Amazonian jungle is planted artificially

Today, one of the most important research questions for archaeology
and conservation ecology in Amazonia is to understand the influence
that past Indigenous populations had in transforming this vast
tropical forest. For a long time, the Amazon was considered to be
a sparsely populated pristine forest. In recent years, however,
archaeologists have shown that ancient human occupation deeply
altered the natural conditions of this basin, exerting profound
changes that transformed the normally poor acidic soils into dark,
organically rich and stable soils known as terras pretas
(https://bit.ly/3bDZRkA).
In addition to finding that tropical soils are much richer than
previously thought, archaeologists working in the Brazilian Amazon
began finding signs of pre-European human settlements that were
at odds with the notion of the tropical forest having been sparsely
settled in the past. Contrary evidence takes the form of areas of the
Amazon displaying large earthworks and ring villages, intensively
occupied settlements, and shell mounds, all of which demonstrate
active occupation over the the long duree. One of these sites with
long-term human occupation is Teotonio. 
The fieldwork in Teotonio in 2020 will involve surveying and
excavating this site, which is located in what was previously
a heavily forested area of northern Brazil. Like much of the forest
in this region, there has been extensive logging and burning of the
rainforest throughout Rondonia. While previously thought to have
been an empty wilderness in pre-contact times, it has become
increasingly clear that the Amazon has, first, a deep and ancient
pattern of human settlement dating back to 12000 years ago, and
second, that much of the Amazon "jungle" that we know today is,
in fact, an anthropogenic landscape. That is, the Amazon has been
modified extensively by indigenous populations for the past
12000 years. The changes that indigenous populations made in the
Amazon rainforest in the past were nowhere near the level of
intensive extraction we see going on with the massive deforestation
and burning today. Rather, indigenous populations increased the
overall biodiversity and quality of the soil in the many regions they
inhabited. In doing so, they produced terras pretas or anthropogenic
dark earths (ADEs), which are far more productive than natural soils.
Teotonio is the place where the earliest ADEs have been produced
in the Amazon, 5500 years ago. It is also a key place for the
identification of early plant domestication and management in South
America. The objective of our excavations in Teotonio will be to
collect samples from a 3200 years BP layer of ADEs with ceramics
associated with the early dispersal of speakers of the Arawak
language family, which, in the late fifteenth century AD, had
a range from the Central Andes to the Greater Antilles. 
The multidisciplinary fieldwork in Teotonio will also aim at
collecting data on past plant management with the aim of contributing
to the effort to understand how humans occupied, utilized,
transformed, and conserved the forest in the past as a basis for
making useful interventions in current policy-making concerning
the use and preservation of the Amazon rainforest.