1. Cats are very sensitive to their interpersonal space.
Personal space can be thought of as a bubble of area around their bodies that cats consider their own. The bubble moves when the cat does, making personal space different from territory. Cats may become threatening if their personal space is invaded too quickly, especially individuals they aren’t very familiar with. This is a common reason for threats and fighting during introductions of new pets to the family.
2. Cats often do not have strict social hierarchies.
When cats live together, it’s often not clear who is in the dominant role in the relationship. Because cats usually don’t live in highly structured groups, they don’t always have well defined social roles. Instead, cats tend to allocate resources by sharing them. For example, one cat may have priority access to a window perch in the morning hours, while another has so in the afternoon.
3. Cats are subtle in their display of friendly, or affiliative behaviors.
Dogs are enthusiastic in their display of friendly behaviors. They jump on us, grovel, lick our faces and hands, whine, bark, cry and carry on. A friendly greeting from a cat may be a restrained rubbing up against our legs, and a meow. Cats tend not to throw themselves on us the way dogs do. Similarly their friendly and attachment behaviors with each other are also more restrained. For cats, resting in bodily contact with each other may be as friendly as it gets.
4. Once aroused into threatening behaviors, cats can remain so for quite a long time.
Those who work in veterinary clinics or animal shelters know that once cats become upset by being around other animals in the facility, they maintain these upset reactions sometimes for hours. This makes cats very difficult to handle, because they require quite a bit of calm down time to recover from these frightening events.