why should we care about the loss of biodiversity? Perhaps the purest reason is our biophlilia, our sense of connection to nature and other forms of life. But addition to the aesthetic and ethical reasons for preserving biodiversity , there are practical reasons as well. Biodiversity is a crucial natural resource, and species that are threatened could provide crops, fibers,and medicines. In the United States,25% of all prescription dispensed from pharmcies contain substances derived from plants.