What is ecology? Ecology: study of interactions between organisms and their environment Ecoloy - definition

Ecological research Most ecologists use both qualitative and quantitative research. They obtain qualitative information by observing organisms. Ecological Research

Ecological research They obtain quantitative data by making measurements and carrying out controlled experiments in the field and in the laboratory. Ecological Research

The nonliving environment: Abiotic factors Abiotic factors: Non-living parts of the environment Examples: wind, temperature, moisture, light, and soil. Abiotic factors

The nonliving environment: Abiotic factors Ecology includes the study of features of the environment that are not living because these features are part of an organism’s life. Abiotic factors have obvious effects on living things and often determine which species survive in a particular environment. Abiotic factors

The living environment: Biotic factors A key consideration of ecology is that living organisms affect other living organisms. Biotic factors: Living organisms in an environment Examples: plants, animals, fungi, protists, bacteria Biotic factors

Biotic and abiotic factors form ecosystems Ecosystem: interacting populations in a biological community and the community’s abiotic factors. There are two major kinds of ecosystems— terrestrial ecosystems aquatic ecosystems. Ecosytems

Ecosystem Ecosystem

Other Sites for Ecosystems Terrestrial Ecosystems Biotic and abiotic factors form ecosystems Table 2.1 Examples of Ecosystems Aquatic Ecosystems Other Sites for Ecosystems Terrestrial Ecosystems Forest Old farm field Meadow Yard Garden plot Empty lot Compost heap Volcano site Rotting log Freshwater Pond Lake Stream Estuary Salt water (marine) Ocean Aquarium Human body Skin Intestine Mouth Buildings Mold in walls, floors, or basement Ventilation systems Bathrooms Food Any moldy food Refrigerator Example ecosystems

Organisms in Ecosystems Habitat: the place where an organism lives Ex: pond for a beaver; tree for bark insects Habitat

Organisms in Ecosystems Habitats can change, and even disappear. Habitats can change due to both natural and human causes. Habitat

Niche Niche: the role or position a species has in its environment (job) Ex: owls control rodent population at night Niche

Symbiosis Symbiosis: A relationship in which there is a close, permanent association between organisms of different species Symbiosis means living together. Three kinds of symbiosis are recognized: mutualism, commensalism, and parasitism. Symbiosis

Mutualism Mutualism: both species benefit Ex: bacteria in our gut

Commensalism Commensalism: one species benefits and the other species is unaffected Ex: barnacles on a whale Commensalism

Parasitism Parasitism: one species benefits and another is harmed

Parasitism Parasites have evolved in such a way that they harm, but usually do not kill the host species. Ex: tapeworm Parasitism

Question 1 The study of interactions that take place between organisms and their environment is __________. A. abiosis B. symbiosis C. ecology D. biology Section 1 Check

The answer is C. Ecology is a branch of biology that developed from natural history. Section 1 Check

Question 3 Which of the following is a biotic factor? A. moisture B. soil C. earthworm D. light Section 1 Check

The answer is C. Biotic factors are all the living organisms that inhabit an environment. Section 1 Check

Question 4 A(n) __________ is a group of organisms, all of the same species, which interbreed and live in the same place at the same time. A. biological community B. population C. ecosystem D. habitat Section 1 Check

The answer is B. Communities and ecosystems are comprised of more than one species. Habitat refers to the place an organism lives. Section 1 Check