text: if humans have evolved from monkeys, then why haven't all monkeys changed?   we didn't evolve from monkies... humans and monkies/apes... evolved from a common ancestor... its a bit more complex then how i am putting it but trying to give the general idea... our common ancestor given different enviromental conditions and different places it was located had different traits that the enviroment selected for... some died... some lived... over time we get a number of different species, us being one, monkies and apes being other forms...