Recently, scientists published 3 studies that analyzed ancient DNA samples from skeletons of what they believe are the first farmers in the world. These samples were found in the Fertile Crescent region in Western Asia and the research discovered that farming was not used by a homogeneous group, but by a diverse group of farmers that came from different places. Whether if agriculture was invented several times or spread is still a mystery, but archaeologists have some theories, based on the new studies.

Science posted Friday one of the papers that consider the origin of the first farmers. The other 2 studies were published 2 months ago on the bioRxiv preprint server for biology. All 3 studies came to the conclusion that the first people that develop agriculture were from different locations from the Fertile Crescent region. From this geographical area, it is believed that farming spread to the surrounding regions and later to Europe, southern Asia, and parts of Arabia and Africa, says the report.

Fertile Crescent Map. Credit: Thing Link

The Fertile Crescent arcs from the Persian Gulf to Turkey and south Egypt. This witnessed how humans started the firsts plant cultivations and animal herding, which happened 10 thousand to 12 thousand years ago. Early evidence of these activities has been found in excavations in Jordan, Iraq, and Turkey and it shows that they practice agriculture and goat domestications roughly at the same time, Science reports.

Joachim Burger of the Johannes Gutenberg University of Mainz in Germany led the team of scientist that sought the origins of the first farmers in history. The study, published in Science, analyzed the nuclear DNA through new methods that extract it from the petrous bone of the ear the sample, which is rich in DNA. The research includes the efforts of Marjan Mashkour and Fereidoun Biglari of the National Museum of Iran in Tehran.

According to the paper, the scientists sequenced the complete genomes of 4 goat herders skeletons that were found in the Zagros Mountains on the border of modern-day Iran and Iraq. A male from Wezmeh Cave, who was 9 thousand years old, was one of the archeological samples. The other 3 were individuals from Tepe Abdul Hosein and were badly preserved. They are 10 thousand years old and are among the oldest Neolithic human remains in the world.

The results from tests of isotopes in the teeth of all 4 agriculturists proved that their diets were rich in grains, which is related to a farmer’s way of life.

Hellenthal found that Iranian DNA is dramatically distinct from western Anatolian farmers. Science says that the 2 groups must have descended from completely different ancestors that separated 46 thousand to 77 thousands years ago.

The study published in Science found that the first Zagros Mountain farmers are part Pakistanis genetic. Afghans and Zoroastrians genetics can be traced to the first agriculturists of the world.

Credit: Science

Another 2 studies also sought answers in the Fertile Crescent area. First farmers were indeed a diverse group.

David Reich from Harvard University also led a similar research that studied ancient DNA from 44 Middle Easterners who lived 14 thousand to 3,400 years ago. The paper published on bioRxiv includes Zagros farmers, Natufian hunters, who also were gatherers, in Israel, and Bronze Age pastoralists in the Eurasian steppe. Reich and his team compared their DNA with 2,864 ancient living people from different parts of the globe.

Science explains that this study sequenced 1.2 million nucleotides from across each genome and found that early farmers of Israel and Jordan were genetically different from the remains found in the Zagros Mountains. And when the team compared the DNA of those skeletons from Israel and Jordan with the ones found in western Anatolians, they discovered they were distinct as well. Anatolians were the people that spread agriculture to Europe.

The third research studies the complete genome of a woman from Ganj Dareh, located in the Zagros Mountains. The remains were 10 thousand years old and the DNA results were similar to the ones reported in the first 2 papers. The study was also posted on bioRxiv.

None of the studies could determine if agriculture was invented more than once or if it was shared and spread around the globe.

The hot climate of the Middle East destroys DNA and other archeological evidence. This represents an obstacle when trying to understand the origins of agriculture and other activities related to the first steps of the human race.

But the fact that it is a difficult task has not stopped scientists from trying to understand if farming was a process that was invented several times of it was the product of migration and sharing knowledge.

Science says that Burger thinks that agriculture is the result of people spreading this activity, which started in the movement of individuals. The scientist proposes that agriculture was an idea that spread and reached the borders of Europe. He added that this spread was a revolution started by people who were incredibly diverse.

But some archaeologists realized that early farmers used different tools and plants in various regions. Science reports that Roger Matthews of the University of Reading in the United Kingdom supports the idea of multiple origins. He believes that genetic and archaeological evidence suggest that agriculture was practiced differently in the distant ends of the Fertile Crescent, and eventually were unified that then spread to other regions.

Source: Science