Deep Time · Side by side

Two chapters, the same questions asked of both

Put two Deep Time chapters next to each other — their evidence base, the dating methods behind them, the live debates, and the questions still open.

Documented2000 BCE – 1500 CE

Maya

A fully deciphered script, precise astronomy, and a still-contested collapse.

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Documented1300 – 1521 CE

Aztec

Lake-city agriculture, tribute economics, and codices written on both sides of conquest.

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The evidence base

A deciphered hieroglyphic script, dated monuments, four surviving codices, lidar-mapped settlement, and continuing Maya communities.

Excavations in and beneath Mexico City, indigenous and colonial-era codices, Nahuatl-language texts, and Spanish accounts written by participants and their descendants.

How we know
MethodWhat it constrains
Epigraphic deciphermentCarved stelae, lintels and painted ceramicsYields dynastic history in the rulers' own terms — which is court history, with its own agenda.
Lidar landscape surveyAirborne laser returns under forest canopyMaps structures and field systems at scale. Dating still requires ground excavation.
Palaeoclimate reconstructionLake sediment and speleothem records from the lowlandsDocuments drought intervals overlapping the Classic decline.
MethodWhat it constrains
Urban excavationTemplo Mayor precinct and offering depositsDirectly tests textual descriptions of ritual. Much of the city remains under a modern capital.
Codex analysisPictorial manuscripts and Nahuatl alphabetic textsPreserves indigenous accounts; most surviving copies were produced under colonial conditions.
BioarchaeologySkeletal remains from ritual and burial contextsEstablishes practice and demography without confirming reported totals.
Where specialists disagree
  • What drove the Classic-period collapse?

    Drought, warfare, soil exhaustion and political fragmentation interact differently by region.

  • How much of the codical tradition can be reconstructed?

    Four codices survive from what was clearly a much larger literature.

  • What was the scale of human sacrifice?

    Skull-rack excavation confirms the practice; Spanish-reported totals remain contested.

  • How coercive was the tribute empire?

    Provincial evidence shows a spectrum from garrisoned control to negotiated tribute.

Still open
  • How were regional political networks structured between capitals?
  • How large were peak populations, now that lidar has changed the baseline?
  • How much surviving text remains unexcavated or unreadable?
  • How much of Tenochtitlan is recoverable beneath Mexico City?
  • How did the lake hydraulic system function in detail?
  • What did pre-contact population figures actually look like?