Forest island in the grassland
Every spring, rain and melted snow flood the vast grasslands between the Andes Mountains and the Amazon rainforest in northern Bolivia, but thousands of "forest islands" covered by trees stand there. "Lin Island" is a high forest area with a diameter of about 70 meters, a few feet above the submerged grassland. Humberto Lombardo of the University of Bern, Switzerland, said: “They are like forest islands on the prairie.” In 2006, Lombardo first set foot on the forest islands of the Greater Moxos region. How did he feel about these forests? Bai Ran was very confused. He recalled that as a geographer, I had no idea how to explain them.
There is a theory that in the past few centuries, ranchers cut down the lush rainforest to create pastures, but left small forests of about 300 trees scattered around. But this does not explain why these trees grow higher.
Facts have proved that forest islands were built by humans and are much older than people think.
Judging from previous research papers, experts believe that the southwestern Amazonian region may also be the center of early plant domestication, because a large number of wild relatives of contemporary crops have been found here. Now, experts have confirmed this inference after studying these "forest islands".
This aerial photo from the South American prairie shows isolated forest islands growing on vast grasslands. Scientists explain these forest islands: ancient humans planted and cultivated crops here, making them the oldest domestication center in history.
In 2012, the archaeologists Jose Capriles and Lombardo of Pennsylvania State University began to excavate T works. They confirmed that the three islands were built by ancient people. In this new study, Lombardo used Google Maps to map 6,643 forest islands, which are about the same size as Illinois.
Researchers investigated some sites and collected samples on 82 islands to determine whether these islands were formed naturally or by humans thousands of years ago. The results of the study showed that obvious traces of human activities, such as charcoal, shells and bones, were found on 64 islands. They estimate that among the 6,643 forest islands, at least 4,700 forest islands have been inhabited by humans for thousands of years. The wastes discarded by human beings continue to accumulate, forming raised areas to withstand frequent floods, and later overgrown with trees.
Their garden is filled with fertile compost, allowing trees to take root above the seasonal flood line. Artificial forest islands not only did not damage the environment, but enhanced biodiversity and provided habitats for today’s rare species.
Archaeological excavations on the forest island of the Moxos steppe in Bolivia have revealed the existence of humans in the early and mid Holocene, including tombs.
Humberto Lombardo of the University of Bern collects sediment cores in the Moxos steppe.
Capriles, assistant professor of anthropology at Pennsylvania State University, is conducting excavations in the San Pablo Forest Islands.
In further research, experts used radiocarbon dating to determine the age of charcoal and eggshells. The results show that as early as 10350 years ago, shortly after the ice age, there were human activities on the "Lindao".
Plant cultivation existed before 1035
After further research, experts began to look for plant rocks in the soil, the tiny silicon particles contained in plant cells. The shapes of plant rocks of different plant species are different, including flake, spherical, cross, lens and ring. Plant rocks are preserved in the soil after plants die, so they can help experts judge the changes in plant species in the area. In addition, plant rocks are also used when studying ancient agriculture to determine when different plants were domesticated. "Plant rocks are tiny plant fossils," said Humberto Lombardo, a professor at the University of Bern, one of the authors of the research paper. "We can use them to identify plants that grew here in the past."
The analysis of the plant rock showed that the cassava in this area was grown about 10,350 years ago, the pumpkin-10250 years ago, and the corn-6850 years ago. Experts believe that local residents planted these plants around their homes. But it is not clear whether they can be called crops at all. Perhaps, they still retain some traces of their wild ancestors.
The new data also shows that there is a gap of 8,000 years from the beginning of garden-scale planting to the ownership of canals, fields, and full-scale agriculture that relies on domesticated species. In other parts of the world, this transition has occurred for about 1,000 years. Lombardo’s next research agenda is: Why did it take so long in the Amazon region?
The Amazon has had a huge impact on our modern diet. Peanuts, red peppers and some beans are the first plants grown here. After thousands of years of cultivation, their fertility and deliciousness have created the food we love today.
Lombardo said: “Archaeologists, geographers and biologists have believed for many years that the Southwest Amazon region may be the center of early plant domestication because of many important species such as cassava, pumpkin, peanuts, and some peppers and beans. The species is genetically very close to the wild plants that live here." "However, until this recent study, scientists did not excavate in this area that may record that these globally important crops were domesticated before Columbus discovered the American continent. Ancient ruins.”
Sara Ediot, an environmental archaeologist at Bournemouth University, commented on the research paper: “In the past, it was thought that humans had minimal impact on the Amazon region, but research results such as this one show that human activities The characteristics of landscape changes are extensive."
Capriles believes that they can estimate the diet of the first Amazon farmers based on the plant rocks they found.
This discovery made the southwestern Amazon region the fifth region in the world to invent agriculture, rather than introducing agriculture from other places. The other four are China, Fertile Crescent, Southwest Mexico, and the Andes.
