Viruses have always been a world issue. Epidemics caused by viruses started when human society and lifestyles changed in the Neolithic period. As the new habit of hunting and gathering arose, humans developed more densely populated farming towns and communities, which allowed viruses to spread very quickly and naturally become a large issue. Smallpox and measles viruses are considered to be two of the oldest that infect humans. These two viral diseases evolved from previous viruses that infected other animals, and so they first appeared in humans in Europe and North Africa thousands of years ago. Viruses have been evolving just like those two to become more adapt to their surroundings and better thrive. This project focuses on the evolution processes viruses take in order to acclimatize themselves to their surroundings and continue to thrive, and how this affects the organisms they infect. I will further examine how viruses replicate and mutate in ways made by possible by reverse transcriptase enzymes and other actions. There is at least 320,000 known viruses that infect mammals around the world. I plan on focusing on about five newly evolved viruses: West Nile Virus of North America (WNV), Bird Flu Virus (H7N9), Swine Flu (H1N1), Hepatitis A Virus (HAV), and the Influenza A Virus. I believe that these viruses evolved their nucleoprotein genes, amino acids, nucleotides, and other structures to help themselves. I plan on using sites such as cdc.gov (Centers of Disease Control and Prevention), asm.org (American Society of Microbiology), and many others to help me prove my belief in the viruses’ processes.