Having two PIs as mentors

[MEB05]

One of the PIs who I have been in contact with suggested that I do one of my rotations with a collaborator of his. He mentioned that they are potentially looking to co-mentor a student so that the student could gain the advantage of being trained in the two approaches their labs take to the same area of research.

It sounds like an interesting idea in that I would be able to learn a wider variety of techniques, and potentially have more publication opportunities. I haven't seen this in my experience, is it at all common, or at least not unheard of? Are there any big drawbacks I should consider?

[jayeyesee]

A graduate student in my lab is pretty much in that situation. She is being mentored by two PIs and splits her time between the two labs (it really doesn't help that the labs are so far from each other). As you can imagine, the rewards can be great (more opportunities for publications, growth as a scientist, etc...) but the drawbacks are nothing to scoff at. Long hours, overwhelming expectations, two PIs to please, etc... I really do feel the graduate student is being pulled in every direction possible but she seems to be doing okay. Heck, she might even get out earlier with all the data she is producing lol.

[virion]

I do this. Though most of the work is collaborative (shared projects, though with each being spearheaded and thus found more important/interesting by one particular PI). You definitely learn not only different techniques, but different outlooks on science/the scientific process. I can see exactly how it could go to hell, though. Fortunately, the worst things come to for me are having a PI say something along the lines of, "Oh, he's having you do that? Well, don't be surprised if you find that you've wasted a significant amount of time there." It's easy for me to keep a good grip on which experiments are high and lower priorities for each of them, so it's not really a problem. I do know people, though, who will have one PI essentially forbid them from doing what the other is asking of them. Not a nice situation to be in.

If the two don't work together, you're going to need to figure out how you're going to balance yourself. As jayeyesee says, you might get pulled in several directions which lead to some great output. Or you could simply be pulled apart.

[BassAZ]

I'm also in the same situation. It's nice because I'm the bridge between the two researchers: my main PI works mainly with gut microbes and focuses mainly on the host-side of things whereas my other one works on the bugs side of the science. I'm working in similar things but looking at lung pathogens.My main boss likes to describe me as the child of a divorced couple: I live with mom but I spend some weeks with dad. (Not to make light of divorce - it's a good analogy though).

The BIGGEST thing I can see is that you're using these two as resources to help your networking as well. Obviously they have to talk to one another about the directions that you are taking your research/they're suggesting you take. But as science gets more and more collaborative, it's an excellent way to learn to work with multiple people. It's also convenient if anything comes of your research because there's a natural possibility for a PPG or other collaborative money efforts.

I also know some people treat having a co-graduate student as a feudal marriage; that is, to show the powers-that-be there is peace between the two labs, they say "Look, we share this student! We must be friends!". It's subtle but some people really do think about the politics of grant writing, etc.

As was said earlier, make sure these two talk normally - you don't want to have someone feel left out. You also want to make sure they have a strong collaboration between each other - you don't want to be caught in any pissing matches. I haven't experienced anything bad thus far, so those are the only pitfalls I've looked at for now.

[Eigen]

Make sure you ask around. I do have a friend that's working between two labs, and she runs into the problem that both professors seem to assume that if she's not working in their lab, she's not working- and it's leading her to work almost double the hours of anyone else in either of her individual groups.

On the other hand, I know several other professors that I feel could very readily co-mentor me with my current PI without it turning into a "who's lab are you in most" competition.

[GradStudentY3]

Been there, done that, got the T-shirt.

A few months in, my co-mentors broke up with each other over grant-related issues. They were best friends who had collaborated for a few years before I joined the labs. But things happened, and all of a sudden, they weren't speaking anymore. My project had to be abandoned by both PIs as neither has the resources to do it alone. Then came the campaign of "Join my lab - not his - and do a different project with me" from both sides. It got very complicated, and eventually, I had to switch lab all together.

Sadly, my experience was not that uncommon either. Long-term collaborations require a lot more than just a common project.