While looking for a postdoctoral position, Michael Mitchell could have joined any number of small, intimate labs with a couple of colleagues and an ever-present lab leader. Instead, he decided to go big. In 2014, after earning a PhD in biomedical engineering, he accepted an offer from Robert Langer, also a biomedical engineer, at the Massachusetts Institute of Technology (MIT) in Cambridge. Mitchell shares the lab with some 40 other postdocs, a host of graduate students and a rotating cast of visiting researchers. The sheer scale of the enterprise becomes clear every summer, when the lab gathers for an annual party at Langer’s beach house. “Bob has to rent three to four buses to get us down to the house,” Mitchell says. “He gets an entire ice-cream truck for dessert.”
Of all the factors that potential postdocs must consider when choosing a position, lab size should be near the top of their list: it can shape a junior researcher’s career. Scientists say that small labs may be isolating, but that members tend to have great access to the lab leader. Conversely, whereas trainees in larger labs may have less time face-to-face with their mentor, some data suggest that they have more chances to collaborate and publish.
Those considering a postdoc position should think carefully about what would suit them. “It’s quite a personal choice,” says Kerstin Kinkelin, the training and career-development project manager at the Francis Crick Institute in London. “There’s no general rule about which is better or worse, but people need to think about which lab size works for them personally.”
A large lab was the right choice for Mitchell. “I knew Bob’s lab would have the resources to allow me to pursue the range of research ideas that I’m interested in,” he says. “But I was also looking for an excellent mentor. I would have worked for Bob even if I was the only one there.”
