Extinction of species in the geological past might be due to natural phenomenon but the present is quite different.
Although natural phenomenon, like floods, landslides, earthquakes are potent to cause extinction of species, with improvement in technology and advancements in research field humans have become invasive enough to effect the same. For eg. habitat destruction, hunting , use of toxic chemicals, industrialization all account for extinction of species. Also, global warming and acid rains are natural processes which are effected by humans. Global warming leads to climatic and temperature changes and ultimately may cause floods leading to loss of various species. Even Acid rain is adversely affecting many plant species and accelerating their loss.
Being the most active and intelligent animal on Earth it’s our responsibility to maintain the ecological equilibrium. Each species is dependent on every other species for its survival. And many of them form important links in the nature’s cycles. If those links are lost the nature’s harmony will be disrupted.
One must not forget, Humans themselves rely on other species to fulfill their basic needs as well as extravagant desires. Various products like