This has been my first semester involved in research, and I had a sudden realization the other day: from the undergraduate point of view, research labs function according to the feudal system.
The monarch is probably the dean of academics or something along those lines. Principal investigators (PIs) are like nobles, wielding great authority in a limited area-- their lab. PIs have lesser nobles and knights to manage day-to-day work in the lab; these are postdocs and graduate students. Lastly, there are peasants, undergraduates that often do much of the basic work in the lab.
Now, this may seem like a negative view of research, but the reciprocity of the feudal system shouldn't be forgotten. Just as serfs work for a noble in exchange for a place to live and protection, a PI maintains the loyalty of graduate students and undergraduates by providing resume-building research experience and mentoring. PIs also look out for their subjects when they write letters of recommendation or help them network with other researchers.
There are, of course, differences between the two systems. For one thing, it's possible to progress to the top of the research hierarchy in a few decades; the medieval feudal system provided much less social mobility. That being said, the similarities are clear to see. In a good lab environment, there's no doubt as to who's in charge, but everyone is happily engaged in the work being done.