In 1859, Charles Darwin published the book On the Origin of Species, where he wrote about his journey to the Galapagos Islands. On these islands, Darwin discovered the theory of natural selection. Natural selection is a mechanism of evolution, in which organisms with favorable traits survive and reproduce overtime. In short, it is “survival of the fittest.”

Darwin discovered natural selection when he found 18 finch species that all differed in beak size and shape. Some species had long, narrow beaks, while others had short, wide beaks. This was interesting because the finches inhabited the same geographic area, yet had evolved to have different characteristics for different food sources. When variations of species rapidly evolve overtime to fill specific ecological niches , it is called adaptive radiation.

From the finches, Darwin theorized that this type of evolution naturally occurs overtime. Certain finches were favored over others because of what they ate, and were thus naturally selected for. As a result, the surviving finches would reproduce with other surviving finches, increasing that specific beak in the gene pool across generations. In this lab, you will simulate the natural selection of Darwin’s finches and their fight for survival on the Galapagos Islands.