the interaction of living things among each other exist in the process of eating and being eaten, wherein there are different kinds of relationships one is predation- which happens when an organism is eaten by another without processing it just like the rat and the snake. there is also parasitism-where parasite depends on a host for nutrition but parasite does not kill the host. there is also commensalism and other relationships.
the interaction of living things with the environment is on how and what living things do or care for it surroundings. just like improper disposal of garbage which is not right cause eventually this will come to us when it will cause clogging of drainage and might cause flooding