biosphere

The study, published in the Proceedings of the National Academy of Sciences, offers new understanding of Earth's earliest biosphere.

"By understanding the limits that apply to all living systems, we can better predict how cells, ecosystems, and even entire biospheres respond to changing environments."

By demonstrating how urea could form naturally under Archean conditions and showing that it acts as both a nutrient and an inhibitor, the researchers revealed how subtle chemical balances shaped Earth's early biosphere.

A planet with ten percent carbon dioxide -- if located farther from its sun or orbiting a dimmer, younger star -- could support a biosphere for up to 4.2 billion years.

As well as the music, climate activist Greta Thunberg also made a surprise appearance, telling festival goers the earth's biosphere is "not just changing, it is breaking down".