The Emptied Amazon · evidence ledger

Evidence

All 48 evidence records in this case's ledger. Every record carries an explicit direction, keeps what the source states separate from what we infer, and links its source and the claims it bears on. Supporting and undermining evidence get the same structure and the same seriousness.

Supports34 Qualifies4 Context10

Supports

34 records · strongest first

Records that favor a rung of the featured hypothesis.

Supports· decisiveAMZ-E009

Denevan rejects his own habitat-density method while retaining the order of magnitude

what the source states: "Consequently I now reject the habitat-density method I used in the past to estimate a Greater Amazonia population in 1492 of from 5.1 to 6.8 million. There was too much variability in densities in each habitat to be able to formulate meaningful average densities on the basis of a few sample densities." And: "I nevertheless still believe that a total of at least 5 to 6 million is reasonable."
what we infer: A number can remain plausible while the argument that generated it fails — the clearest documented example of why this case audits estimate dependencies rather than quoting totals.

William M. Denevan (2003)AI-verified citationAMZ-C012

Supports· strongAMZ-E001

LiDAR documents 432 earthworks and delimits a 183,000 km² Aquiry region

what the source states: "Our new LiDAR data, obtained from 10 ALS lines, document 432 earthworks, of which only 36 were previously known." LiDAR reveals "five times more earthworks in the deforested areas of block 1 than we had previously found along the same lines using satellite imagery"; the geographic circumscription "produced an area of about 183,000 km²," and the study estimates "approximately 24,000–30,000 earthworks, of which about two thirds belonged to the Aquiry."
limitations: The 24,000–30,000 figure is a block-extrapolation from sampled densities, as the paper states.

Martti Pärssinen (2026)AI-verified citationAMZ-C004

Supports· strongAMZ-E002

The paper's own single-family sensitivity collapses the population headline roughly fivefold

what the source states: "If, as said, about 25–60% (4,165–10,000) of these earthworks were in use in 100–300 ad, and if an average earthwork required 300 people to build and maintain it, we arrive at a total population of about 1.25–3 million." And: "Only if the very unlikely estimation that each approximately 25-m long house foundation (mound) belonged to a single family were true would the population be about 250,000–600,000 people without the invisibility effect of laser penetration, which would raise the population, in this case, to approximately 315,000–760,000."
what we infer: The estimate's span across its own stated assumptions — roughly fivefold — is the honest error bar, and it is what this case displays rather than the headline alone.
limitations: The authors label the single-family reading 'very unlikely'; the sensitivity is theirs, the emphasis is ours.

Martti Pärssinen (2026)AI-verified citationAMZ-C005

Supports· strongAMZ-E004

Southern-rim fortified villages dated ~AD 1250–1500, with a stated-assumptions population model

what the source states: "The results show that an 1800 km stretch of southern Amazonia was occupied by earth-building cultures living in fortified villages ~Cal AD 1250–1500." And: "Assuming site contemporaneity, the total population calculated for the UTB sites was 21,340… projected to the total area of potential occurrence of ditched enclosures in the SRA, the result is a population of 463,555… When projected to the total area of the SRA predicted to contain earthworks, the result is 1,087,150 inhabitants. Therefore, we assume that a population between ~500 thousand and 1 million for the SRA in late Pre-Columbian times (Cal AD 1250–1500) is a reasonable estimate."
limitations: Population figures rest on site contemporaneity, ethnographically-derived formulae, and MaxEnt-projected extrapolation — all stated by the authors.

Jonas Gregorio de Souza (2018)AI-verified citationAMZ-C006

Supports· strongAMZ-E005

Denevan: the extreme figures are absent from the Oviedo manuscript branch

what the source states: "There is no mention of 50,000 or 10,000 and 8,000 warriors as there is in the Medina (and Muñoz) versions… nor of villages 4 or 5 leagues in length. There is one mention of 5,000 warriors in the Oviedo version."
limitations: Verified from a Wayback abstract plus an OCR full-text copy; page numbers per the OCR pagination.

William M. Denevan (1996)AI-verified citationAMZ-C002

Supports· strongAMZ-E007

Nunes (1538) and the Ursúa accounts (1560) independently describe the populous middle Amazon

what the source states: "Diogo Nunes alcança a província de Machiparo em 1538, invadindo aldeias e capturando indígenas… Em 1560, seria a vez da expedição de Pedro de Ursúa… contando com dez relatos, sendo os de Vazquez, Almesto e Altamirano os mais completos." The accounts describe the middle Solimões as "uma das áreas mais densamente habitadas do rio-mar"; maize stores among the Yaguamales as "infinita"; straight roads "mui largos e bons, que eram ao modo dos Incas do Peru, exceto pelas paredes"; and turtle/fish abundance "na casa dos milhares."
what we infer: Independent witnesses, hostile to one another and writing for different crowns, repeat the mundane load-bearing features of Carvajal's picture. None of them repeats his extreme numbers.
limitations: Nunes's testimony survives as a letter of 1553/54 known through Porro's modern edition.
Fortifications and organized warfare are NOT among the verified common elements; the turtle-corral detail belongs to Acuña (1639).

Filippo A. Lopes (2024)AI-verified citationAMZ-C003

Supports· strongAMZ-E008

Newson's regional reconstruction: 88% and 62–64% declines by ~1700, by mixed mechanisms

what the source states: Table 1: Napo-Aguarico 49,000–51,000 → 6,000 circa 1700 (87.8–88.2% decline, depopulation ratio 8.3:1); Mainas 83,000–102,000 → 30,180–38,490 (62.3–63.6%). "Epidemics, enslaving raids, and missionization were also the major causes of Indian depopulation in the gobernación of Mainas… excessive demands for service provoked widespread unrest that culminated in a major revolt in 1635." Also: "most opted to flee from exposed locations along the… major rivers."
limitations: Upper-Amazon provinces with mission records; extension to the middle/lower Amazon is an extrapolation.

Linda A. Newson (2003)AI-verified citationAMZ-C010

Supports· strongAMZ-E010

7,363 sites: river distance is the dominant occupation predictor

what the source states: "We updated previously published models of the likely distributions of pre-Columbian people using 7,363 locations within Amazonia sensu stricto from the AmazonArch database." "Distance from river… was the most important predictor variable and accounted for 21.5% of the permutation importance in the pre-Columbian model." The updated models "differentiate probabilities of occupation in interfluvial areas that were more sparsely populated than those close to rivers."
limitations: Site databases inherit survey-effort bias toward accessible riverine areas.

Crystal N. H. McMichael (2025)AI-verified citationAMZ-C013

Supports· strongAMZ-E011

Fourteen-region phytolith/charcoal synthesis: little to no intensive-use signal in most sampled terra firme

what the source states: The cumulative program's regional sequences "particularly in interfluvial areas showed a dominance of diverse, often closed-canopy forests with little to no evidence for annual crop plants or significant forest clearings and few signs of persistent forest burning during the pre-Columbian era" — summarized as "little to no evidence for: 1) agriculture with annual seed and root crops, 2) significant forest clearing, 3) anthropic soils, 4) human enrichment of favored tree taxa such as palms, or 5) recurrent/extensive fires."
limitations: New fieldwork covers three regions; fourteen is the cumulative synthesis.
Soil-core sampling is spatially sparse; negative signals count only where the proxy could detect the activity.

Dolores R. Piperno (2024)AI-verified citationAMZ-C014

Supports· strongAMZ-E014

Casarabe: engineered year-round maize monoculture documented by phytoliths and hydraulic infrastructure

what the source states: "…the Casarabe culture invested heavily in landscape engineering, constructing a complex system of drainage canals (to drain excess water during the rainy season) and newly documented savannah farm ponds (to retain water in the dry season). Phytolith analyses of 178 samples from 18 soil profiles… record the singular and ubiquitous presence of maize (Zea mays)… our findings show how the Casarabe culture managed the savannah landscape for intensive year-round maize monoculture that probably sustained its relatively large population."
limitations: Casarabe florescence (500–1400 CE) ends before European contact.

Umberto Lombardo (2025)AI-verified citationAMZ-C007

Supports· strongAMZ-E016

Dating shows intermittent raised-field use in a few construction events

what the source states: "…radiocarbon and optically stimulated luminescence dating, show that the raised fields were in intermittent use since as early as AD 570–770… The data suggests that raised fields were built during a few separate construction events, probably linked to periods of more frequent and severe floods. The study challenges the most widely accepted theory that suggests that pre-Columbians were able to cultivate these fields on a continuous basis…"
limitations: Bermeo-area fields specifically; other complexes may differ.

Leonor Rodrigues (2015)AI-verified citationAMZ-C009

Supports· strongAMZ-E017

Belterra Plateau sites occupied ca. AD 1300 to seventeenth-century colonization, with dark earths, ponds, and trodden roads

what the source states: "…numerous archaeological sites, dating from ca. A.D. 1300 up to the time of European colonization in the seventeenth century, have been found in an upland area known as the Belterra Plateau, south of the present-day city of Santarém." Sites are "typically characterized by large quantities of pottery sherds… as well as extensive areas of anthropogenic soils (Terra Preta/Terra Mulata or Amazonian Dark Earth)," with "enclosed depressions, as well as ponds and trodden roads."

Per Stenborg (2018)AI-verified citationAMZ-C011

Supports· strongAMZ-E018

Cacoal dates Marajoara cultural permanence to AD 1300–1650 — into Portuguese contact

what the source states: "…o sítio PA-JO-49: Cacoal que, datado de 1.300 a 1.650 A.D., atesta a permanência da cultura Marajoara à época em que os Portugueses estabeleciam seus primeiros assentamentos na costa leste da Ilha de Marajó. Este período tardio… é caracterizado por continuidade cultural, mas também por mudanças sociopolíticas profundas."

Denise Pahl Schaan (2000)AI-verified citationAMZ-C011

Supports· strongAMZ-E022

Zooarchaeology: year-round fishing at Loma Salvatierra

what the source states: "The fishing practices in this area were studied on the basis of analysis of more than 17,000 fish remains recovered at Loma Salvatierra, a monumental mound located in an interfluvial area 50 km from the Mamoré River and occupied between 500 and 1400 AD" — demonstrating "that these regions contain year round resources," with lungfish (Lepidosiren paradoxa) and tiger-fish (Hoplias malabaricus) named among small-water-body dry-season resources.

Gabriela Prestes-Carneiro (2019)AI-verified citationAMZ-C026

Supports· strongAMZ-E073

Rostain 2024: Upano platform and road construction dated ca. 500 BCE to 300/600 CE — part 1

what the source states: Archaeological excavations date the Upano Valley "occupation from around 500 BCE to between 300 and 600 CE".
what we infer: Primary dating by the excavating team (almost 70 radiocarbon dates per the supplement); the end-date is a range, not a point.
limitations: Author-accepted manuscript; the revised sequence is promised in 'a subsequent paper'.

Stéphen Rostain (2024)AI-verified citationAMZ-C061

Supports· strongAMZ-E074

Huapula reoccupation of Upano mounds, 800–1200 CE — part 1

what the source states: Some mounds were "reoccupied after a hiatus by groups of the Huapula culture" between 800 and 1200 CE.
what we infer: Continuity of some occupation into the second millennium at Upano, at lower density; relevant to how long the valley's surfaces were forested before Colonial times.
limitations: Reoccupation extent ('some mounds') not quantified.

Stéphen Rostain (2024)AI-verified citationAMZ-C062

Supports· strongAMZ-E089

Oviedo supplemented the friar's text with what Orellana and his companions told him in Santo Domingo

what the source states: Medina quotes Oviedo: beyond what a devout Dominican friar wrote as eyewitness, he learned particulars afterwards in Santo Domingo "del mesmo capitán Francisco de Orellana é de otros caballeros" and hidalgos who came with him, which the friar had not written, and would tell them as he understood them from the captain and his consorts.
what we infer: Oviedo's version is therefore not independent of Orellana; where Oviedo differs from the T'Serclaes text, the difference may reflect Orellana's oral account. This is the transmission question AMZ-R002 must sort.
limitations: Oviedo quoted via Medina.

Gaspar de Carvajal (1542)UnverifiedAMZ-C074

Supports· strongAMZ-E091

Carvajal's closing protestation of truth

what the source states: Medina quotes the end of the Relación: the friar wrote it to tell and make known the truth in all of it, to forestall those who might tell the pilgrimage otherwise, "y es verdad en todo lo que yo he escrito y contado".
what we infer: A truth-oath is a genre convention of conquest narratives and adds no diagnostic weight; it is recorded because it is the author's own stated purpose.
limitations: Self-attestation; conventional.

Gaspar de Carvajal (1542)UnverifiedAMZ-C075

Supports· strongAMZ-E115

Rostain 2024: platforms and roads built by groups of the Kilamope and later Upano cultures

what the source states: The main text states that the original building of the earthen platforms and roads "was carried out by groups from the Kilamope and later Upano cultures".
what we infer: Cultural attribution by the excavating team, resting on the stratigraphic sequence it re-examined at the Sangay and Kilamope sites; its supplementary text S2 lists the Kilamope as the first mound builders and says the Upano built earthen mounds and were contemporaneous with or successors of the Kilamope.
limitations: Author-accepted manuscript; the dating sequence behind the attribution "was recently revised and will be presented in a subsequent paper" (supplementary text S2, p. 23).

Stéphen Rostain (2024)AI-verified citationAMZ-C086

Supports· moderateAMZ-E012

Domesticated tree species concentrate on and around archaeological sites

what the source states: "Across the basin, the relative abundance and richness of domesticated species increase in forests on and around archaeological sites."
limitations: See AMZ-E013: post-Columbian land use confounds the modern-composition signal.

Carolina Levis (2017)AI-verified citationAMZ-C008

Supports· moderateAMZ-E015

Raised fields proposed as flood-risk mitigation, built where no alternatives existed

what the source states: "Our alternative proposal suggests that raised field agriculture allowed pre-Columbian peoples to mitigate the risk of more intense and frequent flooding than is experienced today in the LM. We show that raised fields were built only in those areas where there were no alternatives…"

Umberto Lombardo (2011)AI-verified citationAMZ-C009

Supports· moderateAMZ-E019

Upper Xingu settlements inhabited 500–1770 CE in layouts matching living Kuikuro villages

what the source states: "Radiocarbon dating showed the settlements were inhabited from 500 C.E. to 1770 C.E. Like modern villages, the ancient cities were organized with pole-and-thatch huts around circular plazas, but they were more than 10 times larger." The team traced "a cluster of ancient cities that were laid out following the same structure of modern Kuikuro villages, but far larger."
limitations: Journalism summarizing the Heckenberger/Kuikuro research program; held at secondary-source weight pending the primary reports.

Sofia Moutinho (2024)AI-verified citationAMZ-C011

Supports· moderateAMZ-E020

Amazon-wide radiocarbon proxy fits logistic growth to carrying capacity before colonization

what the source states: "…our analyses document that the growth of pre-Columbian human population over the 1700 years prior to European colonization adheres to a logistic model of demographic growth. This suggests that, at an aggregate level, these pre-Columbian populations had potentially reached carrying capacity (however high) before the onset of European colonization." The terminal proxy decline "is likely to be an outcome of archaeological sampling biases, compounded by demographic decline and dispersal as Europeans enter the region."
limitations: SPDs are proxies for relative population change with stated biases — an aggregate signal, not a census.

Manuel Arroyo-Kalin (2021)AI-verified citationAMZ-C015

Supports· moderateAMZ-E021

Hancock's Amazon coverage and the platforming of Pärssinen and Ranzi

what the source states: Ancient Apocalypse: The Americas S2.E1 (aired 2024-10-16) lists in its top cast "Alceu Ranzi — (as Dr. Alceu Ranzi) — Self - Geographer & Paleontologist" and "Martti Pärssinen — (as Dr. Martti Pärssinen) — Self - Archaeologist & Anthropologist."
what we infer: Together with Hancock's first-party statement of America Before's Amazon coverage (AMZ-C018's anchor), this documents the advocacy record: the book preceded, and the series platformed, the researchers whose 2026 result now anchors this case.
limitations: Genealogy, not evidence: this record carries no weight for any empirical claim about the Amazon.

IMDb (2024)AI-verified citationAMZ-C018

Supports· moderateAMZ-E040

53 of 79 domesticated tree species significantly associated with modelled earthwork probability — part 2

what the source states: The occurrence and/or abundance of "53 of the 79 domesticated species showed significant association" with the predictive model of earthwork distribution.
what we infer: Corroborates AMZ-C008's tree-domestication leg with a different response variable (modelled earthwork probability rather than distance to known sites), but the species list is Levis et al. 2017's own and the authors overlap, so this is not independent of SRC-LEVIS-2017; the McMichael 2017 post-Columbian-management objection (AMZ-E013) applies equally here.
limitations: Association with a modelled probability surface, not with dated archaeological sites.
Same species list and overlapping authorship as SRC-LEVIS-2017; not an independent group.
Cannot separate pre- from post-Columbian management (see AMZ-E013).

Vinicius Peripato (2023)AI-verified citationAMZ-C033 AMZ-C008

Supports· moderateAMZ-E041

53 of 79 domesticated tree species significantly associated with modelled earthwork probability — part 5

what the source states: The 53 domesticated tree species significantly associated with earthwork occurrence probability are "likely suggesting past management practices" by pre-Columbian societies.
what we infer: Corroborates AMZ-C008's tree-domestication leg with a different response variable (modelled earthwork probability rather than distance to known sites), but the species list is Levis et al. 2017's own and the authors overlap, so this is not independent of SRC-LEVIS-2017; the McMichael 2017 post-Columbian-management objection (AMZ-E013) applies equally here.
limitations: Association with a modelled probability surface, not with dated archaeological sites.
Same species list and overlapping authorship as SRC-LEVIS-2017; not an independent group.
Cannot separate pre- from post-Columbian management (see AMZ-E013).

Vinicius Peripato (2023)AI-verified citationAMZ-C033 AMZ-C008

Supports· moderateAMZ-E076

Authors' assessment: Upano is the earliest and largest low-density agrarian urbanism documented in Amazonia so far — part 1

what the source states: Other monumental sites of Amazonia are all more recent than the Upano sites and "significantly less dense in terms of features", and, until proven otherwise, not embedded within such a vast and dense communication network.
what we infer: A comparative claim by the discoverers, explicitly time-bounded ('so far'); the Aquiry peak (AD 100–300, AMZ-C004/E003) overlaps its later phase, so 'earliest' depends on definitions of urbanism.
limitations: Authors' interpretive superlative; comparison set is the supplement's four sites.

Stéphen Rostain (2024)AI-verified citationAMZ-C064

Supports· moderateAMZ-E080

Medina: Gómara called Orellana's relación 'mentirosa' — the invention charge began with the captain's narrative

what the source states: Medina writes that López de Gómara and Herrera knew Orellana's relación, and that Gómara "la cita dándole el calificativo de «mentirosa»", though, as Pinelo-Barcia observed, without stating his grounds.
what we infer: The object of Gómara's charge is Orellana's relación, not the Carvajal text the ledger reads; the sixteenth-century 'invention' charge therefore does not directly impeach Carvajal. Medina's reading of Gómara is second-hand here; Gómara's own passage (Ribadeneyra ed. p. 210, per Medina) is not in the ledger.
limitations: Gómara's text is quoted by Medina, not read directly.

Gaspar de Carvajal (1542)UnverifiedAMZ-C068

Supports· moderateAMZ-E082

Medina attributes the 'mentirosa' charge to the Amazons claim

what the source states: Medina says the ground for Gómara's charge is 'not difficult to discover': Carvajal in his notes and Orellana at court had spoken of Amazons, and he quotes Gómara — "fué afirmar que había en este río amazonas" — as the disparate that drew the accusation.
what we infer: This is Medina's inference from Gómara's text, which Medina himself notes does not state its grounds.
limitations: Inference by the 1894 editor, not a statement by Gómara of his reasons.

Gaspar de Carvajal (1542)UnverifiedAMZ-C069

Supports· moderateAMZ-E093

Herrera followed Carvajal's Relación almost to the letter (Medina)

what the source states: Medina: Antonio de Herrera had the Relación before him "y la sigue muy de cerca, casi al pie de la letra", in keeping with his method of extracting documents; Medina cites three 'Afirma el P. Carvajal' passages from Década V, lib. VIII.
what we infer: Any narrative derived from Herrera (e.g. Markham 1859's Orellana text) is not an independent witness to the voyage but a redaction of Carvajal.
limitations: Medina's characterization; the collation is not printed.

Gaspar de Carvajal (1542)UnverifiedAMZ-C077

Supports· moderateAMZ-E113

Oviedo's endorsement of Carvajal rests on the friar's wounds — part 1

what the source states: Medina quotes Oviedo (Historia general, t. IV, p. 574): the friar "debe ser creído en virtud de aquellos dos flechazos", one of which took his eye.
what we infer: Credibility evidence at second hand: Oviedo vouches for the man on the basis of injuries and reputation reported by others, not personal acquaintance or independent knowledge of the river. It should stay separate from diagnosticity for AMZ-C017.
limitations: Oviedo quoted via Medina; the Oviedo volume is blocked in this ledger.

Gaspar de Carvajal (1542)UnverifiedAMZ-C072

Supports· moderateAMZ-E114

Oviedo's endorsement of Carvajal rests on others' testimony to his character — part 2

what the source states: Medina quotes Oviedo (Historia general, t. IV, p. 574): beyond the wounds, Oviedo would believe the friar on the strength of what his authority and person deserve, "ques mucho segund afírman los que le han tractado".
what we infer: Credibility evidence at second hand: Oviedo vouches for the man on the basis of injuries and reputation reported by others, not personal acquaintance or independent knowledge of the river. It should stay separate from diagnosticity for AMZ-C017.
limitations: Oviedo quoted via Medina; the Oviedo volume is blocked in this ledger.

Gaspar de Carvajal (1542)UnverifiedAMZ-C085

Supports· weakAMZ-E072

Achmatowicz 2018 assesses Carvajal's manuscript as a trustworthy source on geographic grounds

what the source states: The abstract says the article is devoted to the verisimilitude of the principal source for Orellana's exploration, Carvajal's eyewitness account, verifying it through a careful study of the geographic reference points in the narration and showing that the manuscript "se puede considerar como una fuente digna de confianza".
what we infer: A published scholarly assessment converging with AMZ-C017's credibility leg, reached by a different route (geography and league distances rather than manuscript branches). Abstract-only; the argument and its route conclusions were not read, so weight is minimal.
limitations: Abstract only; body not read.
Assesses geographic plausibility, not the population figures.
Second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-140447, verify-v6) found the passage bears in different directions on the claims the record named; this record carries "supports" toward AMZ-C065, the rest went to a record of its own at intake: The abstract directly supports AMZ-C065's claim that Achmatowicz assesses Carvajal as trustworthy via geographic verification. But it says nothing about the specific qualitative-versus-numerical distinction in AMZ-C017 (i.e., that Carvajal is credible on social geography while his numbers are textually unstable); it only asserts general trustworthiness based on geography, so it bears on that claim only as context, not direct support.

Jerzy Achmatowicz (2018)AI-verified citationAMZ-C065

Supports· weakAMZ-E112

Medina's two caveats on the Relación: supernatural attributions and partisanship for Orellana — part 2 — toward AMZ-C076

what the source states: In places the author attributes certain events to supernatural causes: "el autor atribuya ciertos hechos á causas sobrenaturales".
what we infer: The two caveats limit the scope of the friar's reliability (causation and partisanship) without touching the descriptive social geography AMZ-C017 rests on.
limitations: Editor's general judgement; no specific passages cited.
Second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-160114, verify-v6) found the passage bears in different directions on the claims the record named; this record carries "supports" toward AMZ-C076, the rest went to a record of its own at intake: The quoted phrase is genuinely Medina's and appears near the page break before 'Documentación del Viaje xiii', consistent with the p. xii locator, and it faithfully restates his observation that Carvajal occasionally attributes events to supernatural causes, so it directly supports AMZ-C076, not merely 'qualifies' it. For AMZ-C017 (about Carvajal's qualitative credibility vs. numeric unreliability), this observation about supernatural attributions is tangential — Medina in fact cites it only to say it does NOT undermine Carvajal's overall trustworthiness — so it bears on C017 only as background context, not as a genuine qualification of the specific claim about numeric vs. qualitative reliability.

Gaspar de Carvajal (1542)UnverifiedAMZ-C076

Qualifies

4 records · strongest first

Records that narrow, complicate, or bound what another record can carry.

Qualifies· strongAMZ-E003

The Aquiry demographic peak is dated AD 100–300 — a millennium before Orellana

what the source states: "The densest overlap of calibrated dates occurs at around 100–300 ad, both chronologically and spatially… our results strongly suggest that between ad 100 and 300 the population of the Aquiry was approximately 1.25–3 million."
what we infer: Superb evidence against ecological-impossibility arguments; weak direct evidence about the world Carvajal saw in 1542. Spending early-dated grandeur as contact-era corroboration is the chronology error this case is built to avoid.

Martti Pärssinen (2026)AI-verified citationAMZ-C004 AMZ-C017

Qualifies· moderateAMZ-E006

The bluff model: sporadic riverine settlement concentrated where channels meet bluffs

what the source states: "However, bluff occupation was sporadic rather than continuous, with large settlements mostly located where main river channels impinged against bluffs."
what we infer: A settlement geography of dense reaches alternating with empty ones is exactly the pattern Carvajal reports — including his empty stretches — which turns his account from "continuous metropolis" rhetoric into a testable spatial prediction.

William M. Denevan (1996)AI-verified citationAMZ-C001

Qualifies· moderateAMZ-E013

Technical Comment: post-Columbian activities likely played the larger role in the tree signal

what the source states: "The study, however, downplays five centuries of human influence following European arrival to the Americas. We show that the effects of post-Columbian activities in Amazonia are likely to have played a larger role than pre-Columbian ones in shaping the observed floristic patterns."

Crystal N. H. McMichael (2017)AI-verified citationAMZ-C008

Qualifies· weakAMZ-E111

Medina's two caveats on the Relación: supernatural attributions and partisanship for Orellana — part 3

what the source states: In other places the author shows himself an enthusiastic admirer of his chief and countryman: "se maniñeste entusiasta admirador de su jefe y compatriota".
what we infer: The two caveats limit the scope of the friar's reliability (causation and partisanship) without touching the descriptive social geography AMZ-C017 rests on.
limitations: Editor's general judgement; no specific passages cited.
Second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-160114, verify-v6) found the passage bears on AMZ-C017 and not on AMZ-C076; the link dropped at intake: The quoted span (admiration of his chief) is accurately taken from Medina's introduction and fairly paraphrased, and the locator is close to correct; it plausibly qualifies Carvajal's credibility assessment relevant to AMZ-C017. However, the record's title and framing imply it also documents the 'supernatural causes' caveat for AMZ-C076, but the actual quoted text only covers the admiration clause, not the supernatural-attribution clause, so it does not itself support AMZ-C076.

Gaspar de Carvajal (1542)UnverifiedAMZ-C017

Context

10 records · strongest first

Background that informs the case without pushing either way.

Context· strongAMZ-E075

Huapula reoccupation of Upano mounds, 800–1200 CE — part 2

what the source states: Huapula ceramic is "characterized by decorations based on the corrugated modality using wavy patterns".
what we infer: Continuity of some occupation into the second millennium at Upano, at lower density; relevant to how long the valley's surfaces were forested before Colonial times.
limitations: Reoccupation extent ('some mounds') not quantified.
Direction set to "context" (from "supports") by the second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-140447, verify-v6) at intake: The quoted sentence only describes the corrugated, wavy-pattern decoration typical of Huapula pottery; it does not itself assert that mounds were reoccupied by Huapula groups between 800 and 1200 CE, which is stated elsewhere in the supplement. As such the passage identifies/dates the Huapula culture but does not directly support the reoccupation claim, so it functions as context rather than support.

Stéphen Rostain (2024)AI-verified citationAMZ-C062

Context· moderateAMZ-E038

Comparator: a basin-wide 10–24k undiscovered-earthwork prediction beside the Aquiry 24–30k regional prediction — part 1

what the source states: The predictive model "predicts the number of yet undiscovered pre-Columbian structures as 10,272" to 23,648, with 95% probability, for Amazonia's 6.7 million km² extent.
what we infer: Editor's comparison: SRC-PARSSINEN-2026 predicts roughly 24,000–30,000 earthworks within a ~183,000 km² Aquiry area alone — more than Peripato's upper bound for the entire basin, over an area about twice Peripato's high-probability rectangle. The two are not strictly commensurable (different earthwork definitions, data, and estimators; Peripato's 2023 model predates the 2026 LiDAR), so this does not undermine what AMZ-C004 states the 2026 study predicts. It does show that earthwork totals differ several-fold between published models, which AMZ-R004-style dependency work should address. Zero diagnosticity for the truth of C004 as worded; logged as the comparator the report sought.
limitations: Different operational definitions of 'earthwork' and different survey data between the two studies.
Peripato's model predates and does not incorporate the 2026 LiDAR campaign.

Vinicius Peripato (2023)AI-verified citationAMZ-C004

Context· moderateAMZ-E039

Comparator: a basin-wide 10–24k undiscovered-earthwork prediction beside the Aquiry 24–30k regional prediction — part 2

what the source states: Nearly all the highest-probability cells (≥ 25% predicted probability) occur in a 94,713-km² "rectangle that overlays a significant portion of the Brazilian state of Acre."
what we infer: Editor's comparison: SRC-PARSSINEN-2026 predicts roughly 24,000–30,000 earthworks within a ~183,000 km² Aquiry area alone — more than Peripato's upper bound for the entire basin, over an area about twice Peripato's high-probability rectangle. The two are not strictly commensurable (different earthwork definitions, data, and estimators; Peripato's 2023 model predates the 2026 LiDAR), so this does not undermine what AMZ-C004 states the 2026 study predicts. It does show that earthwork totals differ several-fold between published models, which AMZ-R004-style dependency work should address. Zero diagnosticity for the truth of C004 as worded; logged as the comparator the report sought.
limitations: Different operational definitions of 'earthwork' and different survey data between the two studies.
Peripato's model predates and does not incorporate the 2026 LiDAR campaign.

Vinicius Peripato (2023)AI-verified citationAMZ-C004

Context· weakAMZ-E077

Achmatowicz 2018 assesses Carvajal's manuscript as a trustworthy source on geographic grounds — toward AMZ-C017

what the source states: The abstract says the article is devoted to the verisimilitude of the principal source for Orellana's exploration, Carvajal's eyewitness account, verifying it through a careful study of the geographic reference points in the narration and showing that the manuscript "se puede considerar como una fuente digna de confianza".
what we infer: A published scholarly assessment converging with AMZ-C017's credibility leg, reached by a different route (geography and league distances rather than manuscript branches). Abstract-only; the argument and its route conclusions were not read, so weight is minimal.
limitations: Abstract only; body not read.
Assesses geographic plausibility, not the population figures.
Second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-140447, verify-v6) found the passage bears in different directions on the claims the record named; this record carries "context" toward AMZ-C017, the rest went to a record of its own at intake: The abstract directly supports AMZ-C065's claim that Achmatowicz assesses Carvajal as trustworthy via geographic verification. But it says nothing about the specific qualitative-versus-numerical distinction in AMZ-C017 (i.e., that Carvajal is credible on social geography while his numbers are textually unstable); it only asserts general trustworthiness based on geography, so it bears on that claim only as context, not direct support.

Jerzy Achmatowicz (2018)AI-verified citationAMZ-C017

Context· weakAMZ-E099

Genealogy of the 'invention' account: the earliest lie-charge targeted Orellana and the Amazons episode — part 2

what the source states: Gómara's objection to Orellana was that among the nonsense he spoke "fué afirmar que había en este río amazonas" with whom he and his companions fought.
what we infer: Background for the case's 'invention' account: the sixteenth-century doubt was about the Amazons, not about populous settlements. Zero diagnosticity for the truth of Carvajal's social geography; it locates where the doubt began.
limitations: Medina's paraphrase and selection of Gómara; interpretive.

Gaspar de Carvajal (1542)UnverifiedAMZ-C017

Context· weakAMZ-E100

Genealogy of the 'invention' account: the earliest lie-charge targeted Orellana and the Amazons episode — part 3

what the source states: Carvajal in his account "se limita á consignar las respuestas que el indio interrogado por Orellana dio" about the way of life of those women, without saying whether he himself believed the tale.
what we infer: Background for the case's 'invention' account: the sixteenth-century doubt was about the Amazons, not about populous settlements. Zero diagnosticity for the truth of Carvajal's social geography; it locates where the doubt began.
limitations: Medina's paraphrase and selection of Gómara; interpretive.

Gaspar de Carvajal (1542)UnverifiedAMZ-C017

Context· weakAMZ-E105

Contemporary character endorsement of Carvajal (credibility, not diagnosticity) — part 1

what the source states: Oviedo judges that Carvajal is worthy to write of the Indies and "debe ser creído en virtud de aquellos dos flechazos", one of which took out his eye.
what we infer: This bears on the credibility of the witness, not on whether any particular observation is true; it adds essentially no diagnostic weight to AMZ-C017 and is entered so that the record shows what the contemporary endorsement actually rests on.
limitations: Reputation evidence; no independent check on content.
Direction set to "context" (from "supports") by the second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-160114, verify-v6) at intake: The quote is genuinely Oviedo's, correctly attributed and located, and accurately paraphrased as a general character endorsement of Carvajal's trustworthiness. But it is a generic reputational vouching for Carvajal's honesty as a writer, not evidence bearing on the specific claim that his qualitative social geography is credible while his numeric claims are textually unstable — Oviedo draws no such distinction, so the passage is context for Carvajal's general credibility rather than support for this particular nuanced claim.

Gaspar de Carvajal (1542)UnverifiedAMZ-C017

Context· weakAMZ-E106

Contemporary character endorsement of Carvajal (credibility, not diagnosticity) — part 2

what the source states: Oviedo adds that Carvajal's authority and person deserve much, "segund afírman los que le han tractado", and that he would believe him more than those who write novels about the Indies from Europe without having come to them.
what we infer: This bears on the credibility of the witness, not on whether any particular observation is true; it adds essentially no diagnostic weight to AMZ-C017 and is entered so that the record shows what the contemporary endorsement actually rests on.
limitations: Reputation evidence; no independent check on content.
Direction set to "context" (from "supports") by the second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-160114, verify-v6) at intake: The quote is genuine and accurately paraphrased, and the locator is plausible, but Oviedo's remark is a blanket personal-character endorsement ('he should be believed') that does not distinguish between Carvajal's qualitative descriptions and his numerical claims. Since AMZ-C017 specifically asserts credibility on social geography while flagging numbers as unstable, a general reputation defense does not selectively support that split; it is better read as context about Carvajal's contemporaneous standing rather than direct support for the claim's particular qualitative/quantitative distinction.

Gaspar de Carvajal (1542)UnverifiedAMZ-C017

Context· weakAMZ-E109

Medina's two caveats on the Relación: supernatural attributions and partisanship for Orellana — part 1

what the source states: Limited to the chronicle of the voyage, the Relación deserves complete faith: "no hay motivo alguno por el cual no nos merezca completa fe".
what we infer: The two caveats limit the scope of the friar's reliability (causation and partisanship) without touching the descriptive social geography AMZ-C017 rests on.
limitations: Editor's general judgement; no specific passages cited.
Second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-160114, verify-v6) found the passage bears on AMZ-C017 and not on AMZ-C076; the link dropped at intake: The quoted sentence is Medina's general endorsement of the chronicle's credibility as to voyage events, not a statement distinguishing qualitative reliability from numerical unreliability, so for C017 it is background context rather than a true qualifier of that specific distinction; for C076, the quoted material does not mention supernatural attributions at all (that phrase appears only in the surrounding, unquoted text), so this record's sourceStatement does not actually establish the claim about Carvajal invoking supernatural causes.
Direction set to "context" (from "qualifies") by the second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-160114, verify-v6) at intake: The quoted sentence is Medina's general endorsement of the chronicle's credibility as to voyage events, not a statement distinguishing qualitative reliability from numerical unreliability, so for C017 it is background context rather than a true qualifier of that specific distinction; for C076, the quoted material does not mention supernatural attributions at all (that phrase appears only in the surrounding, unquoted text), so this record's sourceStatement does not actually establish the claim about Carvajal invoking supernatural causes.

Gaspar de Carvajal (1542)UnverifiedAMZ-C017

Context· weakAMZ-E110

Medina's two caveats on the Relación: supernatural attributions and partisanship for Orellana — part 2

what the source states: In places the author attributes certain events to supernatural causes: "el autor atribuya ciertos hechos á causas sobrenaturales".
what we infer: The two caveats limit the scope of the friar's reliability (causation and partisanship) without touching the descriptive social geography AMZ-C017 rests on.
limitations: Editor's general judgement; no specific passages cited.
Second reader (claude-sonnet-5, 2026-09-17, run 2026-09-17-verify-pre-columbian-amazon-160114, verify-v6) found the passage bears in different directions on the claims the record named; this record carries "context" toward AMZ-C017, the rest went to a record of its own at intake: The quoted phrase is genuinely Medina's and appears near the page break before 'Documentación del Viaje xiii', consistent with the p. xii locator, and it faithfully restates his observation that Carvajal occasionally attributes events to supernatural causes, so it directly supports AMZ-C076, not merely 'qualifies' it. For AMZ-C017 (about Carvajal's qualitative credibility vs. numeric unreliability), this observation about supernatural attributions is tangential — Medina in fact cites it only to say it does NOT undermine Carvajal's overall trustworthiness — so it bears on C017 only as background context, not as a genuine qualification of the specific claim about numeric vs. qualitative reliability.

Gaspar de Carvajal (1542)UnverifiedAMZ-C017

refused evidence (3) — kept as tombstones with the reason; they carry no weight and are counted nowhere

AMZ-E086Rejectedwas supports → AMZ-C072

Oviedo's endorsement of Carvajal rests on the friar's wounds and others' testimony to his character

Medina quotes Oviedo (Historia general, t. IV, p. 574): the friar "debe ser creído en virtud de aquellos dos flechazos", one of which took his eye, and on the strength of what his authority and person deserve, "ques mucho segund afírman los que le han tractado".

Refused by the operator on 2026-09-17 (session_01AiXD4y5Y91KC7iM3uBhWmu, operator-by-hand-v1), answering the GPT-5.6 Sol seat's objection on #353 (panel-v3, judged at 86a8709): not one observation — two grounds of Oviedo's endorsement in one record; split into AMZ-E113 (the wounds) and AMZ-E114 (the character testimony), each carrying its own quote from the same passage (§3.2).

AMZ-E107Rejectedwas supports → AMZ-C017

Contemporary character endorsement of Carvajal (credibility, not diagnosticity) — part 3

Limited to the chronicle of the voyage's events, the Relación deserves complete faith: "no hay motivo alguno por el cual no nos merezca completa fe".

Refused by the operator on 2026-09-17 (session_01AiXD4y5Y91KC7iM3uBhWmu, operator-by-hand-v1), answering the GPT-5.6 Sol seat's objection on #353 (panel-v3, judged at 86a8709): a duplicate of AMZ-E109 — the same sentence of Medina (p. xii), the same quote, the same claim, admitted by the same run as "context" there and "supports" here. One record of one observation stands, under the direction the run gave the split of the parent record whose parts are AMZ-E109, AMZ-E110 and AMZ-E111; this one is a tombstone (§3.10).

AMZ-E108Rejectedwas supports → AMZ-C017

Contemporary character endorsement of Carvajal (credibility, not diagnosticity) — part 4

This complete faith is granted even though the author at times attributes certain deeds to supernatural causes and "se maniñeste entusiasta admirador de su jefe y compatriota".

Refused by the operator on 2026-09-17 (session_01AiXD4y5Y91KC7iM3uBhWmu, operator-by-hand-v1), answering the GPT-5.6 Sol seat's objection on #353 (panel-v3, judged at 86a8709): not one observation — it bundles the complete-faith judgment (AMZ-E109), the supernatural attributions (AMZ-E110) and the partisanship for Orellana (AMZ-E111), each of which stands as its own record from the same run and the same page (§3.2, §3.5).