Beneath the seawater in Japan's Beppu Bay lie layers of seemingly unremarkable sediment and sludge that tell the story of how humans have fundamentally altered the world around them.
The site is among those being considered for designation as a "golden spike," a location that offers evidence of a new geological epoch defined by our species: the Anthropocene.
The path to delineate the new era has been long and controversial, with scientists wrangling for years over whether the Holocene epoch that began 11,700 years ago has really been replaced by a new period defined by human impact on the Earth.