Mr. Serenata is like that to a degree (not quite to the extent as the OP, but still…). He relates much better to animals, empathizes with them more than people, etc. When talking to his parents, they said he was always closer to the family pets than people. He could spend hours each day playing with the dog, and he admitted he cried hard when their first family dog died. He barely shed a tear when his grandma (who he was close to) died.
I don’t want to imagine what will happen when our hamster Smores dies. She’s been sick lately and I know when she dies, it’ll crush him.
I’m more upset/concerned when I see a person who’s hurt or ill than an animal. Especially if it’s a kid. But on the other hand, it really, really bothered me when we had to dissect a rat for biology in high school, yet when I have labs with human cadavers my response is “That’s so cool! You can see all the bits!”. I think it’s because I know that no-one (in this society) would ever let a person die just because some anatomy students needed to study - the people died naturally and wanted their bodies to be used this way. But no-one cares about the lives of lab animals, so I can’t help but feel for them.
Eh, humans are animals too. Any distinctions we make between the two groups are really just an artificial construct based on humanity’s need to feel special.
In my view, though, dolphins, chimps, etc. are no better or worse than we are (not innocent, not evil - just another creature trying to survive).
I can relate to the OP, and it definitely has to do with helplessness and vulnerability, and it extends to child abuse as well. Children, especially young ones, are in helpless situations the same as animals.