Crisis: Extinctions

Even if we knew precise details of Earth's core, we would not be able to predict a catastrophic flip in the polarity of its magnetic field more than a decade or two ahead.

Originally published in Yale Environment 360, Sonia Shah writes that in the past dozen years, three new diseases have decimated populations of amphibians, honeybees, and -- most recently -- bats. Increasingly, scientists suspect that low-level exposure to pesticides could be contributing to this rash of epidemics.

Fossil fuels have a new crime to live down. A frenzy of hydrocarbon burning at the end of the Permian period may have led to the most devastating mass extinction Earth has ever seen, as explosive encounters between magma and coal released more carbon dioxide in the course of a few years than in all of human history.

The idea that bees are disappearing for reasons unknown has embedded itself in the public consciousness. It is also a great story that taps into the anxieties of our age. But is it true? We think not, at least not yet.

The film examines the evidence for this confusing tangle of theories, but it ultimately settles one another cause altogether: pesticides... These pesticides aren't intended to kill bees. But, according to filmmakers, around the time bee deaths started being reported, a new type of neonicotinoid-based "systemic" pesticide produced by Bayer Crop Science and other agrochemical companies was deployed by farmers

World Environment Day on Friday sees the worldwide release of a movie billed by producers as “the greatest green event ever,” a high-budget documentary from Yann Arthus-Bertrand about saving the planet.

Scientists around the world are beginning work on what they hope will be a comprehensive online directory of all life on Earth, built in large part on the efforts of amateur observers.

The builders of the ancient Mayan temples at Tikal in Guatemala switched to inferior wood a few decades before they suddenly abandoned the city in the 9th century AD. The shift is the strongest evidence yet that Mayan civilisation collapsed because they ran out of resources, rather than, say, disease or warfare.

When I was invited to give this speech, I was asked if I could give a simple short talk that was “direct, naked, taut, honest, passionate, lean, shivering, startling, and graceful.” Boy, no pressure there.

There is little doubt left in the minds of professional biologists that Earth is currently faced with a mounting loss of species that threatens to rival the five great mass extinctions of the geological past, the most devasting being the Third major Extinction (c. 245 mya), the Permian, where 54% of the planet's species families lost. As long ago as 1993, Harvard biologist E.O. Wilson estimated that Earth is currently losing something on the order of 30,000 species per year -- which breaks down to the even more daunting statistic of some three species per hour. Some biologists have begun to feel that this biodiversity crisis -- this "Sixth Extinction" -- is even more severe, and more imminent, than Wilson had supposed.