if an organism dies then the population of that organism will decrease
corpse is dead_organism. dead_person is not dead_organism. dead_bird is dead_organism. corpse is not dead_organism. dead_insect is dead_organism. dead_bird is not dead_organism. dead_living_organism is not dead_organism. dead_insect is not dead_organism. dead_person is dead_organism. dead_living_organism is dead_organism.