As science unfolds the secrets of nature, we come to realise that we are totally dependent on the functioning of most forms of life. This is called ecosystem services. In short these are the activities of wildlife that support the lives of humans and other organisms. We are actually dependent on almost all species in some way or another. Many of these services we take for granted because they are silently always there functioning normally and providing for our needs. For example, about 70% of the oxygen that we breathe emanates from photosynthetic plankton in the vast oceans. It is released into the atmosphere and then circulates around the globe. The remaining 30% will come from the plants of the land and fresh-water habitats.
Pollution has always been a problem. Before motor cars were invented, people relied on horses. However, as London grew larger, the number of horses was so large that the streets were getting clogged with horse manure. It became a crisis until motor vehicles provided a solution. However, in the countryside, the dung disappears very quickly. This is because there are species of beetle called dung beetles. Some of these roll it up into little balls, then roll the balls to an appropriate place, lay their eggs in it and then bury it underground. Soon the beetle larvae hatch out and actually eat the dung and it then becomes part of the enriched soil. There are also dung flies that are completely harmless but also lay their eggs in the dung and the fly larvae eat it and then turn into new dung flies and so on. There is an amusing story about the first European settlers in Australia who took large numbers of cattle and sheep there. However, the Australian insects could not cope with the amount of dung that these strange animals produced, so the settlers had to collect dung beetles from Europe and introduce them into Australia in order to provide a service to the cattle ranchers.
It is interesting to note that almost all of the food produced on the terrestrial parts of planet earth emanates from the top 20 centimetres of soil. If it was not for the insects, crustaceans, earthworms and microbes that live in this soil, nothing would grow. We all need the biodiversity that makes up the family of life on this planet, and unless we strive to preserve it, we will end up like an astronaut on the surface of the moon without a space suit.
Dr. Martyn Stenning