Compléter ecosystemsVersion en ligne grade 8 natural sciences par lizzy west 1 ecology interaction community ecosystem community Look again at the illustration of wildlife in a game reserve . There is between the different populations to form a . If we now study the communities' interaction with the non - living things in their environment , then we are studying at the ecosystem level . Think of the different populations of organisms that form a in the Kruger National Park , such as zebras , elephants , lions , springboks , different types of trees and grasses . Now look at this photo of some of these populations at a watering hole . In this photo , we study the interaction between the living organisms and the non - living environment . As an example , the zebra and springbok drink water , while the elephant pours mud over itself to cool off . It is an . 2 ecologist environment ecology organism organisms Every living on Earth depends on , and interacts with , other living and non - living things to survive . For example , organisms depend on other for food and depend on their for protection and shelter . This particular branch of the sciences that studies the interaction of organisms with other organisms and their environment is called . A person who studies these relationships and interactions is called an . 3 biosphere populations community ecosystem biosphere ecological populations The interactions that take place in a specific area are usually divided into four levels : , communities , ecosystems and the Individuals live together in . Different populations collectively form a . Communities , together with the non - living things in their environment , form an . All the ecosystems on earth are called the .