To let you do something
Some people believe that a cat can learn to Meow at a human to let him do something such as bringing food. Those people claim that cats Meow when a human fails to understand their body language or the messages they are trying to send to a human.
A cat can Meow if it feels pain. Some medical conditions result in excessive meowing. In such a case the cat has to be checked by a veterinarian.
Some cats can meow if they wanted more attention from their owners or if they felt like they want to play.
Cats can Meow when they feel anxious. This can happen when their surroundings change or when they are taken to new places.
To signal for a mate
Females Cats can Meow when they are ready for mating to Signal male cats. (See Why Do Cats Love Catnip?)
Cats Can Meow when they are hungry. Some cats learned to Meow when they see their plates empty. Meowing in such a case can be a demand for humans to feed them.
As cats get old their cognitive functions weaken and can Meow a lot for no reason.
New cat in the Neighborhood
A cat can Meow more often if a new cat appeared in the Neighborhood. This can be either a sign of happiness or dissatisfaction.
Just saying Hi
A cat can Meow just to say Hi or make its presence clear.
Kittens ask for help
Kittens Meow to their mothers when they feel cold or hungry. After they grow up they usually stop Meowing to other cats.
To get in or out
Cats can Meow if they want to be moved in or out of a place. It’s their way of getting human attention to their need. (See Why do Cats always land on their feet?)
Cats can Meow to complain to humans about something that has happened. For example giving the cat a food that it doesn’t like can result in Meowing.
Cats do feel lonely as well. If the cat spends too much time alone then it can Meow out of loneliness.
Meowing varies by breed
Some Cat Breeds Meow much more than others. Siamese cats for example are known for excessive Meowing.
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