<p>I have worked in a lab for 2 semesters. My work was closely supervised by the research scientist at the lab. The professor was present at the lab the majority of the time I was there. </p>
<p>The research scientist said he's very happy to write a LOR for me. Would the adcom view this in a weird way? Would they wonder why a professor didn't write the LOR? If so, would that hurt me? Could they also contact the professor later on or would they only contact the writer of the LOR (research scientist) if they have questions? </p>
<p>Also, for research projects, I don't think an undergraduate student necessarily have to be supervised by a professor. Thus, IMO, I do not think it would look weird. </p>
<p>I know some will suggest that the research scientist can write the LOR and then the prof can sign it, but this will most likely not be the case for me.</p>
<p>Yes, the research scientist can write the recommendation letter. It won’t be as strong as a letter from the professor, but I think admissions committee members will understand that many undergraduates are directly supervised by a postdoc or a research scientist as opposed to a professor (and often have that set-up in their own labs).</p>
<p>Could they contact the professor later? Of course, and they may. It depends on them and their preferences.</p>
<p>Why don’t you just get LORs from both? I submitted an extra LOR every time there was an opportunity to do so. My P.I. wrote mine, but I have heard of postdocs writing them.</p>
<p>My P.I. literally never goes in the lab either, but I got to know him through taking one of his classes, lab meetings (and going out after), conference travel, and making appointments to talk to him about my research interests and future plans. I felt like it helped me to have my P.I., who is well-established and recognized within his field, write me a strong LOR. So basically my answer is the same as juillet’s.</p>