I spit in a cup for science

Every year, the evolutionary genetics class does a little experiment to test whether humans can choose genetically compatible mates by smell. In real life, there are many other things that influence mate choosing, but historically we haven't always had online dating services and personal hygiene products.

Since the evolutionary genetics class is overrun with men, they needed some female volunteers (me). We spit in a cup, and the TA sequenced our DNA. Next we all must wear the same t-shirt to bed for 5 nights in a row, wash only with plain soap, and wear no deodorant or perfume. Our "natural smell" will be all over that t-shirt.

Then we smell each other's shirts and declare which smells the most appealing. Finally, they compare our DNA to see if each person's smell-choice is genetically compatible. Yay!