THE GREAT EPIDEMICS OF HISTORY

This displacement translates into earthquakes, volcanic eruptions, alteration of ocean currents and the formation and elevation of mountain ranges, all of which profoundly affect the climate, forcing evolutions, the emergence of new species or extinctions, sometimes mass extinctions.
When we mention evolution, we usually assume that it affects large forms of life, we are inclined to leave aside microscopic beings to contemplate with fascination the transformation of animals that originated the great saurians or, more recently, the amazing evolution that led to the whale, mammals and the Human Being.
However, it is interesting to note that what for a mammal is just a handful of days, or a month, for a virus represents a sufficient number of generations to complete an adaptation to new environments.