Chris Baraniuk recently wrote a BBC article about how the Devonian extinction period some 360 milllion years ago. In this extinction, the largest animals lived in the oceans and a few animals and plants lived on land.
It has been recently theorized that the oceanic extinction of the Devonian period was caused by land plants that dug their roots deeply into the ground, creating more soil. This influx of soil ran into the oceans and caused a decrease in the amount of available dissolved oxygen. Without enough oxygen in the water, the animals were suffocated and a mass oceanic extinction occurred.
The Earth may go through natural fluctuations in temperature and natural life availability, however, let's not let humans be the main cause of the next extinction. Species are currently experiencing a rate of extinction at 100 times the natural rate, and humans are to blame.
It may not seem like much, but something as small as signing a petition against oil drilling in the Arctic is an important step in the direction of