All animals have their own personalities, and you can't tell me that I'm anthromorphizing them. Well, maybe I do to a point, but that doesn't mean that they don't have their own personalities. Every animal I've ever known has had a different personality, and would react to different situations differently - they are just as unique as human beings are. For example, my current horde.
Charlotte is somewhat grumpy, bossy, and no-nonsense, but loves it when I hug her, and can almost always be made to purr when you scratch her behind the ears just right. She makes demands, and fully expects that everyone, feline, canine, and human alike will obey them. And what do you know, it often turns out that way...
Compare her to Annie, who has actually done a bit of a metamorphosis in the year and change that we've had her. Annie started out as very shy and mostly afraid of people, and has turned into... something bolder. She demands attention constantly, crying loudly and trying to put herself in between me and Argos. She insists on having what the other cats are having, even if she doesn't really want it. She loves soft, warm places throughout the house, and is content with her lot in life.
And then compare THAT with Bit. Bit is a shy one - and seems to get even more shy as she gets older. I used to be able to count on her coming downstairs to charm our guests, but anymore, if there are guests, she is probably hiding upstairs. But when it's just me and Jeff in the house, she will come in, whirring loudly, demanding attention. But when you try to give it to her, she runs away, looking over her shoulder to see if you'll chase her. She likes to be approached softly, and still has a playful streak, which sometimes manifests itself in shredded toilet paper, or my fuzzy house socks turning up in odd places throughout the house.
And of course, compare ALL of those with Argos. Of course, he is a dog, and is therefore going to be different than a cat. He has a mostly calm and steadfast personality, preferring to sleep on the couch or the dog beds (plural because we have one upstairs and one downstairs) to playing or causing a ruckus. However, he gets positively excited when he sees Jeff or I after a separation from him, even if we only went upstairs for a few minutes. He dances and spins and cavorts around like he was just told that it was Christmas and his birthday all in one day.
I love all of our animals, and love seeing how their personalities manifest day after day. It's also fun to be able to shape them - maybe not their personalities so much, but certainly we affect how they react to the world, and in whether or not they feel secure enough to be themselves.