Lessons Learned in Graduate School: Be Skeptical

Part 1 in a series of posts on “Lessons Learned in Graduate School.”

Two hours. Four hours. Overnight, if I have the time.

I must have asked half a dozen people, and I didn’t get the same answer twice. The question had been: How long do you incubate pelleted virus in fresh media before resuspending and aliquoting it? But the question is not the point. The point is that I asked every senior student in my lab how to do a basic, standard lab protocol, and all of their answers were different.

Lesson learned: Every graduate student — and every scientist, really — does science a little differently, even researchers who learned the same protocols in the same lab from the same mentor.

So I did the experiment. I pelleted some virus and incubated it, taking hourly samples to determine the optimal incubation time. The goal was the highest concentration of resuspended virus with the shortest incubation. But, again, the goal is not the point. The point is that the whole incubation step turned out to be superfluous. As long as I handled the sample correctly, the incubation — whether for an hour, four hours, eight hours, or even overnight — had zero impact on the final concentration of the virus. In other words, I could save myself anywhere from two to 16 hours every time I did this protocol by skipping the incubation step altogether.

Lesson learned: Senior graduate students and postdocs don’t know everything.

Everyone I asked about this protocol was sure that they knew what was best, and they all turned out to be wrong. They cited anecdotal advice from legendary former lab members and wrinkled paper protocols written so long ago that they may as well have been etched in stone. These senior students didn’t cite published papers. And perhaps worse, they didn’t cite personal experience. They told me, “I know this is the right way to do X,” without ever having tried to do X any other way.

Now that I’m a relatively senior graduate student myself, younger students ask me questions all the time. When I answer, I remind myself to add the disclaimer, “I’ve never tried that, but…” to any advice I don’t have direct evidence for. It’s hard to admit that I don’t really know whether various modifications would make a difference when talking about lab techniques I’ve been doing for years. But all I can really say for sure is that the way I’ve always done things definitely works.

So here’s my advice to junior graduate students: Always ask questions. The senior graduate students and postdocs have years of experience, and they can help you so much. But when you ask a question, also ask to see data that back up the answer. As Benjamin Franklin once so appropriately said, “believe none of what you hear, and only half of what you see.”