Yep, evolution is definitely fair game on the PCAT. You might be asked about different types of selection, for example, or the Hardy-Weinberg equilibrium. If you search online for the PCAT Test Blueprint and Sample Items, you'll see exactly what's tested on the PCAT, and this falls under the category of Diversity of Life Forms. Besides..."nothing in biology makes sense except in the light of evolution." - Theodosius Dobzhansky