Why is Biodiversity Important? Does it really matter if there aren’t so many species?

A diverse ecosystem is important. Biodiversity actually boosts ecosystem productivity where each species, no matter how small, all have an important role to play. It is this combination that enables the ecosystem to possess the ability to prevent and recover from a variety of disasters.

This is obviously useful for mankind as a larger number of plant species means a greater variety of crops. In addition, a larger number of species of animals ensures that the ecosystem is naturally sustained. And so, while we dominate this planet, we still need to preserve the diversity in wildlife.

A healthy biodiversity offers many natural services

A healthy biodiversity provides a number of natural services for everyone:

• Ecosystem services, such as
  • Protection of water resources
  • Soils formation and protection
  • Nutrient storage and recycling
  • Pollution breakdown and absorption
  • Contribution to climate stability
  • Maintenance of ecosystems
  • Recovery from unpredictable events
• Biological resources, such as
  • Food
  • Medicinal resources and pharmaceutical drugs
  • Wood products
  • Ornamental plants
  • Breeding stocks, population reservoirs
  • Future resources
  • Diversity in genes, species and ecosystems
• Social benefits, such as
  • Research, education and monitoring
  • Recreation and tourism
  • Cultural values

That is quite a lot of services we get for free! Now, as we erode ecosystems and reduce biodiversity, based on the above list of things we start to lose, the cost of replacing these (if possible) would be extremely expensive. It therefore makes economic and development sense to move towards sustainability.

A report from Nature magazine also explains that genetic diversity helps to prevent the chances of extinction in the wild (and claims to have shown proof of this). To prevent the well known and well documented problems of genetic defects caused by in-breeding, species need a variety of genes to ensure successful survival. Without this, the chances of extinction increases. And as we start destroying, reducing and isolating habitats, the chances for interaction from species with a large gene pool decreases. Side NoteUnfortunately the original link to the Nature.com article no longer works, since their site redesign, and I had not noted the publication details. However, for similar information, you could look at Consequences of changing biodiversity, Nature 405, 234 - 242, 11 May 2000 and Causes, consequences and ethics of biodiversity, Nature 405, 208–211, 11 May 2000.

Species depend on each other

While there might be “survival of the fittest” within a given species, each species depends on the services provided by other species to ensure survival. It is a type of cooperation based on mutual survival and is often what a “balanced ecosystem” refers to.

As an example, consider all the species of animals and organisms involved in a simple field used in agriculture. As summarized from Vandana Shiva, Stolen Harvest (South End Press, 2000), pp 61–62:

• Crop byproducts feed cattle
• Cattle waste feeds the soil that nourish the crops
• Crops, as well as yielding grain also yield straw
  • Straw provides organic matter and fodder
  • Crops are therefore food sources for humans and animals
  • Soil organisms also benefit from crops
    • Bacteria feed on the cellulose fibers of straw that farmers return to the soil
    • Amoebas feed on bacteria making lignite fibers available for uptake by plants
    • Algae provide organic matter and serve as natural nitrogen fixers
    • Rodents that bore under the fields aerate the soil and improve its water-holding capacity
    • Spiders, centipedes and insects grind organic matter from the surface soil and leave behind enriched droppings.
    • Earthworms contribute to soil fertility
      • They provide aerage, drainage and maintain soil structure.
      • According to Charles Darwin, “It may be doubted whether there are many other animals which have played so important a part in the history of creatures.”
      • The earthworm is like a natural tractor, fertilizer factory and dam, combined!
• Industrial-farming techniques would deprive these diverse species of food sources and instead assault them with chemicals, destroying the rich biodiversity in the soil and with it the basis for the renewal of the soil fertility.

Shiva, a prominent Indian scientist and activist goes on to detail the costs associated with destroying this natural diversity and traditional farming techniques which recognize this, and replacing this with industrial processes which go against the nature of diversity sustainability.

Bees provide enormous benefits for humankind as another example. As reported by CNN, “One third of all our food—fruits and vegetables—would not exist without pollinators visiting flowers. But honeybees, the primary species that fertilizes food-producing plants, have suffered dramatic declines in recent years, mostly from afflictions introduced by humans.” (May 5, 2000).

More important than human use or biological interest

Many people may support environmental causes to help preserve the “beauty” of Nature. However, that is in a strange way, not really a justifiable excuse as it is a subjective, human or anthropomorpahsized view. Instead, a logically sound reason based on ecological factors would help show that biodiversity is more important than people realize.

For more information on this question, visit some of the following links

• Scientific American Magazine provides an answer to a reader’s question: “What is the point in preserving endangered species that have no practical use to humans, apart from their aesthetic appeal or their intellectual interest to biologists?”
• The WWF also have a section on this issue.
• Biodiversity: A Matter of Extinction is a briefing from Panos that highlights the current problems that have led to an increasingly alarming rate extinctions, this century alone.
• Biodiversity—an Overview from the World Conservation Monitor provides many good reasons and insights.
• Biodiversity and its Value from the Department of the Environment and Heritage, Australia, provides many good insights.
• What is Biodiversity? from Rutgers University provides a good list of things to consider.
• “Why Conserve Species” from Nature Magazine provides a good answer to this question. (Unfortunately, since their site redesign, this URL is no longer valid, and to date a new URL cannot be found.)
• “Life on the Brink” from Earth Magazine, (Kalmbach Publishing Company), April 97 edition, delivers a very interesting answer that is worth a read. (Unfortunately they no longer publish this magazine so the article is no longer online.)
• Biodiversity Benefits People is an online presentation from the United Nations Environment Program
• What is Biodiversity? from the Biodiversity Project also provides answers to why biodiversity is important