australoid phenotype. 

A report published in the American Journal of Physical Anthropology in January 2015 reviewed craniofacial variation focussing on differences between early and late Native Americans and explanations for these based on either skull morphology or molecular genetics. Arguments based on molecular genetics have in the main, according to the authors, accepted a single migration from Asia with a probable pause in Berengia, plus later bi-directional gene flow. Studies focussing on craniofacial morphology have argued that Paleoamerican remains have "been described as much closer to African and Australo-Melanesians populations than to the modern series of Native Americans", suggesting two entries into the Americas, an early one occurring before a distinctive East Asian morphology developed (referred to in the paper as the "Two Components Model". A third model, the "Recurrent Gene Flow" [RGF] model, attempts to reconcile the two, arguing that circumarctic gene flow after the initial migration could account for morphological changes. It specifically re-evaluates the original report on the Hoya Negro skeleton which supported the RGF model, the authors disagreed with the original conclusion which suggested that the skull shape did not match those of modern Native Americans, arguing that the "skull falls into a subregion of the morphospace occupied by both Paleoamericans and some modern Native Americans."

Stemmed points

Stemmed points are a lithic technology distinct from Beringian and Clovis types. They have a distribution ranging from coastal east Asia to the Pacific coast of South America. The emergence of stemmed points has been traced to Korea during the upper Paleolithic. The origin and distribution of stemmed points have been interpreted as a cultural marker related to a source population from coastal east Asia.

Migration routes

Interior route

Map showing the approximate location of the ice-free corridor along the Continental Divide, separating the Cordilleran and Laurentide ice sheets. Also indicated are the locations of the Clovis and Folsom Paleo-Indian sites.
 
Historically, theories about migration into the Americas have centered on migration from Beringia through the interior of North America. The discovery of artifacts in association with Pleistocene faunal remains near Clovis, New Mexico in the early 1930s required extension of the timeframe for the settlement of North America to the period during which glaciers were still extensive. That led to the hypothesis of a migration route between the Laurentide and Cordilleran ice sheets to explain the early settlement. The Clovis site was host to a lithic technology characterized by spear points with an indentation, or flute, where the point was attached to the shaft. A lithic complex characterized by the Clovis Point technology was subsequently identified over much of North America and in South America. The association of Clovis complex technology with late Pleistocene faunal remains led to the theory that it marked the arrival of big game hunters that migrated out of Beringia then dispersed throughout the Americas, otherwise known as the Clovis First theory. 

Recent radiocarbon dating of Clovis sites has yielded ages of 11.1k to 10.7k 14C years BP (13k to 12.6k cal years BP), somewhat later than dates derived from older techniques. The re-evaluation of earlier radiocarbon dates led to the conclusion that no fewer than 11 of the 22 Clovis sites with radiocarbon dates are "problematic" and should be disregarded, including the type site in Clovis, New Mexico. Numerical dating of Clovis sites has allowed comparison of Clovis dates with dates of other archaeosites throughout the Americas, and of the opening of the ice-free corridor. Both lead to significant challenges to the Clovis First theory. The Monte Verde site of Southern Chile has been dated at 14.8k cal years BP. The Paisley Cave site in eastern Oregon yielded a 14C date of 12.4k years (14.5k cal years) BP, on a coprolite with human DNA and 14C dates of 11.3k-11k (13.2k-12.9k cal years) BP on horizons containing western stemmed points. Artifact horizons with non-Clovis lithic assemblages and pre-Clovis ages occur in eastern North America, although the maximum ages tend to be poorly constrained.

Geological findings on the timing of the ice-free corridor also challenge the notion that Clovis and pre-Clovis human occupation of the Americas was a result of migration through that route following the Last Glacial Maximum. Pre-LGM closing of the corridor may approach 30k cal years BP and estimates of ice retreat from the corridor are in the range of 12 to 13k cal years BP. Viability of the corridor as a human migration route has been estimated at 11.5k cal years BP, later than the ages of the Clovis and pre-Clovis sites. Dated Clovis archaeosites suggest a south-to-north spread of the Clovis culture.

Pre-Last Glacial Maximum migration into the interior has been proposed to explain pre-Clovis ages for archaeosites in the Americas, although pre-Clovis sites such as Meadowcroft Rock Shelter, Monte Verde, and Paisley Cave have not yielded confirmed pre-LGM ages.

Dené–Yeniseian language family proposal

A relationship between the Na-Dené languages of North America (such as Navajo and Apache), and the Yeniseian languages of Siberia was first proposed as early as 1923, and developed further by others. A detailed study was done by Edward Vajda and published in 2010. This theory received support from many linguists. Also archaeological and genetic studies gave it further support. 

The Arctic Small Tool tradition of Alaska and the Canadian Arctic may have originated in East Siberia about 5,000 years ago. This is connected with the ancient Paleo-Eskimo peoples of the Arctic, the culture that developed by 2500 BCE. 

The Arctic Small Tool tradition source may have been the Syalakh-Bel’kachi-Ymyakhtakh culture sequence of East Siberia, dated to 6,500 – 2,800 calBP.

The interior route is consistent with the spread of the Na-Dene language group and subhaplogroup X2a into the Americas after the earliest paleoamerican migration.

Nevertheless, some scholars suggest that the ancestors of western North Americans speaking Na-Dene languages made a coastal migration by boat.

Pacific coastal route

The Pacific 'coastal migration theory' proposes that people first reached the Americas via water travel, following coastlines from northeast Asia into the Americas, originally proposed in 1979 by Knute Fladmark as an alternative to the ice-free corridor hypothesis.

This model would help to explain the rapid spread to coastal sites extremely distant from the Bering Strait region, including sites such as Monte Verde in southern Chile and Taima-Taima in western Venezuela. The "marine migration hypothesis" is a variant of coastal migration which postulates the use of boats. The proposed use of boats adds a measure of flexibility to the chronology of coastal migration, because a continuous ice-free coast (16k-15k cal years BP) would no longer be required as migrants would have settled in coastal refugia during deglaciation of the coast. A coastal east Asian source population is integral to the marine migration hypothesis.

A 2007 article in the Journal of Island and Coastal Archaeology proposed a "kelp highway hypothesis", a variant of coastal migration based on the exploitation of kelp forests along much of the Pacific Rim from Japan to Beringia, the Pacific Northwest, and California, and as far as the Andean Coast of South America. Once the coastlines of Alaska and British Columbia had deglaciated about 16,000 years ago, these kelp forest (along with estuarine, mangrove, and coral reef) habitats would have provided an ecologically homogenous migration corridor, entirely at sea level, and essentially unobstructed. A 2016 DNA analysis of plants and animals suggest a coastal route was feasible.

Mitochondrial subhaplogroup D4h3a, a rare subclade of D4h3 occurring along the west coast of the Americas, has been identified as a clade associated with coastal migration. This haplogroup was found in a skeleton referred to as Anzick-1, found in Montana in close association with several Clovis artifacts, dated 12,500 years ago.

Problems with evaluating coastal migration models

The coastal migration models provide a different perspective on migration to the New World, but they are not without their own problems. One such problem is that global sea levels have risen over 120 metres (390 ft) since the end of the last glacial period, and this has submerged the ancient coastlines that maritime people would have followed into the Americas. Finding sites associated with early coastal migrations is extremely difficult—and systematic excavation of any sites found in deeper waters is challenging and expensive. Strategies for finding earliest migration sites include identifying potential sites on submerged paleoshorelines, seeking sites in areas uplifted either by tectonics or isostatic rebound, and looking for riverine sites in areas that may have attracted coastal migrants. On the other hand, there is evidence of marine technologies found in the hills of the Channel Islands of California, circa 10,000 BCE. If there was an early pre-Clovis coastal migration, there is always the possibility of a "failed colonization". Another problem that arises is the lack of hard evidence found for a "long chronology" theory. No sites have yet produced a consistent chronology older than about 12,500 radiocarbon years (~14,500 calendar years), but research has been limited in South America related to the possibility of early coastal migrations.

Woodland period

From Wikipedia, the free encyclopedia
 
In the classification of archaeological cultures of North America, the Woodland period of North American pre-Columbian cultures spanned a period from roughly 1000 BCE to European contact in the eastern part of North America, with some archaeologists distinguishing the Mississippian period, from 1000 CE to European contact as a separate period. The term "Woodland Period" was introduced in the 1930s as a generic term for prehistoric sites falling between the Archaic hunter-gatherers and the agriculturalist Mississippian cultures. The Eastern Woodlands cultural region covers what is now eastern Canada south of the Subarctic region, the Eastern United States, along to the Gulf of Mexico.

This period is variously considered a developmental stage, a time period, a suite of technological adaptations or "traits", and a "family tree" of cultures related to earlier Archaic cultures. It can be characterized as a chronological and cultural manifestation without any massive changes in a short time but instead having a continuous development in stone and bone tools, leather crafting, textile manufacture, cultivation, and shelter construction. Many Woodland peoples used spears and atlatls until the end of the period, when they were replaced by bows and arrows; however, Southeastern Woodland peoples also used blowguns.

The most cited technological distinction of this period was the widespread use of pottery (although pottery manufacture had arisen during the Archaic period in some places), and the diversification of pottery forms, decorations, and manufacturing practices. The increasing use of horticulture and the development of the Eastern Agricultural Complex, consisting of weedy seed plants as well as gourd cultivation, also meant that groups became less mobile over time and, in some times and places, people lived in permanently occupied villages and cities. Intensive agriculture characterizes the Mississippian period from c. 1000–1400 CE and may have continued up to European contact, around 500 years ago.

Early Woodland period (1000–200 BCE)

The Early Woodland period continued many trends begun during the Late and Terminal Archaic periods, including extensive mound-building, regional distinctive burial complexes, the trade of exotic goods across a large area of North America as part of interaction spheres, the reliance on both wild and domesticated plant foods, and a mobile subsistence strategy in which small groups took advantage of seasonally available resources such as nuts, fish, shellfish, and wild plants. Pottery, which had been manufactured during the Archaic period in limited amounts, was now widespread across the Eastern Interior, the Southeast, and the Northeast. The Far Northeast, the Sub-Arctic, and the Northwest/Plains regions widely adopted pottery somewhat later, about 200 BCE.

Interaction

The Adena culture built conical mounds in which single- or multiple-event burials, often cremated, were interred along with rich grave goods including copper bracelets, beads, and gorgets, art objects made from mica, novaculite, hematite, banded slate, and other kinds of stone, shell beads and cups, and leaf-shaped "cache blades". This culture is believed to have been core to the Meadowood Interaction Sphere, in which cultures in the Great Lakes region, the St. Lawrence region, the Far Northeast, and the Atlantic region interacted. The large area of interaction is indicated by the presence of Adena-style mounds, the presence of exotic goods from other parts of the interaction spheres, and the participation in the "Early Woodland Burial Complex" defined by William Ritchie 

Pottery

Pottery was widely manufactured and sometimes traded, particularly in the Eastern Interior region. Clay for pottery was typically tempered (mixed with non-clay additives) with grit (crushed rock) or limestone. Pots were usually made in a conoidal or conical jars with rounded shoulders, slightly constricted necks, and flaring rims. Pottery was most often decorated with a variety of linear or paddle stamps that created "dentate" (tooth-like) impressions, wavy line impressions, checked surfaces, or fabric-impressed surfaces, but some pots were incised with geometric patterns or, more rarely, with pictorial imagery such as faces. Pots were coiled and paddled entirely by hand without the use of fast rotation such as a pottery wheel. Some were slipped or brushed with red ochre. 

Pottery, agriculture, and permanent settlements have often been thought of the three defining characteristics of the Woodland period. However, it has become evident that, in some areas of North America, prehistoric cultural groups with a clearly Archaic cultural assemblage were making pottery without any evidence of the cultivation of domesticated crops. In fact, it appears that hunting and gathering continued as the basic subsistence economy and that subsistence horticulture/agriculture did not occur in much of the Southeast for a couple of thousand years after the introduction of pottery, and in parts of the Northeast, horticulture was never practiced. This research indicated that a fiber-tempered horizon of ceramics greatly predates 1000 BCE, first appearing about 2500 BCE in parts of Florida with the Orange culture and in Georgia with the Stallings culture. Nevertheless, these early sites were typical Archaic settlements, differing only in the use of basic ceramic technology. As such, researchers are now redefining the period to begin with not only pottery, but the appearance of permanent settlements, elaborate burial practices, intensive collection and/or horticulture of starchy seed plants (see Eastern Agricultural Complex), differentiation in social organization, and specialized activities, among other factors. Most of these are evident in the Southeastern Woodlands by 1000 BCE. 

In some areas, like South Carolina and coastal Georgia, Deptford culture pottery manufacture ceased after c. 700 CE.

Subsistence strategies

In coastal regions, many settlements were near the coast, often near salt marshes, which were habitats rich in food resources. People tended to settle along rivers and lakes in both coastal and interior regions for maximum access to food resources. Nuts were processed in large amounts, including hickory and acorns, and many wild berries, including palm berries, blueberries, raspberries, and strawberries, were eaten, as well as wild grapes and persimmon. Most groups relied heavily on white-tailed deer, but a variety of other small and large mammals were hunted also, including beaver, raccoon, and bear. Shellfish formed an important part of the diet, attested to by numerous shell middens along the coast and interior rivers.

Coastal peoples practiced seasonal mobility, moving to the coast during the summer to take advantage of numerous marine resources such as sea mammals and shellfish, then moved to interior locations during the winter where access to deer, bear, and anadromous fish such as salmon could see them through the winter. Seasonal foraging also characterized the strategies of many interior populations, with groups moving strategically among dense resource areas.

Recently evidence has accumulated of a greater reliance of woodland peoples on cultivation in this period, at least in some localities, than has historically been recognized. This is especially true for the middle woodland period and perhaps beyond. C. Margaret Scarry states "in the Woodland periods, people diversified their use of plant foods ... [they] increased their consumption of starchy foods. They did so, however, by cultivating starchy seeds rather than by gathering more acorns."  Smith and Yarnell refer to an "indigenous crop complex" as early as 3800 B.P. in parts of the region.

Middle Woodland period (200 BCE – 500 CE)

Hopewell Interaction Area and local expressions of the Hopewell tradition

The beginning of the Middle Woodland saw a shift of settlement to the Interior. As the Woodland period progressed, local and inter-regional trade of exotic materials greatly increased to the point where a trade network covered most of the Eastern Woodlands. Throughout the Southeast and north of the Ohio River, burial mounds of important people were very elaborate and contained a variety of mortuary gifts, many of which were not local. Among the traded materials were copper from the Lake Superior deposits; silver from Lake Superior and especially Ontario; galena from Missouri and Illinois; mica from the southern Appalachians; chert from various places including Ohio, Indiana, and Illinois; pipestone from Ohio and Illinois; alligator teeth from the lower Mississippi Valley eastward to Florida; marine shells, especially whelks, from the south Atlantic and Gulf coasts; Knife River chalcedony from North Dakota; and obsidian from Yellowstone in Wyoming. The most archaeologically certifiable sites of burial during this time were in Illinois and Ohio. These have come to be known as the Hopewell tradition. Due to the similarity of earthworks and burial goods, researchers assume a common body of religious practice and cultural interaction existed throughout the entire region (referred to as the "Hopewellian Interaction Sphere"). Such similarities could also be the result of reciprocal trade, obligations, or both between local clans that controlled specific territories. Access to food or resources outside a clan's territory would be made possible through formal agreements with neighbors. Clan heads would then be buried along with goods received from their trading partners to symbolize the relationships they had established. Under this scenario, permanent settlements would be likely to develop, leading to increased agricultural production and a population increase. 

Ceramics during this time were thinner and better quality than earlier times. Examples also show pottery also was more decorated than Early Woodland. One style was the Trempealeau phase which could have been seen by the Hopewell in Indiana. This type included a round body, and lines of decoration with cross-etching on rim. The Havana style found in Illinois had a decorated neck. One of the major tools unique to this era was Snyders Points. These were quite large and corner-notched. They were made by soft-hammering percussion, and finished by pressure flaking.

Although many of the Middle Woodland cultures are called "Hopewellian", and groups shared ceremonial practices, archeologists have identified the development of distinctly separate cultures during the Middle Woodland period. Examples include the Armstrong culture, Copena culture, Crab Orchard culture, Fourche Maline culture, the Goodall Focus, the Havana Hopewell culture, the Kansas City Hopewell, the Marksville culture, and the Swift Creek culture.

The Center for American Archeology specializes in Middle Woodland culture.

Late Woodland period (500–1000 CE)

The late Woodland period was a time of apparent population dispersal, although populations do not appear to have decreased. In most areas construction of burial mounds decreased drastically, as well as long-distance trade in exotic materials. At the same time, bow and arrow technology gradually overtook the use of the spear and atlatl, and agricultural production of the "Three Sisters" (maize, beans, and squash) was introduced. While full scale intensive agriculture did not begin until the following Mississippian period, the beginning of serious cultivation greatly supplemented the gathering of plants.

Late Woodland settlements became more numerous, but the size of each one (with exceptions) was smaller than their middle Woodland counterparts. The reasons for this are unknown, but it has been theorized that populations increased so much that trade alone could no longer support the communities and some clans resorted to raiding others for resources. Alternatively, the efficiency of bows and arrows in hunting may have decimated the large game animals, forcing the tribes to break apart into smaller clans to better use local resources, thus limiting the trade potential of each group. A third possibility is a colder climate may have affected food yields, possibly affected by Northern Hemisphere extreme weather events of 535–536, also limiting trade possibilities. Lastly, it may be that agricultural technology became sophisticated enough that crop variation between clans lessened, thereby decreasing the need for trade.

As communities became more isolated, they began to develop in their own unique ways, giving rise to small-scale cultures that were distinctive to their regional areas. Examples include the Baytown, Troyville and Coles Creek cultures of Louisiana, the Alachua and Weeden Island cultures of Florida, and the Plum Bayou culture of Arkansas and Missouri.

Although the 1000 CE ending of the Late Woodland period is traditional, in practice many regions of the Eastern Woodlands adopted the full Mississippian culture much later than that. Some groups in the north and northeast of the current United States, such as the Iroquois, retained a way of life that was technologically identical to the Late Woodland until the arrival of Europeans. Furthermore, despite the widespread adoption of the bow and arrow during this time, the peoples of a few areas appear never to have made the change. During Hernando de Soto's travels through the Southeastern Woodlands around 1543, the groups at the mouth of the Mississippi river still preferentially used the spear.

Algorithmic information theory

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Algorithmic_information_theory ...