Researchers have uncovered the scale of two ancient cities buried high in the mountains of Uzbekistan. The cities were thought to be there, but their extent was unknown, so the team used drone-mounted LiDAR equipment to reveal what was hidden beneath the ground. The survey surprised researchers by showing one of the cities was six times bigger than expected. The two cities, called Tashbulak and Tugunbulak, were nestled in the heart of Central Asia’s medieval Silk Road, suggesting that highland areas played an important role in trade of the era.

Research Article: Frachetti et al.

Video: Uncovering a lost mountain metropolis

How children's’ movements resemble water vapour, and why coastal waters may be a lot dirtier than we thought.

Research Highlight: Kids in the classroom flow like water vapour

Research Highlight: Sewage lurks in coastal waters — often unnoticed by widely used test

A team at Google Deepmind has demonstrated a way to add a digital watermark to AI-generated text that can be detected by computers. As AI-generated content becomes more pervasive, there are fears that it will be impossible to tell it apart from content made by humans. To tackle this, the new method subtly biases the word choices made by a Large Language Model in a statistically detectable pattern. Despite the changes to word choice, a test of 20 million live chat interactions revealed that users did not notice a drop in quality compared to unwatermarked text.

Research Article: Dathathri et al.

News: DeepMind deploys invisible ‘watermark’ on AI-written text

What one researcher found after repeatedly scanning her own brain to see how it responded to birth-control pills, and how high-altitude tree planting could offer refuge to an imperilled butterfly species.

Nature: How does the brain react to birth control? A researcher scanned herself 75 times to find out

Nature: Mexican forest ‘relocated’ in attempt to save iconic monarch butterflies

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