A new study by researchers from three U.S. universities echoes an earlier report out of Duke University indicating that earth is in what appears to be the beginning of its sixth mass extinction – the first in some 65 million years. Large animals face the highest rate of decline, and their losses could affect other species, including us.
Studies have shown that when large animals are removed from an ecosystem, the number of rodents in the area doubles. Rodents harbor an abundance of disease-carrying pathogens, so as their numbers increase, so does the risk of disease transmission to humans. This situation can be found anywhere where human density is high.
We talked about the trouble facing vertebrates yesterday, but invertebrates aren’t faring well either. During the past 35 years, human population has doubled, while invertebrate populations have decreased by 45%. Insects play a critical role in human survival, pollinating roughly 75% of the world’s food crops. The destruction of ecosystems could lead to the loss of ecosystem services such as pollination within just three human generations. And researchers fear that 75% of the species we know today could be lost within two generations.
Scientists say that immediately reducing the rates of habitat loss, habitat degradation for economic gain, and climate change would help. But they argue that raising awareness of the mass extinction and its fallout for all life forms – including humans – should be most effective in driving change.
After all, the time we have to avoid dramatic consequences is rapidly running out.
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Web Links
Stanford biologist warns of early stages of Earth’s 6th mass extinction event
Earth Has Entered First ‘Mass Extinction’ Since Dinosaurs, Study Warns
Photo, posted January 2, 2010, courtesy of Pablo via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio.