Provide information on the history of species extinction and state its effects.

(N/A) Since the origin and diversification of life on Earth $3$ billion years ago,there have been five episodes of mass extinction of species.
The current rate of species extinction is estimated to be $100$ to $1000$ times faster than the natural rate. If this rate of extinction continues,it is estimated that nearly half of all species on Earth might be wiped out within the next $100$ years.
The loss of biodiversity leads to:
$(a)$ $A$ decline in plant production.
$(b)$ Lowered resistance to environmental perturbations such as drought.
$(c)$ Increased variability in certain ecosystem processes such as plant productivity,water use,and pest and disease cycles.