More aggressive during feeding time. More aggressive all the time it seems like. Some have exceptions, my female is the nicest one i own, but make sure you check your local and state laws because now i have to find away to get rid of my jampea dwarf male and my normal female. I hate the government. oh yeah and your feed bill will double, they'll be eating jumbo rats or small rabbits by the end of a year old, and soon after that will be taking jumbo rabbits or small pigs. But they are great pets when you take care of them and you get one with a nice temperement.