Putting It Together: Theory of Evolution


In this competency you learned about these topics:

  • Charles Darwin’s’ observations of natural selection that ultimately led to the theory of evolution
  • the multiple types of evidence that support evolution by natural selection
  • how mutations form the basis of microevolution
  • phylogenetic trees as a way to organize our understanding of evolutionary relationships


Based on what you’ve learned, let’s return to our discussion of evolving bacteria. The World Health Organization (WHO) suggests that based on current evidence, gonorrhea may soon be untreatable; there are no new treatments or vaccinations in development for this bacteria. Within the United States this remain the second most common sexually transmitted disease. Almost a third of the US cases are drug resistant. MRSA remains a growing problem in our healthcare system. Staph bacteria are the most common source of health-care related infections in the United States. Of MRSA infections, nearly 14% result in death.

Based on this lesson you now understand that evolution is an inevitable process. Is there any hope of stopping antibiotic resistance from developing? Yes and no. The average person can take a number of steps to minimize selective pressures on parasites. Without these pressures, mutations are less likely to spread in the population. So what can you do?

  • Take the full course of prescribed antibiotics
  • Don’t save or share leftover antibiotics
  • Don’t ask for antibiotics if your doctor does not recommend them
  • Practice good hygiene and get recommended vaccinations
  • Minimize your use of antibacterial products

Here are some interesting websites on the subject: