Scientists set for ocean crisis debate 150 years after ‘extraordinary’ expedition

Seascapes were little understood before the expedition, which has provided a baseline for looking at the state of our seas today. Photograph: Damocean/Getty Images

In a few days, several hundred researchers will gather in the UK to debate the crises facing the oceans – and to pay tribute to the expedition that first opened them up to scientific scrutiny.

Exactly 150 years ago, the Challenger expedition began a transformation in our understanding of the seas. It revealed the existence of myriad forms of life at every depth and showed the ocean floor was not a featureless plain, as then thought, but was peppered with mountain ranges and deep trenches.