
Most research programs require some kind of essay, which I tend to call a "personal statement." Aaron noted that most of the applicants to his program wrote completely generic personal statements, and gave no indication of why they wanted to be in that particular program.
By saying something like, "I want to be in your program, because I see it focuses on bee research, and I have been fascinated by bees since I read this paper by Dr. Jones...", you might get yourself past the first cut of applications.