Though most of the world's surface is covered by water, since the Earth is so large relative to human horizons, there doesn't appear to be a shortage of land. However, when one begins to think of land in terms of a human resource, i.e., a producer of food, a provider of wood, an expanse for passage, one realizes that many portions are either too lacking in nutrients, too high in elevation, too prone to flooding, or too cold or ice-ridden for extensive use. Furthermore, habitable lands are becoming less abundant due to desertification (the expansion of deserts due to the misuse of land), agricultural expansions and rising sea levels. Since humans aren't the only species that need land, it isn't surprising that this resource is becoming limited for other forms of life too. In part as a result of this added stress on living things, we are also witnessing extinctions of grand proportions-at a rate of many thousands species per year. Since these losses are largely due to human actions, such as deforestation and non-native species introduction, many are beginning to pay attention to how we use and protect land. Recent ecological research has also recently provided a message of hope concerning the future well-being of life on this planet.
In the world today, scientists estimate that the Earth is losing at least 1 percent of species every ten years, and the percentage loss may be close to 5 percent. Even if only the lower rate persists, the Earth will have lost near half of its biological diversity by 2070. Can this be possible? Many esteemed scientists think so. While the future appears bleak, several recent insights tell us that we have the potential to significantly reduce what amounts to a biotic holocaust, one not witnessed on Earth for over 60,000,000 years. While there are hopeful signs in the area of human activities (such as increased acreage of nature preserves and national parks), the hope of which I speak of here stems from specific characteristics of the other forms of life which may enable us to mutually coexist in the long term.
The Earth's organisms are wonderfully varied in size, shape, function, behavior, and genetic code. One only need to consider that there are ~ 15,000 species of butterflies and ~50,000 species of mushrooms worldwide to begin to fathom the immensity of variety that this planet has. Yet, as different as the species come, the bulk of living things are also similar in a couple of very important ways. Most living things live in relatively small regions and do not travel far from where they or their parents were born. In fact, recent biological and ecological work has determined that most land species are very particular about where they live. As opposed to humans whose choice of home is largely driven by economic and political forces (mobility driven by availability of wealth or forced relocation), flora and fauna find themselves in locations for which they are adapted. We now know that many species of insects and plants have a very restricted range in which they found. Very few organisms are ubiquitous like we are. It goes without saying that you aren't going to find a Great Blue Heron or a Grizzly visiting Antarctica or climbing Mt. Everest; yet you might find the snow bear (recently discovered and previously known as the Abominable Snowman) doing the latter. Recognizing that most living things are rather localized during their lifetimes has profound implications, both hopeful and cautious. On the one hand, it suggests that we can learn a lot about species by parking our scientific minds in specific locations. On the other hand, it means that if we destroy even small areas of the globe we are likely causing great and even irreversible destruction to the species that are found there.
We have also determined that there are specific locations on our planet where a disproportionate number of species live. For our species, Asia serves as the homeland for most. In fact more than 60 percent...
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