We need biodiversity because lack of it could cause problems
By preserving biodiversity we could save money on the NHS and other public health services. The animals that play host to mosquitoes and ticks will go unchecked by predators if the predators are driven from their habitat by deforestation and other destructive behaviour on our part. Hence, rises in Malaria and other diseases carried by parasites could increase dramatically costing health services millions.
Another example is: small, separate patches of forest and grassland cannot support large roaming predators like coyotes, allowing small prey animals such as the white-footed mouse to thrive. This particular species carries and transmits Lyme disease very efficiently, while larger animals such as squirrels, foxes and coyotes do not. If deforestation hadn’t reduced the forest and grassland areas, coyotes would be keeping the mice in check and Lyme disease would not be such a threat in the US.
We need biodiversity for it’s aesthetical interest and inspiration
Biodiversity is often the subject of aesthetic interest, and as part of the beauty of nature comes from the diversity of life, we should preserve it. Also the diversity of plant and animals inspires scientific interest in many areas. Evolutionary science, anatomy, physiology, behaviour, and ecology are only a few examples. However this isn’t a very compelling argument as there would not be any significant losses if the world weren’t as pretty.
We need biodiversity for the future of the planet
We rely on biodiversity to regulate rainfall, fertilize the soil, soak up excess carbon dioxide, aerate the soil and pollinate the plants. Scientific studies have proven that more complex ecosystems, with more species in them, can make more efficient use of the available natural resources, including the Carbon dioxide which mitigates the effect of global warming. In a study of life on Earth during the past 500 million years, Daniel Rothman found that the greater the biodiversity on the planet, the more CO2 was drawn out of the atmosphere. A study into this revealed Plots containing 16 species of grasses put on five times more extra growth than grass monocultures. The results spectacularly confirm that biologically diverse ecosystems will bloom better in a greenhouse world, and there is no reason why this would not be the same for rainforests and other habitats.
We need biodiversity so we don’t have to conserve endangered species
Biologically diverse ecosystems help to preserve their component species, reducing the need for future conservation efforts targeting endangered species. Many people think that if a reduction in species richness is required to save an endangered animal, then it should be done, despite the ideas that this smashes diversity in that system, and the species you are trying to save is probably reliant upon this not happening. We don’t really know enough to conserve animals effectively so we should attempt to keep a biologically diverse environment so as we don’t need to interfere when we don’t know fully the effects.
We shouldn’t try to protect and increase biodiversity because it’s such a complicated system – we might do more harm than good
We are so far beyond our equilibrium population that we pose a significant threat to everything around us, therefore we are in a position to do massive damage to other species and damage that can come from both negligent behaviour or from misguided attempts to "help". Often in attempts to increase biodiversity, the result has been disastrous. A few examples are:
~ In Australia, rabbits and foxes are driving native marsupials to extinction
~ In New Zealand, weasels have been pushing the Kakapo parrot to its doom
~ In North America, tiny European zebra mussels arrived in the 1980s with shipping, and now clog waterways
~ In the US, once-ubiquitous chestnuts were ruined by an introduced blight
~ In Kenya, the Nile perch has managed to eat its way through 200 cichlid fish species since 1959.
~ in Maryland, the south-east Asian snakehead fish has been chomping its way through native fish and waterfowl since 2002
Also, an increase in biodiversity could be judged to be bad. For instance, The rare Bell-frog live in polluted ponds where few other animals can survive. If these ponds were to be cleaned then the Bell-frogs would probably be driven to extinction but the diversity of life in the ponds would increase dramatically.
We shouldn’t try to protect and increase biodiversity because historically the world is a self-regulating system
Animal and plant species are becoming extinct at an even faster rate than the dinosaurs' disappearance millions of years ago, but why is that such a big problem? The dinosaur extinction wasn't even all that apocalyptic compared to the first big extinction when 90% of all life form species died out but humans still evolved, so what’s the point of worrying about declining/changing biodiversity? The world has supported life through worse declines in biodiversity than what’s happening now. Another example is at the end of last Ice age when climate changed abruptly several times, with Europe and North America ecosystems turning from tundra to forest and vice versa
- So, why should we worry so much about any changes simply because they are through anthropogenic stimuli?
We shouldn’t try to protect and increase biodiversity locally in the interests of conservation of an endangered species
If a protection of endangered species requires a reduction in species richness of some local ecosystems, it should be done without hesitation, especially if this reduction may benefit other ecosystems biodiversity in the long run.
Conclusion
Having looked at the arguments for both sides, I think we ought to strive not to damage biodiversity where it already exists but neither should we attempt to increase it as many attempts at doing this have had disastrous effects on the ecological structures of biospheres. We should protect biodiversity but not try to change it as we don’t have the facts to understand fully how this will affect biodiversity in the long run.