Studying Ecology Chapter 4 Section 1 Levels of Ecological Organization • Ecologists study life at many levels. • Ecology is the study of how organisms interact with each other and their environments . Individual Species Population Community Cells Tissue Organs Atoms Simple Molecules Macromolecules Ecosystem Biosphere Organ Systems Individual Species Organelles Cells Individual Species/Organism • Basic level of study for an ecologist is an individual organism. • Ecology describes the relationship between organisms and their environment. • A species is a group of individuals that… – interbreed and produce fertile offspring. – have genetic similarity Populations • Population: members of the same species that live in the same area at the same time. • The fleas living on your dog = a population. • All of the golden toads in the Costa Rican rainforest = a population. Communities • All of the populations in a particular area. • PA bears’ community includes: 1. 2. 3. 4. Plants and trees Other animals Fungus Stream life Ecosystems • An ecosystem includes all of the living things in an area AND their physical environment. • Back to the bears…Their ecosystem would including the following… 1. 2. 3. 4. 5. Air Trees Soil Nutrients Rivers Biosphere • All of the parts of Earth that host life. – all of the organisms and environments in which they live. • Ecologists rarely study this “grand” of a scale! Let’s Fill Out Our Diagram With Examples! Biotic vs. Abiotic Biotic Factors Abiotic Factors • Living parts of ecosystem or were “recently” alive. • Examples: leaves, trees, fallen logs, carrion (decomposing animals) • Ecosystem parts that have never been living. • Many are used or consumed by living things. • Examples: oxygen, sunlight, water, carbon. Habitat • The environment in which an organism lives • Includes all the resources needed to survive. • Include both abiotic and biotic factors, because both are required for living things to survive. Review Questions 1. Would all of the different kinds of organisms in a pond be considered a population or a community? Explain. 2. For each level of ecological organization (refer to your chart) state whether it contains only biotic factors, only abiotic factors, or both.