GRE写作Issue部分精品素材分享之生活多样性的定义

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生物多样性定义的争议

The 1992 United Nations Earth Summit in Rio de Janeiro defined “biodiversity” as “the variability

among living organisms from all sources, including „inter alia‟, terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems”. This is, in fact, the closest thing to a single legally accepted definition of biodiversity, since it is the definition adopted by the United Nations Convention on Biological Diversity.

If the gene is the fundamental unit of natural selection, according to E. O. Wilson, the real biodiversity is genetic diversity. For geneticists, biodiversity is the diversity of genes and organisms. They study processes such as mutations, gene exchanges, and genome dynamics that occur at the DNA level and generate evolution.

For ecologists, biodiversity is also the diversity of durable interactions among species. It not only applies to species, but also to their immediate environment (biotope) and their larger ecoregion. In each ecosystem, living organisms are part of a whole, interacting with not only other organisms, but also with the air, water, and soil that surround them.

某些物种具有多样性原因

The rich diversity of unique species across many parts of the world exist only because they are separated by barriers, particularly large rivers, seas, oceans, mountains and deserts from other species of other land masses, particularly the highly fecund, ultra-competitive, generalist “super-species”. These are barriers that could never be crossed by natural processes, except for many millions of years in the future through continental drift. However, humans have invented ships and airplanes, and now have the power to bring into contact species that never have met in their evolutionary history, and on a time scale of days, unlike the centuries that historically have accompanied major animal migrations.

对生物多样性保护的资助

The field of biodiversity research (inevitably) suffers from natural human egocentric “myopic” cognitive biases. It has often been criticized for being overly defined by the personal interests of the founders (i.e. terrestrial mammals) giving a narrow focus, rather than extending to other areas where it could be useful. This is termed the founder effect by Norse and Irish, (1996). (This was a play on words: the founder effect in ecology typically refers to the genetic outcome when a small population establishes an isolated breeding group.) France and Rigg reviewed the biodiversity literature in 1998 and found that there was a significant lack of papers studying marine ecosystems, leading them to dub marine biodiversity research the sleeping hydra. More work has been carried out for accessible, diverse coastal systems such as coral reefs than for inaccessible, species-poor deep sea areas.

It has been easier to mobilize public opinion and national legislation for the terrestrial realm, which has higher visibility and falls within countries‟ territorial boundaries. Marine conservation involves having to pioneer new and international mechanisms of protection as well as solving methodological problems in marine biology relating to marine ecosystem classification and data-gathering on some of the earth‟s most difficult species to access and monitor.

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