Rabbits bounding across fields looking for a mate. Once found they'd spawn ten rabbits and those would go off to spawn 100 more.

what about animals stalking you think about your follow a herd of deer. you sneak up a close as you can then you pull back your bow and are about to let fly. when you hear a growl or are struck from behind by a wolf or sabertooth tiger. i think its a little more realistic. example 2 your walking through the forest at night and you hear twigs crack behind you you turn around and nothings there so you continue on you hear it again but this time it's closer. you turn again to see nothing you continue on only now your in full flight for your life. you turn a corner and run right into a saber tooth tiger the one you were being herded towards. like lions of today do