The Ecosystem Describe the structure of an ecosystem. Relate the concept of habitat destruction to the loss of biodiversity. Apply an understanding of how human decisions and activities can result in habitat destruction and a loss of biodiversity
Species • An Ecosystem is a highly organized, structured environment in which all parts exist in a delicate balance. • The structure and function of ecosystems can be studied at many levels, from individual species to the entire ecosystem.
Species • A species is a group of organisms so similar to one another that they can breed and produce fertile offspring. All members of a species have similar needs, such as the range of climate tolerance, size of territory, and types of food. Species do not compete with one another for resources.
Species • The specific environment in which a particular species lives is its habitat. For example, the tops of the trees in a pine forest may be the habitat of a species of bird. • Within their habitats, individual organisms find the appropriate food, shelter, temperatures, and other factors needed to survive. The destruction of habitat is a serious threat to the survival of many species.
Species • The total area in which a species can live is called its geographical range. • The size of the geographical range depends on the availability of suitable habitat. For example, the mountain lion requires a habitat with diverse plant life, a large hunting territory, and a variety of prey animals.
Species • The U.S. Congress passed the Endangered Species Act of 1973 to protect disappearing wildlife. Twenty years later, there were 278 species of animals and 298 species of plants listed as endangered in the United States. There are more than 1 million species worldwide known to be endangered.
Populations and Communities • All the members of a species that live in the same geographic area make up a population. • Populations do not live alone in their environment. In any region, many different populations share the same living space, although each one uses different aspects of the environment. • All the different populations that live and interact in the same area make up a community.
Ecosystems • An ecosystem includes all the communities in an area, as well as the abiotic factors in the environment. • The variety of species in an ecosystem is known as biodiversity. • If enough of a particular type of habitat is destroyed, the species that live in the habitat can die out completely, or become extinct. When species become extinct, biodiversity and stability of an ecosystem are reduced.
Homework 3.3 • What factors are included in an ecosystem? • What is the difference between a territory and geographical range? • Provide at least one endangered species of the US. State the reason why it is on the endangered species list. 3b. Provide at least one endangered species worldwide other than the US. State the reason why it is on the endangered species list.