All scientists know that sometimes (okay, frequently), experiments don’t go exactly as planned. Maybe you forgot about a bacteria plate stashed in the back corner of the incubator for a month, or you treated cells with five times the concentration of drug that you meant to. But sometimes mistakes in the lab can actually be blessings in disguise. Without leaving those plates in the incubator, you might never have seen that strange new phenotype that only your mutant bacteria have, or it might have taken you forever to realize that you actually weren’t even close to the effective drug concentration needed to treat your cells.
These happy accidents can lead to exciting breakthroughs in science, and they happen more often than we realize. There’s Alexander Fleming’s discovery of penicillin from mold contamination on a bacteria plate. And Wilson Greatbatch was trying to engineer a device to record heart rhythms when he accidentally created the pacemaker.
Although not as revolutionary as penicillin or the pacemaker, part of my own doctoral research would not have existed without a happy accident. Before I joined microbiologist and parasitologist Kent Hill’s laboratory at the University of California, Los Angeles, graduate student Miguel Lopez and postdoctoral researcher Michael Oberholzer had discovered that the parasite Trypanosoma brucei engages in social behavior when placed on a surface. Of course, T. brucei are not social in the same way that mice are when they groom and play with each other. T. brucei are more like bacteria when they form biofilms or swarm across surfaces. T. brucei move together in groups to form long thin lines of parasites.
Typically, we performed our social behavior experiments in sterile conditions to prevent other microbes from landing and feasting on the nutrient-rich parasite plates, but one day, Lopez and another graduate student, Edwin Saada, noticed a small bacterial colony growing on the same plate as the social parasites. Lopez and Saada could have thrown this plate away and started over, but instead, they kept it in the incubator and watched over the next few days as the social parasites started to move as a group toward the bacteria. Researchers had only ever seen groups of social T. brucei avoid each other, never move toward something before. This was a brand-new behavior, and one that I had the opportunity to characterize more fully. We would have never discovered this behavior without this accidental contamination.
All of this is not to say that scientists should go out of their way to make mistakes! It’s more to know that mistakes will happen and to look at them as potential opportunities for learning something new rather than seeing them as something bad. So, when you accidentally add too much of a reagent or crank open the -80°C freezer and pull out a missing tube of cells from the snow on the bottom shelf, don’t sweat it. It might hold science’s next big breakthrough.
- Oberholzer, M. et al. Social Motility in African Trypanosomes. PLoS Pathogens 6, e1000739 (2010).
- DeMarco, S.F. et al. Identification of Positive Chemotaxis in the Protozoan Pathogen Trypanosoma brucei. mSphere 5, e00685-20 (2020).