Earth's 4.5 billion year geological history is full of death and rebirth, mass extinctions and explosions of biodiversity, with different periods often marked by cataclysmic changes that radically reshaped environments and climates. Whether it was major ice ages or meteor impacts, these changes encompass everything from the shape of our continents to the composition of our oceans.
One of the biggest ongoing debates in science is whether or not human activity, such as burning fossil fuels and triggering climate change, has had enough of an impact to create what can be considered a new geologic era. After all, scientists repeatedly remind us that our rapidly-heating planet is sending us into "uncharted territory" as we regularly break heat records and seem to be triggering a mass extinction some have called a "biological holocaust."
