I guess right now I am unsure of how to properly ask my question. I have a column in the data.frame that I have changed from integer to a factor with 2 levels, Population 1 and Population 2. Each population has males and females and a number of parasites that was observed in each individual for each population. I have also changed the numbered individuals from an integer to a factor with multiple levels so that the individuals are categorical. I am wanting to isolate just one of the populations from the data.frame to work with, such as only Population 1 or only Population 2. The data.frame is pupfishB, is there something I can type in after pupfishB$POPULATION to further isolate the column to only Population 1 or Population 2? I am certainly not looking to get the work done for me as I need to learn how to use R effectively and efficiently. Thank you for your help.