While many people like to cite humans as the only species who kill for no reason, we now know this to be a fallacy; it seems that primates in general do this. It’s not a sexist selection of primates, either; both male and female primates kill each other. Some even kill other primates’ babies out of spite. In fact, if you watch any type of documentary, such as Planet Earth, you’re bound to run across a species or two that uses violence to keep its subordinates in line. So maybe that violence is in our blood from the start.
We think that people act the way they do because of their personality. But what effect does their environment have on their behavior? We have all seen the same person act differently in different circumstances. Now a new study by Dutch scientists at Tilburg University in the Netherlands has suggested that a messy environment can cause people to stereotype other people.