Domestic cats are scared of one thing: being attacked by a predator. This fear can be shown in a wide range of circumstances which might mask the root cause of the behaviour. This fundamental and completely instinctive fear of failing to survive is inherited from the domestic cat’s wild ancestor.
If a cat becomes fearful in a home that is not calm and friendly because the owners are not good at cat caretaking the underlying fear comes from a possible threat to the cat which the cat instinctive believes may cause harm.
If a cat is scared of some sounds like heavy footfalls outside which is a legacy of a bad experience from years ago, once again this is because the cat is scared about being harmed.
The classic object that domestic cats are scared of are cucumbers placed behind them. There are many videos of this. The cat turns and sees a cucumber on the ground and they jump a mile to get away. People find this amusing. Cats are scared to death of a cucumber because they don’t recognise the object as something passive and safe because they haven’t seen it before. Therefore they are instinctive scared that it might be dangerous. They think it might attack them and cause injury and death.
Strangers entering the front door scares a lot of domestic cats. The reason is obviously the same: the stranger is potentially a hostile predator which they have get away from in the first instance and hide. Then they check out the stranger. It is an act of caution to protect themselves. They are scared because they see a potential attack by a predator.
Not all cats are scared of strangers. These are confident, well socialised cats. But their relaxed attitude towards strangers comes from experience. They have learned that strangers coming into the home are not hostile predators but safe. It is a learned process which overrides the innate instinct.
Scared rescue cats in a cage in a rescue center are scared because they think they are going to be harmed by the workers at the center. It is a hostile, strange environment where the cat instinctively feels that they could be harmed which might jeopardise survival.
I believe that you can explain all scared behavior from domestic cats with the same argument.
These are my thoughts alone without references to books or the internet. I am fully open to counterarguments and different ideas which I’d like you to share in comments, please.
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