I think I saw it once, too.<quoted text>
There is a division in NASA that specializes in postulating that if there would be macro life on a certain planet, what it would look like. For example, in Jupiter, a macro organism would be like an air baloon constantly rising and falling upon different temperatures. I saw that on natgeo once.
I'm not sure how reasonable such postulations are though.
Do you think Optimus Prime could be out there somewhere?
Thing is, it is impossible to say. Macro organisms function within a food chain. There must be a base food source (on earth it is plankton, grass and shrubs). Herbivora eats the grass and gets hunted by carnivora.
Now, Population dynamics show that there is a relationship between herbivora and carnivora. If herbivores are defenceless against carnivores, they all get eaten and die out. However, if they are too well defended, carnivores die out.
For this reason there is an evolutionary (for want of a better term, I will call it "mechanism") mechanism we call "The Red Queen".
Ever watch Alice in Wonderland? Where the Red Queen tells Alice that no matter how fast she runs, she will stay in the same place. How this applies to evolution, is that yes, herbivores evolve defences, but carnivores evolve brains, cunning, teeth and claws. And somehow this is perpetuated throughout the fossil record.
Think Lions and Buffalo. Think Great White Shark and Fur Seal. Tyrannosaurus Rex and Triceratops. Allosaurus and Stegosaurus.
And the defences vary. Sone animals like gazelle evolved to be very fast and agile. Some herbivkres, like mice, breed by the thousands (so a single kill does not hurt the population). Triceratops evolved into arguably the most dangerous animal ever to walk on land. Parasauralophus involved infrasound and could warn other memebers over many miles, Giant Sauropods just grew too damn big to be killed. Even cows, chicken and sheel - they grew easy to domesticate. Humans kill them by the million, but they are bred by the billion.
Niw, for every change a herbivore undergoes, a carnivore needs to go through changes to counteract that. Leopards evolved ambush technique. Human beings evolved to be smart enough to build tools to hunt. T-Rex evolved giant jaws and banana shaped teeth. Lions evolved to be smart, fast, agile and powerful.
All the while, keeping that balance.
How is this relevant to the discussion? That we cannot possibly know what mechanisms or behaviour extra terrestrial employ to either kill prey, or fight off predators