What is ‘biodiversity’ and why does it matter?
Biodiversity, according to the UN Convention on Biological Diversity, is the “variability among living organisms… and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems”. Basically, the more variety there is in any given ecosystem – whether on the scale of your backyard to the entire European landmass – the more biodiverse it is. The concept of variety applies not only to species, but to different kinds of the same species (for example, see this list of types of pumpkin) and to entire ecosystems (e.g. marine, jungle, wetland, temperate rainforest).
Biodiversity matters in a huge number of ways, including in terms of environmental health. Biodiversity improves ecosystem resilience by allowing them to adapt more easily and to recover from external stresses such as climate change. For example, in 2006 a researcher named David Bellwood (cited in Mission 2015: Biodiversity) fenced off an area of the Great Barrier Reef to prevent fish and other marine animals from interacting with the coral. The point was to determine what the effect of overfishing to the point of extinction (or, presumably, some other process with the same effect) would be on the reef. In the absence of other marine life the reef quickly became overgrown with algae, and the study indicated that it would eventually have died. When the fences were removed the bat fish – a fish normally considered by scientists to be insignificant in the reef environment – played a key role in allowing the fenced area to undergo a rapid recovery.