People sometimes say we need to be really almost on a wartime footing if you want to change. Our whole economy is based on burning fossil fuels, which is taking CO2 out of the ground and putting it up into the air.

People sometimes say we need to be really almost on a wartime footing if you want to change. Our whole economy is based on burning fossil fuels, which is taking CO2 out of the ground and putting it up into the air.

If you're a conservation biologist in many fields, you're seeing your study subject disappear. People are in the position where they're chronicling radical decline, and that is not a position that conservation biologists want to be in.

As best as can be determined, the world is now warmer than it has been at any point in the last two millennia, and, if current trends continue, by the end of the century it will likely be hotter than at any point in the last two million years.

Some of these species that are now no longer with us were killed off by a fungal disease that was moved around the planet by people.

We can't say that when x happens we get a mass extinction. To the extent we understand mass extinction, one has been caused by glaciation event, one has been caused by a massive climate change, and one has been caused by an asteroid. These events turn out to have no precedent.

No matter what Donald Trump says, it's clear that global warming is rapidly changing conditions on our planet.