I was talking to a fellow grad student yesterday who is facing the prospect of being entirely alone in her lab next year. It just so happens that the senior PhD students and post docs in her lab are all leaving. If no new post docs join her lab next Fall, my friend will have only her advisor to go to for help. This isn’t a good situation. Yes, we grad students are expected to be fairly independent at this advanced level, and a good advisor is certainly helpful, but very often we need the help of more experienced students and post docs to be successful. This is especially true in laboratory settings, where the advisor (or P.I.) probably doesn’t spend much time in the lab and may be unable to teach us lab protocols or troubleshooting tricks. Ideally, there is stratification in the lab: students representing multiple levels of seniority are present as well as post docs. In stratified labs, incoming students are taken under the wings of older students and given enough guidance to avoid the mistakes of those who have gone before.
This is probably analogous to large families that work on farms and stuff. The parents have precious little time to teach routine skills to each new child, so the older siblings step in and do the job. Younger children benefit from the practical knowledge of their siblings. The oldest child only had their parents to learn from and had to suffer through many trial-and-error experiences. This is what happened to me, except that I am an only child, so I never got to pass down my hard-won wisdom.
Stratification has been immeasurably important in the advancement of human culture and technology. Lucky for us, we have overlapping generations (not to mention writing!) so that older people can teach younger people what they learned from the preceding generation as well as what new knowledge they accumulated in their own lives. Nobody should have to “reinvent the Wheel.” Imagine how things would be if every human being was born simultaneously and had no one from the previous generation to learn from. All culture and knowledge would have to be generated de novo, from scratch. It just wouldn’t work, would it?
My own advisor has said that he tries to maintain a stratified lab and I think this should be an explicit goal of all professors who have graduate students. It’s not always feasible to keep a nice level of stratification, and some students do just fine by working things out on their own, so stratification doesn’t have to always be a top priority. However, I think that the continuity of knowledge and culture in a laboratory is best maintained the way human culture is maintained: through the flow of knowledge from one generation (or cohort or whatever) to the next.