Big Question for 2012: What Animals Could Go Extinct?
- Analysis by Jennifer Viegas Thu Dec 15, 2011 06:48 PM ET
(The Golden Toad was last seen on May 15, 1989, and is presumed to be extinct.)
The world's biodiversity is declining at an unprecedented rate, according to the most recent Global Species Assessment and many other related studies. As a result, more extinctions are predicted for 2012.
While extinctions have been occurring on our planet since close to the beginning of life on Earth, we are now essentially living through an experiment with no predictable outcome. The prior five major mass extinctions, for the most part, happened over relatively long periods of geological time.
WIDE ANGLE: BIG QUESTIONS FOR 2012
In contrast, it's believed that some 10,000 species have gone extinct in just the past 100 years, with the evolution of new species not keeping up with the losses. Human activities, such as habitat encroachment, hunting, pollution and more are largely to blame.
According to Conservation International...
- At least 15 species have gone extinct over the past few decades. The real extinction figure is believed to be much higher, however, due to the conservative approach used in such listings;
- Thousands of animal, plant and lichen species are now considered at risk of extinction;
- One in three amphibians (32%) and almost half (42%) of turtles and tortoises are now known to be threatened with extinction, along with one in eight birds (12%) and one in four mammals (23%);
- There are major gaps in our knowledge of threatened species, and many species-rich groups have been poorly assessed;
- The numbers of threatened species are increasing across almost all major taxonomic groups;
- Continental species extinctions have become as common as extinctions on islands, which are typically more ecologically fragile, and
- Current extinction rates are at least one hundred to a thousand times higher than background, or "natural" rates.
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