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Biodiversity
Birds and animals, grass and trees, insects and fishˇKall are species of our diverse planet. Most people are familiar with only about 3% of all species. A single species often consists of a number of varieties. Varieties of rice, for example, both wild and domesticated in different geographical areas, amount to 140,000. Biodiversity, or the diversity of organisms, has given rise to a complicated ecological network, in which different species depend on and cast influence on one another. For humans, bio-diversity has ensured the sustainability of our food supply and livelihood. What we eat, wear and use are mostly acquired from the innumerable species on our planet.
However, human activities have resulted in decreasing biodiversity. For example, some 75% of agricultural crop varieties have disappeared over the past century. It is estimated that we are losing 50 to 100 species every day. Commercial mono-cropping on a massive scale is one of the causes of the discontinuance of agricultural crop species and the consequent weakening of our planet's biodiversity. Other activities threatening biodiversity include massive deforestation and excessive land development.
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