Why is biodiversity essential to the health of the environment?

Ecosystems that lose biodiversity, the range of organisms present become more fragile and susceptible to collapse. This is because no species lives independent of other species. All species are interdependent, connected in a web of life that forms the foundation of the ecosystem. Consider a large beach house as if it were an ecosystem and the dozens of pilings supporting it as representing the species in that ecosystem. Together, the pilings support the house and make it stable. Sure, you might be able to remove one piling and the house would still stand. Or maybe you could remove two or three. But how many could you safely remove? Eventually, the house will collapse. The same is true of ecosystems: With the loss of each species, the possibility of a catastrophic collapse increases. A selfish reason for preserving biodiversity is that most drugs are derived from some plant or animal. Because of genetic diversity among species, different creatures produce an extraordinary range of chemical compounds. We continually test new species for their potential to help fight disease and we find wonderful medicines. But extinction is claiming species each day before we can learn about them.