As Threats to Biodiversity Grow, Can We Save World’s Species?

[Dead_Parrot]

A million species could face extinction due to human encroachment and climate change.

Throughout much of the Pleistocene era, which began 2.5 million years ago, many of the world’s large mammals survived periods of glaciation and deglaciation by moving across a landscape devoid of humans. Then as the Pleistocene drew to a close at the end of the last Ice Age — some 20,000 to 12,000 years ago — creatures such as the wooly mammoth had to confront not only shrinking habitat caused by climate change. They also faced thousands of humans with stone-tipped weapons, a one-two punch that led to the extinction of dozens of so-called megafauna species, including the wooly mammoth, across Eurasia and North and South America.

Now, with 7 billion people on the planet — heading to 10 billion — and with greenhouse gas emissions threatening more rapid temperature rises than the warming that brought the last Ice Age to an end, the many millions of living things on Earth face an unprecedented squeeze. Is a wave of extinctions possible, and if so, what can we do about it?

The late climate scientist and biologist Stephen Schneider once described this confluence of events — species struggling to adapt to rapid warming in a world heavily modified by human action — as a “no-brainer for an extinction spasm.” My colleagues Barry Brook and Anthony Barnosky recently put it this way, “We are witnessing a similar collision of human impacts and climatic changes that caused so many large animal extinctions toward the end of the Pleistocene. But today, given the greater magnitude of both climate change and other human pressures, the show promises to be a wide-screen technicolor version of the (by comparison) black-and-white letterbox drama that played out the first time around.”

The magnitude of the threat was first quantified in a 2004 Nature study, “Extinction Risk from Climate Change.” This paper suggested that in six diverse regions, 15 to 37 percent of species could be at risk of extinction. If those six regions were typical of the global risk, the study’s authors later calculated, more than a million terrestrial and marine species could face extinction due to human encroachment and climate change — assuming conservatively that 10 million species exist in the world. Headlines around the world trumpeted the 1 million figure.

More: http://e360.yale.edu/feature/as_threats_to_biodiversity_grow_can_we_save_worlds_species/2518/

[NickB79]

1. No. Next question? nt

[stuntcat]

2. but everyone simply HAS to make copies of themselves!

if you don't believe me ask my mother-in-law! She told me she wishes I was dead because I won't make additional human #7,000,000,192!

Sorry.. mass-extinction causes me to vent.