Recent work on Amazonian Sites

With regard to the Hancockian ideas of potential "Lost Ice Age Civilizations" in the Amazon, it might be worth looking at some reports of the recenyt discoveries that he is using gto leverage these claims. Above all this concerns the earthworks ("geoglyphs") discovered in several regions, in pareticular those found mainly between the Acre and Iquiri rivers in the Brazilian state of Acre, where they were apparently first documented in the 1970s when researcher Ondemar Dias noted several sites in the land of Acre while carrying out his activities for the National Program for Archaeological Research in the Amazon Basin (Pronapaba). In the region there are now known at least 300 groups of such earthworks in areas of interfluves, igarapés springs, and floodplains. There are estimated more than 410 geoglyphs in the state spread over around 300 archaeological site that show that the Amazon floodplains and non-flooded terra firme hinterlands were not completely covered by pristine forests threoughout most of the Hoplocene as originally believed. The sites in Acre (Parsinen et al. 2020 ) all

"seem to belong to the same ceramic tradition, with affiliations to ancient, Western Amazonian Formative styles. Ceramics dating to c. 2000 BP and resembling other widespread Amazonian styles, including Incised-Rim, Polychrome and Corrugate styles, have also been recovered during excavations of sites, such as Severino Calazans and Tequinho (Pärssinen and Ranzi 2020). Calibrated radiocarbon dates indicate that the first Acre earthworks were initiated by c. 2500 BP, with construction continuing until 1000 BP. Some were still in use at the end of the thirteenth century AD and, according to recent radiocarbon dating, were re-used until as recently as the nineteenth century (Saunaluoma et al. 2018)".

Amazonia, or at least part of it, was already occupied by hunter gatherers by the Late Pleistocene period, c. 13 000–10 000 BP, and in the Early Holocene, c. 10 000– 8000 BP including (it is inferred from charcoal evidence) on the Severino Calazans site in eastern Acre, dating to as early as c. 10 000 cal BP It appears that below the known earthwork was a cultural layer that pre-dates it by more than 7000 years [use of the site continued, with some possible intervals, until the earthworks were abandoned]. This represents some of the first evidence for an Early Holocene human presence from the Amazonian upland (terra firme) away from the major river valleys (Parssinen et al. 2020, 1541).

Over large parts of Amazonia, archaeological research over the past quarter of a century has revedaled many areas of the specific Amazonian Dark Earths (terra preta) resulting from ancient Amerindian landscape management practices, both on riverine bluffs as well as in upland terra firme forests near Amazonia’s main riverine routes (Woods and Denevan 2009). These dark earths are anthropogenic, highly fertile soils created by centuries of soil mulching over the otherwise poor Amazonian latosols. These anthropogenic black soils were created by Amerindians using fires to produce pyrogenic carbon, which lowers soil pH and gives stability to soil nutrients and micro-organisms. It is worth looking at the distributions of these site types in the region. The earthworks (revealed by deforestation as well as LIDAR surveys under the forest canopy) occur mostly in the southern regions of Amazonia (Fig 1)

Fig 1 (de Souza et al 2018)

Fig 2 Forest destruction hotspots, 13% irreparably destroyed (Mongabay). This is where the earthwork sites are becoming visible. 

Fig 3, differentiating the record (Walker et al 2023)

 REFERENCES

de Souza, J.G., Schaan, D.P., Robinson, M. et al. Pre-Columbian earth-builders settled along the entire southern rim of the Amazon. Nat Commun 9, 1125 (2018). https://doi.org/10.1038/s41467-018-03510-7

Hodgson Camilla and Campbell Chris 2022, ' Climate graphic of the week: Amazon rainforest loss fuelled by destruction around roads Brazil accounted for more than 40% of global tropical forest loss in 2021', Financial Times May 7 2022

[Pärssinen, M. and A. Ranzi. 2020. Mobilidade cerimonial e a emergência do poder político com as primeiras estradas conhecidas do oeste amazônico (2000 A.P.), in R. Vilaça & R. Simas de Aguiar (ed.) (I) Mobilidades na Pré-história: Pessoas, recursos, objetos, sítios e territórios: 307–49. Coimbra: Coimbra University Press.]

Pärssinen, Martti; Balée, William; Ranzi, Alceu; Barbosa, Antonia (2020). "The geoglyph sites of Acre, Brazil: 10 000-year-old land-use practices and climate change in Amazonia" (PDF). Antiquity. 94 (378): 1538–1556. doi:10.15184/aqy.2020.208.

[Saunaluoma, S., M. Pärssinen and D. Schaan. 2018. Diversity of pre-colonial earthworks in the Brazilian state of Acre, South-western Amazonia. Journal of Field Archaeology 43: 362–79. https://doi.org/10.1080/00934690.2018. 1483686]

Walker RS, Ferguson JR, Olmeda A, Hamilton MJ, Elghammer J, Buchanan B. 2023. Predicting the geographic distribution of ancient Amazonian archaeological sites with machine learning. PeerJ 11:e15137 https://doi.org/10.7717/peerj.15137

[Woods, W., Denevan, W. (2009). Amazonian Dark Earths: The First Century of Reports. In: Woods, W.I., Teixeira, W.G., Lehmann, J., Steiner, C., WinklerPrins, A., Rebellato, L. (eds) Amazonian Dark Earths: Wim Sombroek's Vision. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-9031-8_1]