It is sometimes suggested that the cat is not a naturally sociable animal, which may come as a surprise to many cat owners! Cats hunt on their own and prefer to defend themselves individually and so they are sometimes falsely accused of being loners. However, in a wild setting, cats tend to form organised hierarchies and there is clear evidence of social behaviours in their relationships with humans and other cats in a domestic setting.
It is important to remember, however, that cats are naturally expert hunters. If your cat feels threatened and cornered he may lash out with his claws or deliver a more intentional bite. In particular, nursing cats should be treated with great respect and given plenty of space as their desire to protect their kittens can make a previously mellow cat react with much greater aggression.
Other strange behaviours
In the wild, a subordinate cat will often bury its poo in order to hide its presence from the dominant cats in the area. so as not to demonstrate its presence to more dominant cats. An alpha cat will leave their poo uncovered because they are confident of their dominance and wish to assert ownership of their territory. Domestic cats also take on this behaviour and in a household with only one cat the cat may well bury his poo as he feels that his human companion is dominant. If there is more than one cat in the household, there may be an obviously dominant cat and an obviously subordinate cat, or all cats may consider themselves to be dominant or subordinate!
When your cat screws up his face and curls his lips back show his upper and lower teeth this is known as Flehmening. He does this in order to get more information about a smell he has discovered by allowing the smell to register with "Jackobsens Organ". This organ is located in the roof of his mouth and is also associated with appetitive and sexual behaviour. In the wild, Flehmening is quite pronounced (and is not by any means limited to cats) but domestic cats rarely use this technique and when they do it tends to be less dramatic.