Of all the species that have lived on the Earth since life first appeared here 3 billion years ago, only about one in a thousand are still living today. All the others, the vast majority, became extinct, typically within ten million years or so of their first appearance. This large extinction rate has had an important influence on the evolution of life on Earth. Humans are presently causing the record mass extinction of species since the …showed first 75 words of 757 total…

…showed last 75 words of 757 total…faunal assemblages. Within this progressive mass extinction pattern, catastrophic events, or the attainment of threshold conditions, may hasten the demise of weakened species leading to patterns of abrupt or sometimes stepwise extinctions. In conclusion, we can and must become a society that appreciates the importance of biodiversity and how to preserve it from extinction, not only for the flora and fauna that is at risk but for the well being of man kind as well.