One of the most important principles of biology is the main idea of ​​evolution. This theory states that “all living organisms evolved from a common ancestor through natural selection acting on heritable variation” (Reece, 2011). Many people today know that humans evolved from a common ancestor; but they do not recognize its importance. Everyone should be informed about how organisms have evolved because humans have evolved over many centuries. Charles Darwin had many theories that incorporated the fundamental principles of biology, natural selection, and evolution. Darwin explained natural selection as an evolutionary change in which organisms that are better adapted to their environment survive better than those that do not (Natural, 2004). Through evolution and natural selection many species, including humans, are here today. Charles Darwin founded the principle of natural selection, which describes how organisms that adapt better in an environment will survive better and produce more offspring (Natural, 2004). Darwin first noticed evolution after visiting the Galápagos Islands; here, he noted that geological separation played an important role in how organisms adapted and formed new species (College, 2009). When species live in a new environment, they adapt differently and eventually these organisms will change over time, a process known as evolution (College, 2009). Darwin noticed that birds from another Galapagos island also have similarities and differences. He believed that these birds were once the same species but due to evolution they became different species. He noted that “different species display different beak morphologies (size and shape) that are suited to the exploitation of different food resources… focus of the article……7040903504823McCullough, M.E., & Pedersen, E.J. (2013 ).The evolution of generosity: How natural selection builds benefit-providing devices.Social Research, 80(2), 387-410.Milot, E., & Pelletier, F. (2013). new playgrounds for natural selection. Current biology, (10), doi:10.1016/j.cub.2013.04.040 Natural selection: how evolution works (2004). /www.actionbioscience.org/evolution/fNatural Selection: How Evolution Works. (n.d.). Retrieved March 16, 2014, from http://www.actionbioscience.org/evolution/fuNatural Selection. how it works. Retrieved February 26, 2014, from http://evolution.berkeley.edu/evosite/evo101/IIReece, J.B. and Campbell, N.A. (2011). Campbell Biology Jane B. Reece ... [et al.]. (9th ed.). Boston: Benjamin Cummings.