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Health and Mechanisms of Evolution

When the first antibiotic was developed in the 1940s, it was the solution to a huge health epidemic. Since then, dozens of new antibiotics have been made that are able to kill harmful bacteria. You've probably taken them a few times in your life. Antibiotics are generally pink bubble gum flavored goodness.

Antibiotics were as revolutionary as the iPhone. Figuring out how to kill bacteria and stop infections and disease? A trip to the Genius Bar. We've been riding the antibiotic invention for a long time. What was once a brilliant move has now turned into a different kind of epidemic. Bacteria are quickly becoming resistant to our best way to stop them. These antibiotic-resistant bugs are being called superbacteria. Is there an app for that? We wish.

The problem is that bacteria can evolve by natural selection just like the rest of life. Bacteria also have an upper hand on evolution. They are able to go through multiple generations in an hour, which means natural selection can happen quickly.

When we pick up a prescription of antibiotics from the pharmacy, there is usually a label on it that tells us to take the entire bottle, even if we start to feel better. There's a good reason for that. When a population of bacteria is hit by antibiotics, most of them will die off. However, due to their fast generation time, they can also accumulate mutations fast. If one of them develops an adaptive mutation, it will start to multiply. It's important to kill all of them before this can happen. This also explains why it's important not to use antibiotics when you really don't need them. It gives these superbacteria a chance to develop resistance.

Superbacteria are making their way around the world, passing their adaptive mutations on to other populations via gene flow. More than one species has antibiotic resistant strains using similar mechanisms of adaptation, including E. coli and Salmonella. These bugs are usually found in hospitals, where people with low immune systems are more likely to be affected. They have also been found in drinking water in India.

We can't stop bacteria from evolving resistance to antibiotics. It's a scary international health crisis. While science is trying to find new ways to get rid of bacteria, there's a few things the rest of us can do to help out. Only take antibiotics when absolutely necessary. When you're prescribed antibiotics, take the full dose. And last but not least, wash your hands, yo.

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