The Free Press, Mankato, MN

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April 17, 2009

Biodiversity decline a threat

Earth Day is April 22 and each year since 1976 I have written a special column to draw attention to this event. These columns are painful to write because the overall health of planet Earth is declining, but I am naive enough to think that discussion of the problems just might spur some of us to help with the recovery process.

Today, I am going to focus just on biodiversity, explain why it is essential, and discuss some ways we as individuals can help preserve it.

In a new book “How Human Health Depends on Biodiversity,” the authors drive home the point that humans need biodiversity. We need biodiversity for food, fiber, shelter, medicines, recycling of waste and a whole host of invaluable goods and services. In short, biodiversity makes the Earth habitable.

Yet, diversity is declining in practically every taxonomic category that has been analyzed. David Mindell writing in Science recently reported those threatened include 12 percent of all bird species, 20 percent of all mammals, a third of our fellow primates, 25 percent of the conifers and 52 percent of the cycads. Others have reported that one-third of the amphibian, fish and reptile species are threatened. Here in the U.S., The New York Times recently reported that a third of bird species are declining. In Hawaii, most of the bird species are threatened.

The environmental organization Garden Organic reports that 95 percent of the vegetables we eat come from just 20 species of plants, but 98 percent of vegetable varieties have disappeared during the last 100 years. Similar horror stories exist for fruit varieties.

Harvard biologist E. O. Wilson has argued that “every scrap of biological diversity is priceless, to be learned and cherished, never to be surrendered without a struggle.” Wilson attributes the loss of biodiversity to five forces summarized in the acronym HIPPO – habitat loss, invasive species, pollution, population growth and overexploitation of species for consumption.

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