the branch of biology that deals with the relations of organisms to one another and to their physical surroundings.

a group of interdependent organisms of different species growing or living together in a specified habitat.

a biological community of interacting organisms and their physical environment.

an organism that derives the organic compounds and energy it needs from the consumption of other organisms

an animal that feeds on plants.

An animal that feeds on meat and other animals

system of interlocking and interdependent food chains.

hierarchical series of organisms each dependent on the next as a source of food.

An organism at the topmost level of the food chain