Archaeologists have found the bones of "almost too many" mammoths to excavate at an airport under construction just north of Mexico City

ABC:

[They were found] near human-built ’traps’ where more than a dozen mammoths were found last year.

Both discoveries reveal how appealing the area — once a shallow lake — was for the mammoths, and how erroneous was the classic vision of groups of fur-clad hunters with spears chasing mammoths across a plain. Humans may have been smarter — and mammoths clumsier — than people had previously thought.

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Mammoth bones have always been so numerous in the area that the Aztecs, who ruled the Mexico Valley between 1325 and 1521, recorded having found the enormous bones; Sánchez Nava said the Aztecs interpreted them as proof of legends that giants had once populated the valley.