Extinctions
Our earth has experienced five mass extinctions caused by natural catastrophes in which over 75% of all plant and animal species disappeared.
Human Driven Extinction
Today we are facing a sixth mass extinction driven by our own species. We are new to this planet; Homo sapiens evolved just 100,000 years ago on a planet that has had vibrant life forms for half a billion years. Yet, we are having a disproportionate impact on the planet’s biodiversity.
Extinction Drivers
Our rapid population growth—we grew five times in the last one hundred years—is pushing animals from their habitats, propelling overkill of many species, increasing chemical pollutants, and spreading invasive species.
Climate Change
But most frightening for the animals of this planet may be the swift climate change we have initiated through increased release of carbon dioxide, a change that is occurring much faster than animals can evolve and adapt.
Pre-industrialization carbon dioxide levels were 270 ppm; today they are 390 ppm and predicted to to between 540 and 970 ppm by 2100, unless we change our ways. Tellingly, the last five extinction were associated with both high levels carbon dioxide and temperatures.
The First Five Mass Extinctions
The three waves of the Sixth Extinction: