5 Mass extinctions

 

It was during a visit to the Toyota Kirloskar plant in Bidadi near Bangalore that I first came to see with my eyes some of the flora that existed on planet earth 440 million years ago. In this brief write up of mine, I am trying to describe why mass extinctions (also called biotic crisis, resulting in loss of diversity in the environment). In this brief write up I am giving some pictures of the early 5 mass extinctions that have happened on planet earth over the past 440 million years. These mass extinctions have resulted in an average loss of life, of flora and fauna, in the range of 70 to 85% of all species on planet earth. 

An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the biodiversity on Earth. Such an event is identified by a sharp change in the diversity and abundance of multicellular organisms. It occurs when the rate of extinction increases with respect to the rate of speciation. Estimates of the number of major mass extinctions in the last 540 million years range from as few as five to more than twenty. - wikipedia.org

Extinction is the rule, survival is the exception - Carl Sagan

 

Why are we interested in studying these things is because we humans aere causing the next mass extinctions in the Haliocene age and we humans are responsible for it. 

Mother Nature creates some many species that its replenishment happens as a natural rule, a common activity than an exception.

A mass extinction event is when species vanish much faster than they are replaced. This is usually defined as about 75% of the world's species being lost in a 'short' amount of geological time - less than 2.8 million years - nhm.ac.uk