新的证据表明人类在12000年前使用过烟草

Scientists have discovered new evidence that humans used tobacco at least 12,000 years ago.

The evidence was found by an archaeological team at a site in a desert in the western American state of Utah. The dig centered on an ancient fireplace built by a group of hunter-gatherers. The scientists found four burned seeds of a wild tobacco plant along with other objects.

The discovery is reported to be the oldest evidence of tobacco use. Among other objects found at the Utah site were stone tools and bird bones. The scientists believe the birds had been food for the community.

Until now, the earliest documented use of tobacco was from a finding of the drug nicotine inside an ancient pipe in Alabama, a southern state. The pipe, used for smoking, dated back 3,300 years ago.

The new find was reported in a study that appeared in the scientific publication Nature Human Behavior.

The researchers believe the group may have smoked the tobacco or possibly put pieces of the plant in their mouths. They think the users were seeking the pleasant effects nicotine produces in the body.

The first known tobacco use is linked to native communities in North and South America. Its use spread worldwide following the arrival of Europeans more than five centuries ago.

Today, tobacco represents a worldwide public health crisis. The World Health Organization (WHO) estimates there are 1.3 billion tobacco users across the world. The WHO blames tobacco use for more than 8 million deaths each year.

Daron Duke is an archaeologist with the Far Western Anthropological Research Group in Nevada. He was the lead writer of the study. Duke told Reuters news agency that worldwide, he considers tobacco "the king of intoxicant plants."

"And now we can directly trace its cultural roots to the Ice Age," he added.

The seeds belonged to a wild kind of desert tobacco called Nicotiana attenuata, which still grows in the area. "This species was never domesticated but is used by indigenous people in the (area) to this day," Duke said.

Scientists say the area was likely marshland at the time the fireplace was used. The area had a cool climate during the Ice Age period.

The remains of the fire were found in areas where wind has been blowing surface material away since the marshland fully dried up about 9,500 years ago.

"We know very little about their culture," Duke said of the hunter-gatherers. The most interesting part of the find, he said, is the "social window it gives to a simple activity in an undocumented past."

"My imagination runs wild," he added.

Duke said tobacco domestication happened thousands of years later elsewhere on the continent, for example in the Southwestern and Southeastern United States and in Mexico.

Some researchers have theorized that tobacco may have been the first plant domesticated in North America. They believe this happened because of the substance's sociocultural effects rather than for food purposes.

Duke said he thinks the find provides clear evidence that the hunter-gatherers were experienced growers of tobacco long before food requirements later drove investments in agriculture.

I'm Bryan Lynn.

Reuters and Nature reported on this story. Bryan Lynn adapted the reports for VOA Learning English. Cay Weaver was the editor.

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