1- Animals DO feel. Ever saw a dog "crying" after beying hit by a car? I did. I have 3 cats and 1 dog and they do feel if i acidentally step on them (wich almost never happens) so don't tell me they feel less or something like that.
2- As many of you said before, "Animals are lower life forms so they must not feel as much as we do. We may kill them as they don't suffer so much". [Sarcasm] Well, we must eat something, so why don't we eat mentally hill people?? I guess that it's a good idea as they don't feel as much as we do.. -.-" [/Sarcasm]
3- If we have the right to live, why don't they? Just because they have fur and maybe a tail? Well, if it's because they're different, I'm gonna start killing emo's for food.
4- Animal's do understand and some of them have 27% of the human capability of understanding what surrounds us and solving puzzles and such, wich is amazing for a "lower life form" as you said.
5- I would like to see you in an island filled with lions and bears, just to see you running arround, searching for any grass you could find to eat.