Over the course of the planet’s history, Earth has undergone five cataclysmic events that have obliterated life, killing most species. Scientists claim that Earth is on the brink of a sixth mass extinction. Only this time, geology is not to blame; rather, humans are the culprit.
Unlike previous extinctions, this sixth mass extinction is unique because of four characteristics:
1. Global homogenization of flora and fauna. In other words, because of human intervention, fauna and flora have begun to dissipate around the world, enabling humans across the planet to enjoy the same things (such as tomatoes and horses), while simultaneously ruining ecological communities and leading to extinction.
2. Humans on top. Uniquely, humans are the top predator across the whole earth, and as a result, they use 25 to 40 percent of the planet’s primary production for their own purposes. No other species has dominated in this way.
3. Humans in charge of evolution. Humans are actively invested in directing evolution, due to the domestication of animals and the cultivation of crops as well as genome manipulation and conservation efforts.
4. Development of technosphere. The technosphere is a term scientists have coined to refer to the combination of humanity and technology, which has created, in a sense, a new sphere that is wholly foreign to the planet.