I’m not 100% sure if this is a scientific theory but I’m going with the big bang theory. The big bang theory is a scientist best guess on how the world came to be. A 2013 map of the background radiation left over from the Big Bang, taken by the ESA's Planck spacecraft, captured the oldest light in the universe. This information helps astronomers determine the age of the universe.
Parasite: Parasites are different from predators because parasites only take resources from one host, whereas predators eat many prey. A good example of this is the trematode parasite Schistosoma mansoni. An adult schistosome parasite lives inside of just one human host
Be sessile (move from place to place very slowly, or not move at all)
D: Surface-water runoff from rain