The Rise of Superbugs
Understand antibiotic resistance and the rise of superbugs: learn how natural selection drives bacteria to evolve resistance when antibiotics kill susceptible bacteria but leave resistant mutants to reproduce.
Key Concepts
The principles of Natural Selection apply to all living things, including microscopic bacteria. We can explain the global health crisis of "antibiotic resistance" using the exact same model used for newts and sticklebacks.
1. Variation via Mutation: In any large population of bacteria, random mutations occur constantly. By chance, a few bacteria might possess a mutation that makes them resistant to a specific medicine, while the rest are vulnerable.
Common Questions
How do superbugs develop antibiotic resistance?
When antibiotics kill most bacteria in a population, any bacteria with random mutations that confer resistance survive and reproduce. Over generations, the resistant trait spreads through the population.
Why is antibiotic resistance a natural selection event?
Antibiotics act as an environmental pressure that selects for resistant bacteria. Susceptible bacteria die; resistant ones reproduce — the classic mechanism of natural selection driving evolution.
What can students do to help slow superbug development?
Taking full antibiotic courses ensures all bacteria are killed, preventing partial resistance from evolving. Avoiding unnecessary antibiotic use reduces selection pressure that drives resistance evolution.