The social position of an animal within a group, whether within one species group or mixed groups, allows one to discern different levels of dominance. These are often called hierarchies or peck orders after studies initially done with domestic chickens. The following identify different behavioral associations.

BIOLOGICAL RANK

Biological rank exists, when a dominance exists between different species, which compete for food, water or space. It implies a situation where the competitors try to avoid each other. The species of lower rank gives way to the dominant species so flights are rare and the dominion species has preference over feeding places and occupancy sites. Examples from the wild include gorilla over chimpanzee, brown bear over black bear or Uinta Chipmunk over Colorado Chipmunk. This may result in a unique situation in zoos when various species not normally associated in the wild are exhibited together. Several years ago a few bison were fatally injured when they were penned with mountain goats that stabbed the bison in the abdomen with their stiletto like horns. A zookeeper must detect a developing biological rank system and ensure all the animals in an exhibit have access to food, water, shelter and a resting-place and are protected from injury.