Just a normal guy with a highschool diploma here so forgive me if I don't make any sense. In your opinion, how do you think time relates to the size of the being? Instead of thinking about time as night and day, think about it maybe in heartbeats, or steps taken, or breaths. It seems that the larger an animal is, the longer it lives. Do you think that a fruit fly, measuring its time by heartbeats, or how many times it flaps its wings, could live as long a life as we do? This was just an errant thought that crossed my mind, your opinions would be greatly appreciated. Perhaps the theory of relative motion doesn't have so much to do with speed as it does the size of the object travelling.