It seems that animals have personalities too.  There is a new field of research opening up in animal studies that studies animal personality.  This field used to be looked upon lightly since most scientists believed that referring to animals having personalities was anthropomorphic, or that people were applying human characteristics to animals.   One scientist recently showed how very simple animal personalities work in nature, leading the way to perhaps further evidence that animals have more complicated personalities. Franz Weissing of the University of Groningen of the Netherlands studies animal personalities and he has found that animals in group can have both rigid and flexible personalities.  Plus, having a healthy mix of both in each group is actually beneficial.  So, it's not always a good idea to have an entire group of open minded animals or close minded animals.   Weissing also works at the Santa Fe Institute and he ran some experiments on ducks, along with his colleagues.  They went to a duck pond twice a day and placed bread along the right side of the pond.  Eventually the ducks learned to associate the right side of the pond with more food and would hang out there while foraging.   One day, they switched up the experiment and placed the bread along the left side of the pond.  Many of the ducks continued going to the right side of the pond to forage even though there was less food.  They just associated that side of the pond with more food.  However, a few of the ducks had been checking out the other side of the pond all along, just in case.  When they noticed the bread in a different place they swam over and pigged out. The ducks that had been checking out other areas of the pond all along were more open minded.  They were the flexible animals in the group and open mindedness is a definite personality trait.  While the other ducks that remained on one side of the pond were more rigid.  You could say that they were patient or just stubborn, but they stayed on the right side of the pond just in case future food showed up because of their past experience with the bread.   This sort of trait is good for both groups.  The flexible animals got to pig out on new sources of food first, while the rigid ducks were able to eat what little bread remained on their side of the pond with less competition.  This also seems to indicate, to me at least, that personalities are result of natural selection. Source: http://news.yahoo.com/s/livescience/20081010/sc_livescience/animalshavepersonalitiestoo;_ylt=AspzXWlqPs6eul.dJHeL2Ah4hMgF