Do humans have a greater right to live than other animals? If so, would beings of much greater intelligence and perception hold that same right over humans?

I am not a vegetarian but I think I should be. I would not couch the issue in rights language but putting animals through suffering just so I can have my New York Strip Steak just seems wrong to me. Given human history, I cannot imagine what kind of arguments we humans could muster if aliens came down and proposed to us as a food source.