Rats are highly intelligent and adaptable animals. They are known as commensal rodents because of their ability to live in human environments like cities, suburbs, and rural areas. They will travel long distances throughout their environment in order to find food sources and nesting sites. They also learn their environments well, well enough that they become wary of unfamiliar things in that environment. This makes them difficult to trap and remove.
Many species of rats live in groups or colonies. Within these groups, they establish a hierarchy within these groups where dominants and subordinates are strictly defined. Subordinates and dominants have defined places within the group or colony. When females are entering estrus and ready to mate, they will mate with multiple males. They will mate with the dominant ones first and then down through the hierarchy. This is an example of the roles of different individuals within the group.
Rats are not inherently aggressive, but they will defend themselves and they’re young if necessary. They will demonstrate certain behaviors when they are cornered or feel threatened. They will fight, chase, box, and bite in order to defend themselves. They also show various defensive posturing like sidling and belly-up postures.