Enter the Anthropocene: Humans’ impact on the Earth has defined a new epoch, experts say. An official expert group presented their recommendation for a new geological epoch — the Anthropocene — to the International Geological Congress in Cape Town yesterday, The Guardian reports.

As Damian Carrington reports for The Guardian, “The new epoch should begin about 1950, the experts said, and was likely to be defined by the radioactive elements dispersed across the planet by nuclear bomb tests, although an array of other signals, including plastic pollution, soot from power stations, concrete, and even the bones left by the global proliferation of the domestic chicken were now under consideration.”

Our current epoch, the Holocene, has been 12,000 years human development under stable climate since the last ice age. The experts argue that the dramatic acceleration of carbon dioxide emissions and sea level rise, as well as the mass extinction of species and the transformation of land from deforestation and development, have brought an end to that epoch. As Carrington puts it, “The Earth is so profoundly changed that the Holocene must give way to the Anthropocene.”