Question

How many mass extinction of species are there on records since the origin and diversification of life on earth? How is the present episode different? What is the result of loss of biodiversity in a region?

Answer 1

Since the origin and diversification of life on earth,there have been 5 mass extinctions.Apart from this,in the last 350 million years ,there were about 4 mass extinctions that led many species disappearance within a very short period of geological time scale.These were :"Permian–Triassic extinction event , Olson's Extinction, Cretaceous–Paleogene extinction event.The present episode is different in a way that humans are the main cause of the mass extinction which is known as Holocene extinction.Previously ,it was the environmental factors that caused mass extinction and now it is the humans those are paving the way for the mass extinction.The result of loss of biodiversity in a region can lead to extinction of plant,anial or even human species as a result of which there would be a dramatic change in the food web and food chain and ultimately the whole web of life that exists will collapse.