Tham Khuyen Cave

Archaeology finds

In the mid-1960s excavators cut into the cave's sediments and found the teeth of hominoids. Reading them was not simple: most of the teeth in the cave belonged to orangutans, so any firm claim had to begin by setting out criteria to tell one tooth from another. Once sorted, the collection turned out to include teeth of Homo erectus alongside teeth of an extinct giant ape. In other words, before anything could be said about what the cave held, the sorting of tooth from tooth had to be done first.¹

A survey of Vietnamese Palaeolithic archaeology puts the count at ten Homo erectus teeth from Tham Khuyen and the neighbouring cave of Tham Hai. They did not lie apart but mixed with the bones of animals that no longer exist here: the giant panda, and the stegodon, an extinct relative of the elephant. That fauna is the context the teeth come with, and it shows they belong to a world quite unlike the one around the cave today.²

The age of that layer was measured two ways: electron spin resonance on tooth enamel and sediment, and uranium-series dating on the cave's flowstone. The main fossil-bearing deposits were laid down roughly 475,000 years ago. The figure sounds precise, but it comes with an error range of plus or minus 125,000 years. Over distances of time like that, archaeology says about and rarely says exactly.¹²