Aesthetics  An environment with a great diversity of plant and animal species in it can act as a source for art and entertainment, enriching the lives of humans. Thus the preservation of endangered species is an important part of ensuring this diversity continues to exist so people and enjoy and be inspired by the many varied kinds of life on this earth. A good example of this is the re-introduction of the grey wolf into Yellowstone Park in the United States (where it had previously become extinct due to human action), which added to the biodiversity of the region and caused a greater influx of tourists into the park. [1] People enjoy being surrounded by different kinds of nature, and so protecting endangered species is an important part of protecting human enjoyment.  [1] Wilcove, D. S., &amp; Master L. L. “How Many Endangered Species are there in the United States?”. Frontiers in Ecology and the Environment, 3[8]. October 2008.