Either way, it still spells something about how the human mind works. If there were two incoming accidents, who would you save? The attractive opposite of your gender, or a guy who may be developing a cure for cancer (you would not know) but is not your fancy? This goes for animals as well. Would you save a cute puppy or an older dog which is less than desirable (as a pet) but helps blind people live out their day? Perplexing.
I didn't know we were actually being serious here.
Sympathy isn't about saving someone's life who is in immediate danger. I can hate someone, having no sympathy for them, but I'm going to save their life if they're in danger. In life threatening situations you have to assess who is in the most immediate danger and save that person. All things being equal, I'm not convinced beauty/ugliness plays a role at all in a such crisis situation. I guess it's interesting to ponder though.
Most domesticated animals can't fend for themselves as well as humans can. We also sympathize with a dog more often because dogs often to always give unconditional affection/love. This is key here. They just happen to be cute to many people. Cuteness was bred into dogs, or at the very least was a product of their domestication/breeding. We made them the way they are.
Are a pack of wolves cute?
On another note, in life threatening situations, females and children are always put to safety first. The reasons are obvious and have nothing to do with beauty.