Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A complex agricultural society in Uruguay’s La Plata basin, 4,800-4,200 years ago

02.12.2004


A complex farming society developed in Uruguay around 4,800 to 4,200 years ago, much earlier that previously thought, Iriarte and his colleagues report in this week’s Nature (December 2). Researchers had assumed that the large rivers system called the La Plata Basin was inhabited by simple groups of hunters and gatherers for much of the pre-Hispanic era.



Iriarte and coauthors excavated an extensive mound complex, called Los Ajos, in the wetlands of southeastern Uruguay. They found evidence of a circular community of households arranged around a central public plaza. Paleobotanical analyses of preserved starch grains and phytoliths –tiny plant fossils- show that Los Ajos’ farmers adopted the earliest cultivars known in southern South America, including maize, squash, beans and tubers.

Over time, around 3,000 years ago, the mound complex architectural plan of Los Ajos exhibited sophisticated levels of engineering, planning, and cooperation revealing an earlier, new, and independent architectural tradition previously unknown from this region of southern South America. The formal and compact layout of the central part of the site (Inner Precinct) consists of seven imposing platform mounds surrounding a central plaza area.


Iriarte extracted a sediment core from nearby wetlands to reconstruct what the environment was like when this farming society arose. Combined analyses of preserved pollen and phytoliths indicated that, as in other regions of the world, the mid-Holocene was characterized by significant climatic and ecological changes associated with important cultural transformations. During this period, around 4,500 years ago, the climate was much drier than it is today and "Wetlands became biotic magnets for human habitation providing an abundant, reliable, and a resource-rich supply of foods and water. Furthermore, wetland margins offered an ideal place for the experimentation, adoption, and intensification of agriculture encouraging the Los Ajos’ community to engage into horticulture", explains Iriarte, currently a post-doctoral fellow at the Smithsonian Tropical Research Institute (STRI) in Panama.

At Los Ajos, cultural artifacts are spread out over 12 ha. suggesting the presence of a large resident population. Moreover, as Iriarte indicates "Los Ajos is far from a lonely isolated community in southeastern Uruguay. In the ten square kilometers surrounding Los Ajos alone there are ten other large and spatially complex mound sites. These were thriving societies that probably were integrated into regional networks of towns and villages". Iriarte believes that "this region was a locus of early population concentration in lowland South America."

José Iriarte | EurekAlert!
Further information:
http://www.si.edu

More articles from Agricultural and Forestry Science:

nachricht Energy crop production on conservation lands may not boost greenhouse gases
13.03.2017 | Penn State

nachricht How nature creates forest diversity
07.03.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>