Natural selection is the process by which a population develops a more pronounced expression of a particular trait or loses a particular trait that will enable it to survive in the prevailing environmental conditions. Natural selection is the foundation of the evolution of a population species. A good example, as discovered and explained by Charles Darwin, is the phenomenon of Darwin’s Finches as found on the Galapagos Islands.
The finches are a type of bird that is unique to the Galapagos Islands. These Finches are a type of bird whose beaks have developed and evolved very differently to enable them to survive on the island, thereby eliminating competition, and consequently ensuring their continued survival. Initially, it can be said that the finches were one large species that fed on the same type of food material. However, there was a development of their beaks in a manner that enabled them to feed on different types of food materials that were available on the island due to their increased population growth and consequently a decrease in the food supply, thereby minimizing competition and ensuring their continued survival.
This idea was discovered by Darwin during his voyage to the island where he found out that there were various categories of the same type of bird, and this he called species. Of these species, there was no clear-cut difference in the type of beaks concerning the size and shape. On the contrary, he found out that in between the four major classes of beaks, there were intermediary types of beaks with a graduating size and shape. This could only mean that the beaks were in different stages of evolution in total. He recorded fifteen species of finches in four genera. These genera include Geospiza, which has seven species, Camarhynchus, which has six species, Certhidae and Pinaroloxias, which have one species each. The availability of food was the environmental factor that led to their evolution into different species.