Experts have found a group of lost cities in the Amazon rainforest. The cities were home to at least 10,000 farmers around 2,000 years ago.

Recent mapping using laser (激光) technology revealed those places to be part of a group of settlements and connecting roads. The settlements are in the forested areas near the Andes mountains.

“It was a lost valley of cities,” said Rostain, who directs research at France’s National Center for Scientific Research. “It’s unbelievable,” he added. The Upano people lived in the settlements between around 500 BC and 300 to 600 AD. That was around the same time period as the Roman Empire in Europe, the researchers found.

Ancient people built on over 6,000 earthen mounds (堆) in an area surrounded by agricultural fields with drainage (排水) canals. The largest roads were 10 meters wide and went for 10 to 20 kilometers.

While it is difficult to determine populations, the area was home to at least 10,000 people, and possibly about 15,000 or 30,000 at its highest point. That is comparable to the possible population of London, then Britain’s largest city.

It would have required a complex system of organized labor to build the roads and thousands of earthen mounds. The Incas and Mayans built with stone, but people in Amazonia didn’t usually have stone available to build — they built with mud.

The Amazon is often thought of as a wild area with only small groups of people. But recent discoveries have verified that the past was really more complex.

Scientists have recently also found evidence of complex rainforest societies that came before European contact elsewhere in the Amazon, including in Bolivia and Brazil.

“There’s always been an unbelievable diversity of people and settlements in the Amazon, not only one way to live,” said experts. “We’re just learning more about them.”

Joyce Loaiza lives alone in a community for older people in the American state of Florida. When she is home, the retired office worker often talks with a friendly female voice that asks about her day.

A few kilometers away, the same voice helps 83-year-old Deanna Dezern. In New York state, it plays games and music for 92-year-old Marie Broadbent. And in Washington state, it helps 83-year-old Jan Worrell make new friends.

These women are some of the first in the United States to receive the robot ElliQ made by Intuition Robotics. The company says it is the only device using artificial intelligence (AI) to help older Americans from loneliness.

The device looks like a small table light and it has an eyeless, mouthless head that lights up and turns. It remembers each user’s interests and their talks, helping create a special experience with new discussions. They can be as deep as the meaning of life or as light as a small joke.

ElliQ also plays music and provides creative or spiritual sayings. On a video screen that comes with it, it will show different cities and places of interest. The device leads exercises, asks about the owner’s health, and gives reminders to take medicines and drink water. It can also support video calls and contact family, friends, or doctors in an emergency.

Intuition Robotics says none of the private conversations are heard by the company, with the information only staying on each owner's device.

A robot could fill the space of a friend by adapting to each person and their interests. The average user communicates with ElliQ more than 30 times a day and more than 90 percent report lower levels of loneliness.

The robots are mostly sent out by government departments. But they can also be bought individually for $600 a year plus $250 to set it up.