Nicola Storelli and Daniele Zanzi: Scientists are obsessed with this lake

Scientists are obsessed with this lake

In the millions of years since oxygen began saturating Earth’s oceans and atmosphere, most organisms have evolved to rely on this gas. However, there are some places where oxygen-averse microorganisms like those from Earth’s earliest days have re-emerged. And one such place is hidden high in the Swiss Alp’s Piora Valley. Nicola Storelli and Daniele Zanzi dive into the depths of Lake Cadagno. [Directed by Ivana Volda, Thomas Johnson Volda, narrated by Addison Anderson, music by Stephen LaRosa].

Lake Cadagno hides an ancient secret beneath its surface—two unmixed layers of water that replicate the chemical divide from billions of years ago. While the upper layer teems with fish, just 13 meters below lies a toxic, oxygen-free world filled with microbes like those that existed before oxygen dominated the planet. This unique setting lets scientists observe rare anaerobic life and uncover clues to early evolution, including how simple swimming behaviors may have first evolved. The lake’s striking ecology offers a living laboratory to study Earth’s distant past.