Tropical forests will still exist in 2100

Our colleague, the archaeologist Santiago Rivas, recently made a remarkable discovery. On a small plateau above the outskirts of Iquitos, a town in the northern Peruvian Amazon, he found a layer in the soil which contained small pieces of ceramic pottery, that were around 1,800-years-old. Digging deeper, he found another layer of soil, this time containing pottery that was about 2,500 years old.

This is the archaeological site at Quistococha which has been occupied for at least the past 3,000 years. The pottery fragments are beautifully decorated, sometimes with subtle geometric scratch marks or boldly painted with bright red patterns. Not all of the fragments are small: erosion revealed the rim of a large cooking pot that would have been 40cm across when it was intact. Large pots were supported on an open fire by “elephant feet”: small clay pot rests also found in the archaeological layers.

As a place for people to live, Quistococha would have had many advantages. It is located on a terrace above a fertile floodplain of the Amazon which is ideal for growing maize, while the surrounding palm swamp provides fruits and fibres. Just below the terrace, fresh water flows out of a