Is it okay to discuss both interests, which aren't closely related, in my statement? Is it possible to study both in grad school? The schools I am applying to - and my first choice - would be matches in both areas.
Or should I focus on one.
You may get differing opinions on this; however, note that in graduate school, you will (almost certainly) work with
one primary mentor. Unless you can develop a way to link the interests into a single project viable for that mentor's lab, you'll probably have to localize your work in one of those interests as you complete grad school.
That said, there are probably pros and cons for either approach in your statement. If you single out one interest, you can devote your
entire statement to that interest and thereby (perhaps) make the more compelling case for why you're a good fit for that school. The downside is that your app may be passed over by the prof specializing in the other subject of interest to you. Conversely, you
may seem less focused if you discuss both interests; however, with some skill, you may be able to present just enough of a convincing argument for your goodness of fit in either lab. Thus, if one prof passes over your app, the other might snag it. The overarching thing to consider is that you have only so many words available (roughly 500-1000 for most schools) and that you want to make the most compelling, undeniable case for your qualifications as you can.
I had an English professor review my statement; she gave me the best advice I've ever received:
every sentence, every word, should add up to produce an undeniable conclusion that you are the student they need for their program. That means no fluff, no tangents, etc. Every point you make should be directly relevant to why you'd work well in the lab(s) in which you want to work.
I've just been accepted to two or three strong schools for the fall '11 semester, so this is all pretty fresh for me. And honestly, I'm assuming you've been working with a prof on some research, so you may want to ask him/her!
😀 Good luck with apps! I had no idea this website existed when I applied!