Sixth Mass Extinction

Would it surprise you to learn a sixth mass extinction is underway? How about Earth’s species disappearing 15-100 times faster than the normal rate between previous mass extinctions? Knowing, not since dinosaur’s swan song has Earth witnessed such rapid eradication of species?

Image credit: Stanford University

A study published June 19, 2015 in the Journal Science Advances demands a little pondering. Scientists from Berkeley, Princeton, Stanford, University of Florida, and Universidad Autonoma de Mexico called for immediate action to conserve threatened species, warning the window of opportunity is closing fast.

Gerardo Ceballos of the Universidad Autónoma de México is the study’s lead author. Ceballos said:

If it is allowed to continue, life would take many millions of years to recover, and our species itself would likely disappear early on.

There is general agreement among scientists that extinction rates have reached levels unparalleled since the dinosaurs died out 66 million years ago. However, some have challenged the theory, believing earlier estimates rested on assumptions that overestimated the crisis.

Using fossil records and extinction counts from a range of records, the researchers compared a highly conservative estimate of current extinctions with a background rate estimate twice as high as those widely used in previous analyses.

The researchers wrote:

We emphasize that our calculations very likely underestimate the severity of the extinction crisis, because our aim was to place a realistic lower bound on humanity’s impact on biodiversity.

Study co-author Paul Ehrlich is the Bing Professor of Population Studies in biology and a senior fellow at the Stanford Woods Institute for the Environment. Ehrlich said:

[The study] shows without any significant doubt that we are now entering the sixth great mass extinction event.