At the recent workshop I attended, one of my colleagues remarked that all the members (past and present; male and female) of a particular research group resembled each other: they were all fit, attractive, had short hair, and most of them were tall, just like the professor who heads this group.
Over the years I have observed other examples of research group members resembling each other. For example, another research group with which I am familiar is mostly comprised of thin men with beards. Just like their supervisor, all of the students and postdocs are runners, though some became runners after joining the group.
The ones who previously had no interest in running are the ones who concern me. I can see why they don't want to be left out, but what if someone doesn't want to train constantly to run 10k races? Would such a student be less likely to be accepted to work with this group?
As a postdoc, I was in a research group in which I (the only woman) was the only one who did not have an interest in a particular extreme sport. My lack of interest in this sport (and certain death) didn't exclude me from being hired, but I was definitely left out of the reindeer games at which scientific discussion occurred. That's a classic problem experienced by anyone who doesn't share the characteristics or interests of the majority, but in the case of sports or hobbies, in theory you can become part of these activities.
In some cases, research group resemblance stems from the fact that group members dress alike (= convergent evolution). For example, I recall the vivid sight at a conference of numerous turtlenecked male graduate students gathered around their turtlenecked advisor. They all had their hair cut in approximately the same way and none had facial hair. They looked like they were in some kind of dorky cult.
When I was a graduate student, one of my fellow students took to wearing the same kind of tweed jacket-turtleneck combo as our advisor wore (what is it with turtlenecks?), and he attempted the same style of facial hair. I thought this was bizarre. I never figured out the motivation for this type of mimicry, and don't know whether it was done deliberately or subconsciously.
The question is: Do members of some research groups 'evolve' to look like each other (typically by altering their clothing and hair style and perhaps acquiring certain hobbies) or do some advisors tend to select advisees who have certain characteristics and interests?
I think the answer is both, maybe.
If 'selection' occurs, it may involve people with similar interests gravitating towards each other because they feel most comfortable with this situation. The danger of this of course is that 'other' people might be excluded, even if not deliberately, and that many of these other people may be women or members of other underrepresented groups.
I suppose it is natural to want to feel like part of the team if you're working in a research group, and perhaps dressing alike is a benign part of that effort, as long as the team is diverse in other ways.
Some of this type of superficial resemblance can be unintentional. I was once walking with 2 of my grad students, when we suddenly realized we were all wearing the exact same kind of rain jacket. I immediately thought of the Cult of the Turtleneck and felt anxious. It turns out we had all gone to the same sale at a local store. At least we had each selected a different color jacket. In fact, one of my students asked me if I had gotten to the sale late, perhaps in reference to my unusual color choice. And he was right.
I don't think I selectively accept grad students who share characteristics or interests with me, but maybe it is hard to escape from this tendency entirely. I was once taken aback when meeting a prospective grad student at a conference. She was wearing a Winnie-the-Pooh shirt, and I wondered why someone would wear something like that at a conference. But then I thought: Is that any more juvenile than a young man wearing a baseball cap? Why does it matter what she (or a baseball capped guy) is wearing? I had to talk myself into this, though, but in the end I think I convinced myself. I don't want to work only with people who are just like me.
1 day ago