The spread of crop agriculture

Polynesian–American contact · c. 1200–1400 CE
Contact around 1200 CE; island estimates differ. Rapanui–Native American admixture estimated 1250–1430 CE. Genetic evidence supports pre-European contact. Polynesian voyages to the Americas and return are plausible, but the direction, number of voyages and landing places remain unresolved. Both endpoints and the dashed two-way path are illustrative regions. The 1200 CE display cue is approximate; the studies estimate admixture, not an observed voyage. This overlay introduces no farming coverage.
Ioannidis et al. 2020, Native American gene flow into Polynesia; Moreno-Mayar et al. 2024, Ancient Rapanui genomes and American contact

1. Gronenborn, Horejs, Hoffmann, Börner and Ober 2026.2, Expansion of farming in western Eurasia · CC BY 4.0 — Primary source for the user-supplied western reference. The authors describe a condensed and simplified map; dates are approximate calibrated BCE. The new polygons are schematic adaptations, not the original georeferenced data or measured boundaries.
2. Bishop et al. 2022, Scotland's first farmers: new insights into early farming practices in north-west Europe — Archaeobotanical cereal evidence from early fourth-millennium Scotland, including Dubton Farm phase 1 at c. 3940–3659 cal BCE. A 3800 BCE regional display label is rounded; broad Scottish coverage is approximate.
3. Dulias et al. 2022, Ancient DNA at the edge of the world — Archaeological background identifies a flourishing farming economy in Neolithic Orkney, 3800–2500 BCE. The 3700 BCE island label summarizes early crop farming, not a directly dated frontier.
4. Hjelle et al. 2017, Prehistoric agriculture in western Norway: botanical evidence — Separates early landscape disturbance from cultivation. Cereal macroremains and arable weeds establish crop farming by the Late Neolithic, 2300–1800 BCE; the conservative 2300 BCE label does not date earlier pastoral activity as cultivation.
5. Malleson 2026, Cereals, UCLA Encyclopedia of Egyptology — Specialist review of Egyptian crop evidence places earliest Fayum cereals near 5000 BCE with broad dating uncertainty. The Nile/floodplain extents and a later upper-valley 4000 BCE label are regional syntheses, not a claim that Egypt was uniformly cultivated.
6. Eastern farming map: regional chronology and linked evidence — Reuses the reviewed regional dates, with secondary-source dates retained as approximate. Earlier pastoralism, Ubaid contact, and traded-grain-only zones are omitted from this crop map.
7. Motuzaite Matuzeviciute et al. 2022: Central Tian Shan farming — Chap II occupation modeled to 2474–2162 cal BCE; cereal chaff supports local cultivation and processing.
8. Mutin et al. 2025: Mehrgarh chronology — Cemetery start 5223–4914 BCE; this does not exclude earlier occupation elsewhere at the site.
9. Riehl, Zeidi and Conard 2013: cultivation at Chogha Golan — Long-term plant management precedes morphologically domesticated emmer. The early map date includes cultivation, not only fully domesticated cereals.
10. Hili 8: early oasis agriculture — Excavation report dates the earliest building to about 3000 BCE and reports cereals. Coverage is restricted to the Hajar foothill oases.
11. Agricultural terraces in Yemen — Cultivation in the highlands is represented conservatively around 2500 BCE; this does not extend earlier inland cattle evidence to the coast.
12. Spengler Lab: Kazakhstan archaeobotanical fieldwork — Late Bronze Age cultivation and processing replace the earlier Begash funerary-grain date as the basis for colored farming coverage.
13. Gao et al. 2021: Qugong crop assemblage — Crop assemblage around 3400 cal BP, approximately 1450 BCE; a 2024 site model instead places the early phase around 1400–1300 BCE.
14. Mission Archéologie Caucase: Aknashen-Khaturnakh excavations — The excavation team reports wheat and barley farming in the Ararat plain during occupation approximately 6000–5400 BCE. This supports a local Araxes/Ararat cultivation envelope, not farming across the entire Armenian highlands.
15. Archeoseismicity and environmental crises at the Sialk Mounds, Central Iranian Plateau, since the Early Neolithic — Study of the excavated Sialk mounds on the desert-edge Kashan plain. The retained 5900 BCE display date follows the existing chronology. The broader regional envelope is schematic, not a surveyed frontier; the Kavir desert remains excluded.
16. The Neolithisation of Fars: charred plant remains from Tol-e Sangi — Primary archaeobotanical report on Tol-e Sangi, approximately 7050–6650 BCE, and comparison with Rahmatabad. The inherited 7300 BCE regional horizon remains approximate. The broader Fars envelope is a schematic regional summary, not a claim that every valley was cultivated at that date.
17. Didier and Mutin: The Kech Makran Region in Protohistoric Times — Excavation synthesis for Miri Qalat and Shahi-Tump with archaeobotanical evidence, including wheat and barley. The earliest sequence spans the late fifth/fourth millennia BCE. The inherited 4500 BCE display label is qualified; the crop envelope is confined to the Kech/Dasht valley system rather than an uninterrupted cultivated Makran coast.
18. Zhao et al. 2013: Agriculture and the oasis landscape at Xintala — Pollen and charred seeds document wheat cultivation and farmland expansion approximately 3900–3600 cal BP, about 1950–1650 BCE. The overview uses a conservative by-1500 BCE horizon for this locally cultivated Yanqi/Bosten oasis; it is not an exact introduction date or evidence for farming throughout the Tarim Basin.
19. Francfort and Lecomte 2002: Irrigation and society in Central Asia — The field-based account describes mapped irrigation canals and cereal agriculture at Djoumboulak Koum in the old Keriya delta. Later chronology summarizes the settlement around 400–0 BCE; the map uses by-1 CE as a conservative documented-by horizon, not the first arrival of crops or a new regional origin.
20. Xia and Zhang 2016: AMS dating and historical geography of the Yuansha delta — Primary delta survey locates Yuansha/Djoumboulak Koum at approximately 38°52′N, 81°35′E. The map shows an enlarged palaeochannel-region cue around that location, not the excavated town or field boundaries.
21. Smith 2001 — Documenting plant domestication — Guilá Naquitz domesticated squash around 10,000 calibrated years BP; maize macrofossils about 6,300 cal BP. Mexican crop histories differ by species. Broad regional connections on this map are cartographic estimates, not newly dated boundaries.
22. Ranere et al. 2009 — Early maize and squash in the Central Balsas — Xihuatoxtla crop evidence in contexts around 8,700 cal BP, approximately 6750 BCE. The small patch denotes local early cultivation, not all Mesoamerica.
23. Merrill et al. 2009 — The diffusion of maize to the southwestern United States — Maize is established in the US Southwest by 2100 cal BCE. The northern Mexican connector and later northern extent are schematic; adoption was uneven and crop presence did not immediately imply staple dependence.
24. Smith and Yarnell 2009 — An indigenous crop complex in eastern North America — Phillips Spring squash: 5025 cal BP (about 3100 BCE); Hayes sunflower: 4840 cal BP (about 2900 BCE); Riverton crop complex: 3800 cal BP (1850 BCE). These are independent indigenous crop histories. Regional coverage remains schematic.
25. Katzenberg et al. 1995 — Maize horticulture and paleodiet in southern Ontario — Isotopic evidence shows increasing maize contribution between 650 and 1250 CE. The 800 and 1000 CE northern zones summarize regional adoption within that broad interval, not exact first-arrival boundaries.
26. Kennett et al. 2020 — Early isotopic evidence for maize as a staple grain in the Americas — Belize dietary transition at 4700–4000 cal BP, approximately 2750–2050 BCE. The rounded 2500 BCE zone illustrates increasing maize reliance; some crops and maize presence were earlier.
27. Dickau, Ranere and Cooke 2007 — Preceramic dispersals of maize and root crops in Panama — Central Panama maize at 7800–7000 cal BP; maize and root crops in western Panama at 7400–5600 cal BP. A small early patch is shown around 5800 BCE; routes between sampled areas are inferred.
28. Grobman et al. 2012 — Preceramic maize from Paredones and Huaca Prieta, Peru — Northern Peruvian maize macrofossils directly dated to 6775–6504 cal BP, approximately 4825–4554 BCE. Maize joined older local horticultural systems; this is not the first cultivation of every crop in Peru.
29. Rumold and Aldenderfer 2016 — Potato evidence at Jiskairumoko — Cultivated or domesticated potato starch occurs in Late Archaic–Early Formative contexts. The local 3000 BCE patch is rounded within the regional Terminal Archaic chronology; it is not a precise domestication year.
30. Bruno 2023 — Archaeobotanical insights into kañawa domestication — The southern Titicaca record documents established quinoa and tuber farming before later kañawa cultivation. The broad 1500 BCE Andean band is schematic regional coverage around an established Formative farming horizon.
31. Lombardo et al. 2020 — Early Holocene crop cultivation in southwest Amazonia — Managed forest islands in Llanos de Moxos contain Manihot around 10,350 cal BP and squash around 10,250 cal BP. The 8400 BCE patch is deliberately local; it does not paint the whole Amazon as early farmland.
32. Watling et al. 2018 — Southwestern Amazonia as an early food-production centre — Teotônio manioc and squash cultivation is associated with contexts around 6500–5500 cal BP, roughly 4550–3550 BCE. Later river-corridor coverage shown here is inferred and does not date an entire forest boundary.
33. Pagán-Jiménez et al. 2015 — Early dispersals of food plants into the southern Caribbean — Southern Caribbean and northeastern South American cultigen use reaches at least 7790 cal BP. This early use is distinguished from the later expansion and intensification of island horticulture.
34. Mickleburgh and Pagán-Jiménez 2012 — Food plants in pre-Columbian Caribbean dental calculus — Plant management predates the Ceramic Age; horticulture intensified from roughly 400 BCE onward. The 400 BCE zone is a later regional horticultural horizon, not the first appearance of crops on every island.
35. Planella et al. 2019 — Quinoa in pre-Hispanic central Chile — Late Archaic central Chile includes quinoa remains; the Las Morrenas record is dated around 3250–2980 cal BP (1300–1030 BCE). A narrow 1200 BCE zone summarizes this local crop history.
36. Campbell et al. 2020 — Diet in Southern Chile, 36°–42°S — Regional isotopic synthesis discusses variable crop use at the southern limit of precontact agriculture. The 1000 CE patch is an approximate later farming extent, not a uniform first-adoption date.
37. Lu et al. 2009, Earliest domestication of common millet — Cishan phytolith/storage evidence spans 10,300–8,700 cal BP. A conservative 6500 BCE display label is used for a crop-producing North China region; this is not a single precise domestication date.
38. Zheng et al. 2016, Rice domestication and reduced shattering — Huxi rice cultivation/selection at 9000–8400 BP; later Lower Yangtze sites document a prolonged domestication process. Rounded map dates mark cultivation, not fully domesticated rice throughout a modern region.
39. Fuller 2011, Pathways to Asian civilizations — Specialist synthesis of distinct Asian rice histories and dispersal. Regional polygons and connecting dates remain schematic; local South Asian cultivation is not a direct extension of Chinese rice farming.
40. Bellwood 2011, The checkered prehistory of rice movement southwards — Mainland crop dispersals after about 2500/2000 BCE and Taiwan rice/millet around 2800 BCE. Island Southeast Asian rice histories are patchy; the diagram does not assume early rice was a staple everywhere.
41. Deng et al. 2022, Rice and millet cultivated in Ha Long Bay — Rice and millet phytolith evidence in northeastern Vietnam around 4000 cal BP. Wider mainland coverage and routes are approximate.
42. Choy et al. 2021, Direct isotopic evidence for millet consumption in Korea — Specialist background places early Korean domestic millets around 3500 BCE; the study directly examines later Middle Mumun diet. The earlier regional extent remains schematic.
43. 2020 Bayesian analysis of direct dates for the spread of rice to Japan — Introduction of cereal farming modeled at 1190–820 cal BCE; northern Tohoku expansion falls broadly 450–200 BCE. Map labels 1000 and 300 BCE are rounded regional summaries.
44. Fuller et al. 2004, Early plant domestications in southern India — Flotation samples from twelve Karnataka and Andhra Pradesh sites support third-millennium BCE cultivation of indigenous millets and pulses. The 2500 BCE display envelope follows the southern semiarid interior; later western cereals and African crops were secondary additions. Neither the date nor the outline establishes contemporaneous cultivation throughout peninsular India.
45. Fuller 2011, Finding plant domestication in the Indian subcontinent — Distinguishes southern indigenous-crop systems from the northern Deccan Chalcolithic, with increasing sedentary farming along the savanna corridor after about 2200–2000 BCE. The 2000 BCE regional display horizon is approximate; it is not a directly dated frontier or a claim that every tributary basin adopted the same crops together.
46. Kingwell-Banham et al. 2018, Archaeobotanical investigations into Golbai Sasan and Gopalpur — Directly dated Golbai Sasan rice spans 3450–3350 cal BP (approximately 1500–1400 BCE); rice, pulse and millet evidence establishes coastal-lowland agriculture. A conservative 1400 BCE display horizon replaces older typological claims of much earlier farming. Adjacent upland archaeology does not establish the same crop economy throughout the Eastern Ghats.
47. Kingwell-Banham 2019, Dry, rainfed or irrigated? Rice agriculture in South India — Comparative archaeobotany places major rice adoption in southern India in the later first millennium BCE. A 500 BCE coastal/lower-river display horizon is an inferred regional summary, not direct dating of every delta. East-coast dispersal is one possible route; the paper stresses patchy evidence and does not establish early irrigation everywhere.
48. Amano et al. 2021, Archaeological and historical plant introductions in the Philippines — Early crop evidence is sparse and staple rice farming cannot be inferred from Neolithic pottery or settlement. The 1500 BCE island-region label is an uncertain cultivation display horizon, not a universal staple-rice arrival.
49. Denham et al. 2003, Origins of agriculture at Kuk Swamp — Mounding and banana cultivation at 6950–6440 cal BP support the rounded 4700 BCE label. Possible earlier cultivation at 10,220–9910 cal BP is not used as established agriculture.
50. 2024 sediment biomarkers for taro horticulture on Efate — Unequivocal taro biomarker signal around 2800 BP supports a rounded 850 BCE local horticulture date; it does not date every Oceanic crop.
51. Burley et al. 2020, Pit cultivation at Nukuleka, Tonga — Pit cultivation in a first Lapita settlement context around 2850 cal BP. This supports local cultivation, rather than a date for an entire Pacific crop package.
52. Wilmshurst et al. 2011, High-precision East Polynesian settlement chronology — Society Islands settlement approximately CE 1025–1120 and later expansion approximately CE 1190–1290 provide earliest opportunities for introduced cultivation. Eastern island cultivation labels are inferred horizons, not directly dated seeds.
53. Te Ara, Plants introduced from Polynesia — New Zealand government encyclopedia: introduced cultigens accompanied Polynesian settlers around CE 1250–1300, with Society or Cook Islands connections discussed for kumara. The Eastern Polynesia connection is inferred, not a direct Tonga-to-New Zealand voyage. Only the warmer northern cultivation region is shaded.
54. Winchell et al. 2017, Sorghum domestication in eastern Sudan — Fourth-millennium BCE KG23 pottery contains wild and domestic-type sorghum spikelet impressions. The 3500 BCE label marks an ongoing local cultivation/domestication process.
55. Manning et al. 2011, 4500-year-old domestic pearl millet from Mali — Lower Tilemsi domesticated pearl millet in the middle third millennium BCE. The 2300 BCE map label and wider western Sahel outline are deliberately rounded.
56. Beldados et al. 2018, Early African crop evidence and exchange — Specialist review of pearl millet and African crop dispersals; broader Sahel and savanna extents are approximate adoption windows, not synchronized agricultural frontiers.
57. 2022, Iron Age plant subsistence in the Inner Congo Basin — Iyonda pearl millet and cowpea around 400 BCE–CE 50; southern Cameroon crop finds around 400–200 BCE, and Nok/Benin crop finds around 800–400 BCE. Small rainforest crop quantities do not imply blanket clearance.
58. Ruiz-Giralt et al. 2023, On the verge of domestication: early C4 plant use in the Horn — Mezber agriculture begins around 1600 BCE; introduced barley and locally used millets/tubers coexisted. The exact early history of indigenous cereal domestication is unresolved.
59. Becher et al. 2024, Early farming food processing at Lydenburg — Farming communities in eastern southern Africa from approximately the third century CE. The map includes crop-farming areas only; earlier non-crop food production does not date these zones.
60. Crowther et al. 2016, Ancient crops and westward Austronesian expansion — Asian crops are directly attested in Comoros/Madagascar sites during the later first and early second millennium CE. A CE 1000 island label is conservative; earlier agriculture may remain archaeologically invisible.
61. Deng et al. 2020, Validating earliest rice farming in the Indonesian Archipelago — Minanga Sipakko has domestic-type rice leaf/husk phytoliths and on-site processing in a horizon dated 3562–3400 cal BP. Rounded 1500 BCE is supported for local rice farming; the polygon is not a synchronized date for every part of Sulawesi.
62. The development of sawah cultivation in ancient Java, epigraphic study — Historical inscriptions document established irrigated rice farming in eighth-century Java. CE 800 is a conservative documented-by horizon, not the first introduction of agriculture to Java.
63. Magnavita et al., Gajiganna crop sequence in the Lake Chad Basin — Research-project sequence reports pearl millet from about 1200 cal BCE. The earlier 1800–1500 BCE phase lacks evidence of domestic plants and is not used as a crop-farming date. The southern Sahel connecting extent is schematic.
64. Kingwell-Banham 2015, Early rice agriculture in South Asia, UCL thesis — Archaeobotanical synthesis places rice farming in Sri Lanka by about 500 BCE. Earlier Anuradhapura phase-context claims of 900–600 BCE exist; the map adopts a conservative documented-by farming horizon.
65. Barton et al. 2009, Agricultural origins in northern China — Dadiwan had low-intensity millet use/production at 7900–7200 cal BP, followed by intensive cultivation of broomcorn and foxtail millet by 5900 cal BP. The regional 4000 BCE map label represents the latter established crop-farming phase; it is not the earliest local plant use.
66. Zhou et al. 2016, Rapid agricultural transformation in the prehistoric Hexi Corridor — Flotation and AMS dating at eight sites establish millet agriculture by about 2300 BCE, followed by wheat cultivation around 2000 BCE. The colored corridor is a schematic farming extent, not a continuous surveyed belt. It is not dated from imported funerary grain.
67. Hausleiter and Eichmann, Tayma I: Archaeological Exploration, Palaeoenvironment, Cultural Contacts — Project chronology, table 1: local grapevine and fig cultivation around 4600 BCE. This is an oasis horticulture horizon, not a date for all cereals or northwestern Arabia. Earlier Cerealia-type pollen has a different evidential status.
68. Rohmer et al., Tall al-Salimiyyah test excavation, Dadan Archaeological Project (PSAS 51) — Excavation and archaeobotany identify local date-palm cultivation in the 12th–11th centuries BCE. The rounded 1100 BCE cue is limited to the AlUla valley; it does not date a continuous Hijaz farming corridor.
69. Thanheiser, Introduction of Agriculture in Dakhleh: archaeobotanical project final report — The project places the introduction of an Egyptian agricultural economy around 2300 BCE, after earlier local pastoral lifeways. This local Old Kingdom horizon does not establish crop cultivation across the surrounding Western Desert.
70. Agut-Labordere, Collection, storage and distribution of cereals at Ayn Manawir, Kharga Oasis — Persian-period documents, 5th–4th centuries BCE, record the local wheat and barley economy. The 450 BCE documented-by cue is confined to the southern Kharga irrigated basin; it is not a proposed first arrival of farming.
71. Le Moyne et al. 2023, Dietary shifts between the Neolithic and Kerma periods at Kadruka — The study relates increased hulled-barley and emmer production on the alluvial plain to the start of Kerma Moyen, around 2050 BCE. Earlier Neolithic cereal finds have disputed dietary significance and are not used to paint a broad early farming zone.
72. Levkovskaya and Filatenko 1992, Palaeobotanical and palynological studies in South Arabia — Raybun plant assemblages span approximately the 8th–6th centuries BCE through the first centuries CE and document cultivated flora in the inland oasis. A rounded 700 BCE local cultivation cue does not extend to all Hadramawt, Mahra or the coastal desert.
73. 2020, Food plants in pollen records from ancient Southern Arabia: Sumhuram, Southern Oman — The study distinguishes plant use at the ancient trading port from local cultivation, and discusses Ibn Battuta's 14th-century account of Zafar gardens and cultivated cereals. The by-c.1330-CE Salalah cue rounds his disputed travel chronology to a historical horizon; it is not a first-arrival date or an inference from imported rice.
74. Hildebrand and Schilling 2016, Storage amidst early agriculture along the Nile: perspectives from Sai Island, Sudan — Sai site 8-B-52A documents local cereal production, processing and sustained storage during the Pre-Kerma period, around 2700 BCE. Earlier cereal finds in graves alone do not establish regular farming.
75. Le Moyne et al. 2023, Dietary shifts between the Neolithic and Kerma periods at Kadruka — The study associates intensified barley and emmer production on the alluvial plain with Kerma Moyen around 2050 BCE. The broader river reach is approximate, while the existing local Kadruka/Kerma record remains separate.
76. Fuller 2015, The economic basis of the Qustul splinter state: cash crops, subsistence shifts and labour demands — Pages 37–40 discuss winter-cereal farming and Meroe sorghum cultivation in the last centuries BCE. The author also reports directly dated Abu Geili sorghum at 100–350 CE and Jebel Tomat evidence at 100–400 CE.
77. Gorbanenko and Merkulov 2018, Grain farming of the Middle Don population at the Scythian time — Flotation and crop/weed impressions establish cereal farming in the Middle Don forest-steppe during the Scythian period. The 500 BCE regional cue is rounded; earlier Lower Don pastoral or plant-use evidence is not treated as crop farming.
78. Salova, Vyazov and Benes 2024, When Barley and Wheat Meet Millet — Analysis of plant macroremains from 321 East European forest/forest-steppe sites. Millet occurs in the 850–250 BCE assemblages, including the Oka; later assemblages document diverse cereal production in the Middle Volga. Rounded regional dates do not date every intervening clearing.
79. Orlova et al. 2025, Archaeobotanical and isotope studies of early cultivation in the Kama basin — Plant remains and cereal isotopes establish emmer and barley cultivation in the mid-Kama during the Late Ananyino period, by the fourth century BCE. The 400 BCE map cue is rounded; it does not extend the farming frontier through the northern taiga or across the Urals.
80. Alsleben 2012, The plant economy of northern medieval Russia — Primary archaeobotanical study of Novgorod and rural northern Russian sites documents cereal cultivation and processing in the medieval agricultural hinterland. The by-1000 CE cue summarizes the Ilmen/Volkhov farming landscape, not a first-arrival date or the full territory ruled from Novgorod.
81. Makarov et al. 2023, Archaeology of the Suzdal Country: settlement and cultural landscape — Excavation, flotation and pollen studies record cultivated cereals and processing debris in the Suzdal countryside. A broad open agricultural landscape developed during the twelfth century. The by-1200 CE regional extension represents established medieval farming, not its earliest local appearance.
82. Ryabogina and Ivanov 2011, Ancient agriculture in Western Siberia: palaeobotanical data — Analysis of known and new botanical evidence distinguishes local cultivated cereals from ambiguous pollen, tools and gathering. The upper Ob regional cue is conservatively placed in the early medieval period; earlier pastoral settlement is not used to color the West Siberian plain.
83. Adamov, Korona and Ryabogina 2016, Palaeoethnobotanical and archaeological evidence of plough agriculture in the Tobolsk Irtysh region — Primary report, pages 15–19, on crop and agricultural evidence from twelfth–fourteenth-century settlements. The by-1300 CE footprint is restricted to the Tobolsk/Tobol–Irtysh farming setting; it does not imply prehistoric cultivation across the surrounding West Siberian wetlands.
84. Svyatko et al. 2013, Isotope analysis and the introduction of millet to the Minusinsk Basin — The isotope study finds substantial millet use from the Late Bronze Age, probably around 1500 BCE; charred millet/barley also occur in Early Iron Age Tagar contexts. The 800 BCE regional map cue uses that later directly attested cultivation setting, rather than assuming millet consumption maps exact fields.
85. Sergusheva et al. 2022, Evidence of millet and millet agriculture in the Russian Far East — Systematic archaeobotany and direct grain dates establish millet agriculture in southern Primorye and its spread to the Khanka plains during the third millennium BCE. The 2400 BCE overview horizon summarizes that regional expansion; older fourth-millennium estimates depend on associated charcoal rather than direct millet dates.
86. Brite et al. 2017, Kara-tepe: agropastoralism in a Central Eurasian oasis — The primary household excavation documents fourth/fifth-century CE crops and reviews the earlier Khorezm canal and plant record. Sixth/fifth-century BCE irrigation and earlier crop reports support a rounded by-500-BCE regional cue; the early crop identifications and dates are less secure than the later excavated assemblage.
87. Boston University Environmental Archaeology Laboratory: Khorezm Ancient Agriculture Project — The excavators describe Khorezm as an agricultural oasis from the seventh century BCE onward and explain the limited systematic archaeobotanical sampling of its early periods. This supports a regional irrigation history, not a precise first-crop date or exact ancient field boundary.
88. Mir-Makhamad et al. 2023, Food globalization in southern Central Asia: archaeobotany at Bukhara — Samples span the third to eleventh centuries CE; cotton is directly dated to the fourth century and the authors describe the irrigated cereal/cotton economy of the surrounding oasis. By-400-CE marks documented agriculture, not its introduction. City deposits include clean grain supplied from farms, and some food plants could be imported.
89. Kume et al. 2024, Cereal storage or processing in Late Bronze Age Fergana (World Neolithic Congress abstract, p. 708) — The excavators report storage/processing pits and a preliminary macroremain assemblage dominated by broomcorn and foxtail millet at Dalverzin. The map uses a rounded c.1000-BCE Late Bronze/Early Iron Age regional cue; this preliminary report does not supply an exact first-arrival date or establish the date of every Fergana field.
90. Jiang et al. 2013, Ancient plant use at Yuergou, Xinjiang — Yuergou is dated approximately 2300-2400 BP. Wheat, naked barley and broomcorn millet were probably cultivated, with chaff and local weeds supporting crop processing and cultivation. The by-300-BCE overview cue is rounded and later than this approximate context; it is not the beginning of farming throughout the Turpan Basin.
91. Abdurusul, Abulkasim and Roberts 2012, Niya field investigations (IDP News 39, pp. 2-5) — The Sino-British survey describes cultivated areas, irrigation canals and orchards in the ancient Niya delta. Its field account dates the flourishing grain/fruit/wine farmsteads to the first through third centuries CE. By-300-CE is a documented cultivation horizon; the enlarged local footprint does not fill the intervening Taklamakan.
92. Xuanzang, Buddhist Records of the Western World, Book XII: Khotan (Beal translation) — The seventh-century travel account distinguishes a small cultivated portion of Khotan from surrounding sand and gravel and describes abundant fruit production. The rounded by-650-CE cue represents the witnessed agricultural oasis, not its first settlement, initial crop introduction or cultivation of the surrounding desert.
93. Fuller et al. 2011, Across Asia
94. Gronenborn et al. 2021 supplied spread map — No external source URL has been verified for this retained reference.
95. Legacy estimate from memory; not source-verified — No external source URL has been verified for this retained reference.
96. Aceituno and Loaiza 2014, Early and Middle Holocene plant use and cultivation in the Middle Cauca River Basin — Regional microbotanical and stratigraphic evidence establishes early horticultural histories. The display uses a conservative later regional cue; the paper does not date every valley or map continuous fields.
97. Athens et al. 2016, Early Prehistoric Maize in Northern Highland Ecuador — Lake San Pablo maize pollen is reported by 4900 cal BP, with older phytolith indications. This supports valley farming, not cultivation on volcanic summits; regional interpolation begins later.
98. Becher et al. 2024, Multi-purpose pots at Lydenburg Heads
99. Beldados et al. 2018, Sorghum and pearl millet origins and dissemination
100. Billings et al. 2022, Agriculture in the Karakum: Togolok 1 archaeobotany — The primary assemblage is Togolok. Its introduction reviews earlier Jeitun agriculture and cites the excavations; it does not provide a new direct date for Jeitun.
101. Bruno 2014, Beyond Raised Fields: farming practices and agricultural change in the ancient Lake Titicaca Basin — Macrobotanical and archaeological datasets on the Taraco Peninsula span 1500 BCE–500 CE and document sustained quinoa / tuber farming with gradual diversification.
102. Camperio et al. 2024, Sedimentary biomarkers of human presence and taro cultivation in Remote Oceania
103. Çevik & Erdoğu 2020, Ulucak absolute chronology 6850–5460 cal BCE
104. Chepstow-Lusty 2011, Agro-pastoralism and social change in the Cuzco heartland of Peru — Marcacocha proxies record agro-pastoral change over 4200 years and highland maize / weeding practices about 2700 years ago. The later regional cue does not imply agriculture began everywhere at once.
105. Preliminary results of ceramic technology in early agropastoral La Cienega valley villages, northwestern Argentina (ca. 200 BC–AD 900) — The studied early agricultural / agropastoral settlements provide a conservative regional horizon for valley coverage. The archaeology does not establish simultaneous field creation throughout northwestern Argentina.
106. Clement et al. 2015, The domestication of Amazonia before European conquest
107. Denham et al. 2003, Origins of agriculture at Kuk Swamp
108. de Souza & Riris 2021, Delayed demographic transition following the adoption of cultivated plants in the eastern La Plata Basin and Atlantic coast
109. Dillehay et al. 2005, Preceramic irrigation canals in the Peruvian Andes — The Zana valley canal sequence establishes organized irrigation by about 5400 years ago, probably earlier. Its discussion supports more extensive Central Andean irrigation by about 4000 years ago; valley geometry remains authored.
110. Eerkens et al. 2024, Long-Term Camelid Husbandry and Agricultural Intensification in the Southern Nasca Region, Peru — Faunal isotopes and archaeological context at Upanca document changes through 3200–3000 BCE to 100–650 CE; comparisons include Palpa/Nasca horticultural settlements. A later regional cue represents established valley production rather than the earliest crop.
111. Falabella et al. 2020, Social differentiation in the pre-Hispanic horticultural societies of central Chile (200–1500 AD)
112. Fernandes et al. 2021, A genetic history of the pre-contact Caribbean — Used for its archaeological context of Ceramic Age intensified agriculture, not to turn ancestry proportions or genetic replacements into crop arrival dates.
113. Garvin Suero et al. 2024, Homeland Food Traditions in Tiwanaku colonies: cultivation in the Middle Horizon Locumba Valley, Peru — Archaeobotanical remains at Cerro San Antonio, Locumba, and comparisons with Moquegua/Tiwanaku support cultivation in southern Peruvian valley colonies during 600–1100 CE. Regional geometry remains illustrative.
114. Grobman et al. 2012, Preceramic maize from Paredones and Huaca Prieta, Peru
115. d’Alpoim Guedes et al. 2015, Wheat and barley on Tibetan Plateau margins
116. Haas et al. 2013, Evidence for maize in the Late Archaic (3000–1800 BC), Norte Chico, Peru — Multiple sampled sites, pollen, coprolites, residues and radiocarbon contexts support regional maize production and consumption in the third millennium BCE. Coverage is restricted to selected coastal valleys, with regional interpolation explicitly inferred.
117. Harris, Gosden & Charles 1996, Jeitun: Recent excavations at an early Neolithic site in southern Turkmenistan
118. Heckenberger et al. 2008, Pre-Columbian urbanism, anthropogenic landscapes, and the future of the Amazon
119. Ioannidis et al. 2020, Native American gene flow into Polynesia
120. Iriarte et al. 2012, Fire-free land use in pre-1492 Amazonian savannas
121. Iriarte et al. 2017, Out of Amazonia: Late-Holocene climate change and the Tupi–Guarani trans-continental expansion
122. Iriarte et al. 2020, The origins of Amazonian landscapes
123. Isern & Fort 2019, Archaeological models of farming spread into eastern and southeastern Africa — A regional spread analysis using Early Iron Age settlement/metallurgical proxies, mostly not directly dated crops. It supports a broad Great Lakes-to-southeastern sequence, not exact atlas corridor edges or every local arrival date.
124. Langlie and Capriles 2021, Agricultural mutualism among early camelid pastoralists of the Andean central Altiplano — Paleoethnobotany documents quinoa, kanawa and tuber cultivation among mobile Wankarani pastoralists of the Iroco region during 1500 BCE–500 CE. The area is not assigned a maize package or a uniform sedentary economy.
125. Lentfer & Green 2004, Phytoliths and banana cultivation at the Lapita Reber-Rakival site, Watom — The reported local sequence is approximately 400 cal BCE–650 cal CE. It supports regional horticultural practices, not the timing of the earlier network start or an exact outward voyage.
126. Lombardo et al. 2020, Early Holocene crop cultivation in Amazonia
127. Maezumi et al. 2018, The legacy of 4,500 years of polyculture agroforestry in the eastern Amazon
128. Mickleburgh & Pagán-Jiménez 2012, Food plants in pre-Columbian Caribbean dental calculus
129. Miller et al. 2021, Quinoa, potatoes, and llamas fueled emergent social complexity in the Lake Titicaca Basin of the Andes
130. Moreno-Mayar et al. 2024, Ancient Rapanui genomes and American contact
131. Neumann, Eichhorn & Wotzka 2022, Iron Age plant subsistence in the Inner Congo Basin
132. Pagán-Jiménez et al. 2015, Early dispersals of maize and other food plants into the Southern Caribbean and Northeastern South America
133. Ranere et al. 2009, Cultural and chronological context of early maize and squash in Central Balsas
134. Roa et al. 2018, Southern dispersal of cultigens: archaeobotanical and radiometric evidence from Isla Mocha and Cueva de los Catalanes, Chile — New archaeobotanical evidence and radiometric chronology support later pre-European cultigen use in south-central Chile. The regional display begins around 1000 CE and does not turn all southern forest into farmland.
135. Smith & Yarnell 2009, Initial formation of an indigenous crop complex
136. Valdez and Vivanco, Arqueologia de la Cuenca del Qaracha, Ayacucho, Peru — Survey documents Wari-period settlements around 600 CE controlling maize-producing soils at approximately 2800–3650 m. This is a secure later adoption horizon, not an earliest agriculture date.
137. Vidal Elgueta et al. 2019, Genetic and phenotypic diversity in ancient maize from Tarapaca, Atacama Desert, Chile — Ancient maize from settlements at 18–21 degrees south documents cultivation in hyperarid settings dependent on local water. The map marks limited valley / oasis niches, leaving the surrounding Atacama gray.
138. Watling et al. 2018, Direct archaeological evidence for Southwestern Amazonia as an early plant domestication and food production centre
139. Winchell et al. 2017, Sorghum domestication traits in eastern Sudan
140. Yang et al. 2020, Wupaer agriculture in the Kashgar Oasis
141. Zarrillo et al. 2008, Directly dated starch residues document early formative maize in tropical Ecuador — Direct cooking-residue chronology at Loma Alta supports domestic maize use by 5300–4960 cal BP in a varied crop economy. It does not establish one crop package across Ecuador.