Around five percent of all the people who have ever lived are still alive. That's an astoundingly high proportion given that modern homo sapiens have been around for upwards of 150,000 years, and it speaks to just how steeply the world's population has increased within living memory.
This increase, along with the technological advances that made it possible, have fundamentally transformed our planet in a way that has obviously taken an enormous toll. We've cleared away habitats to make way for our agriculture, practically emptied the sea of fish, and begun to change our climate, but the pace of all this has been just slow enough for each new generation to grow up thinking it's always been this way, that our use of natural resources is normal so we can go on like this forever. But we clearly can't. The reality we are now living with, and have apparently been living with for the last century, is that the Earth is experiencing a mass extinction event on a scale not unlike the one that killed off the non-avian dinosaurs. Over the last century, vertebrate species have been disappearing at a pace that is conservatively estimated to be 114 times the background rate.
