This post was inspired by FSP's post of the same title, about the difficulties of spotting future researchers at the early stages.
Basically, FSP says it's hard. I say it's not. But I'm also the kind of person who would rather have no one in my lab than have the wrong people.
Here's how I describe the qualities of good researchers. I think these qualities are evident good researchers of all ages, even pre-PhD (note the sarcasm).
1. Good bullshit detector. Critical thinking. Objective thinking. Unwillingness to take anything on faith.
How to spot it: Journal clubs. If a student at the undergraduate level can't stand up and critically assess a paper, it's unlikely they will suddenly acquire that ability in grad school. If you don't think undergraduates can handle journal club, think again. They can and should be reading and discussing primary literature.
2. Creativity. Someone who is looking for what hasn't been done, and how it might be done in the future.
How to spot it: Do they ask good questions in class? In lab meeting?
Yes, I think undergraduates should volunteer in labs or work there in the summer at least once before applying to grad school. I would NEVER take a grad student who had not worked in a lab at least for 1 summer before applying. EVER.
3. Spine. You want someone who has their own opinions, will stick up for themselves, and will persist through the usual level of obstacles.
The last thing you want is someone who is book-smart but caves at the slightest setback or panics when things don't match exactly with the textbooks/journal articles.
How to spot it: This is the kind of thing you can tell from two tests if you know what you're looking for.
First, the interview. Ask this person if they've had any obstacles in their life. It could be anything. It will be illuminating.
The best student I ever had came from a family that ran their own business. She had a fantastic work ethic, and a fabulous no-nonsense attitude about everything.
More recently I had a prep-school student who knew the value of hard work through her sports training. She wouldn't take any crap from anybody, and she was always willing to speak her mind.
Second is in the lab. I've written before about how I think it's absolutely necessary to give undergraduates real projects, not pre-cooked kits like in lab classes (I think lab classes are worthless, and have blogged about it before).
Real projects are the best. This will tell you how they handle problem-solving and give them a real taste of what grad school will be like. You might not expect them to actually be able to solve any problems on their own at this stage, but watch for their reaction to the inevitable setbacks.
If they want to do something only once and then move on, beware! If they want to quit after 1 try that doesn't work, there's your answer! And theirs, too. The ones who can't handle failure cannot handle research, and they usually figure this out once they've had a taste of it.
4. Street smarts. By this I mean, someone who has common sense, who already has basic study skills, is at least somewhat organized, pragmatic, and not likely to get hung up on doing something one way when there are a variety of tools within easy reach.
How to spot it: Do they take notes? I require my students to take notes. That is non-optional. If they are not okay with that, they don't work with me. And I check their notebooks. The good ones grasp the concept that they will not remember everything. Even better are the ones who care that their notebook is the only record I have of what they did. The notebook tells you a helluva lot.
Are they willing to go look things up if they don't know them? One student really impressed me with this. We had a long discussion about how to do a calculation, and my way just was not working for her. The next day she came back and told me she discussed it with one of her instructors and came up with another way that would also get the job done. Bravo! I say. This is exactly what you're looking for in a researcher.
I also file a certain amount of maturity in this category. Do they keep a calendar? Are they always late and always making excuses?
Experiments are not forgiving of sloppy time management, and you shouldn't be, either.
5. Attention span. Most of the people I know who left research quit because they got bored easily. They enjoy the constant flow of new ideas that they get in patent law and science journalism. They did not want to work on the same project, or aspects thereof, for the rest of their adult lives.
How to spot it: Extreme cases are obvious when you've had a student in the lab for the summer. Here again, as with the question of 'spine', they will usually self-select when given the experience of having a project and being told to work on it exclusively for 3 whole months (!).
Less extreme cases are harder to spot, but easier to treat. Sometimes they don't know it themselves until they're mostly done with graduate school and thoroughly sick of their thesis project. Vacations help. Meetings and positive feedback help. If they get through all of that and decide to stay in research, usually finding the right postdoc project will cure it. Again, most will self-select after grad school since they've had the experience and a glimpse of the road ahead: more long-term, delayed gratification projects.
6. Big picture, little picture. The best researchers understand that sometimes you can fudge it, and sometimes you can't. It's like the difference between stir fry and baking (respectively).
Ideally you want people who can grasp the big picture, but still pay attention to the little picture when it matters. You want someone who is meticulous, but you don't want the fantastic technician who doesn't see that she needs to be reading several journal articles a week now that she's in grad school.
How to spot it: This is the tricky one. I myself am not meticulous by nature but rather by training. I've worked with some who are meticulous by nature but who learned to appreciate the big picture during grad school.
The most successful researchers I know are big picture people who take care of the forest and hire little picture people to take care of the trees. Unfortunately most graduate schools are selecting on criteria (like grades and GRE scores) that have more to do with meticulously trimming the trees and nothing to do with locating the forest.
7. Politicians. I wasn't going to include this, but on second thought I think I should.
If you want your students to go on and be successful in academia, better to pick the ones who are charismatic, good at persuading others to do their work for them, good at self-promotion, and unlikely to burn bridges. You know the type I mean. And yes, you can spot them as undergraduates.