Biodiversity

Objectives: To explain the process of evolution by natural selection To define adaptation

Evolution-change in the genetic makeup of populations over time based on Charles Darwin’s theory of natural selection natural selection is the mechanism through which evolution occurs

Darwin’s Theory of Natural Selection 1) Variation exists among individuals of a population. 2) Some variation is inherited. 3) Populations tend to produce more offspring than the environment can support.

Darwin’s Theory of Natural Selection (Continued) * 4) Organisms that are best adapted to the environment will survive and reproduce (“survival of the fittest”)

Adaptation-an inherited trait that increases an organism’s chance of survival and reproduction in a particular environment

Examples of Adaptations

Over time, an adaptation will appear in a greater proportion of the population. Eventually, through the process of evolution by natural selection, the adaptation will spread throughout the entire population.

Example of Natural Selection peppered moth (Biston betularia)

Objectives: To define biodiversity To explain ways in which biodiversity is important to ecosystems and humans

Biodiversity-the number and variety of different species in a given area only 1.7 million of the estimated 10-30 million species believed to exist on Earth have been discovered

Benefits of Biodiversity 1) species are connected to ecosystems each species plays an important role in an ecosystem every species is either dependent on or depended upon by at least one other species

keystone species – a species that is critical to the functioning of the ecosystem in which it lives example – sea otter

2) population survival genetic variation increases the chances that some members of a population may survive environmental pressures or changes

3) medical uses 75-80% of the world’s population uses medicines made almost exclusively from plants about ¼ of prescription drugs contain ingredients derived from plants Pacific yew

4) industrial uses undiscovered and poorly studied species represent a source of potential products for industry

5) agricultural uses most crops produced around the world originated from a few areas of high biodiversity maize

6) ethics, aesthetics, and recreation ecotourism – form of tourism that supports the conservation and sustainable development of ecologically unique areas

Objectives: To differentiate between endemic, threatened, endangered, and extinct species To list characteristics of species most prone to extinction

endemic species-a species that is native to a particular area and that is found only there lemur (Madagascar)

threatened species-a species that has been identified to become endangered in the foreseeable future American alligator

endangered species-a species that is likely to become extinct if protective measures are not taken immediately Karner blue butterfly African elephant

extinct species-no longer found alive golden toad

Characteristics of species most prone to extinction 1) wide-ranging species require large blocks of habitat to maintain viable populations Florida panther

2) migratory species need habitat and resources in different ecological regions at different times of the year for their survival Golden-cheeked warbler

3) habitat and resource specialists require protection of very specific habitat types or resources koala

4) narrow-range endemic species populations are small and confined to limited geographic areas golden lion tamarin

5) heavily exploited species have high commercial value rhinoceros

Objective: To list and explain the major threats to biodiversity

Major Threats to Biodiversity habitat destruction and fragmentation use of land by human populations destroys and fragments habitats of other species major cause of current extinctions only about 70 adult panthers remain in Florida

2) invasive exotic species exotic species – species that is not native to a particular region threaten native species that have no natural defenses against them gypsy moth

3) harvesting, hunting, and poaching poaching – illegal hunting, fishing, or harvesting of wildlife

4) pollution pesticides, cleaning agents, drugs, and other chemicals used by humans make their way into food webs

Objectives: To list and describe the types of efforts to save individual species To explain the advantages of protecting entire ecosystems rather than individual species

Methods of Preserving Individual Species captive-breeding programs involve breeding species in captivity, with the hope of reintroducing populations to their natural habitats California condor

2) preserving genetic material germplasm-genetic material contained in the protoplasm of germ cells stored in germplasm banks for future use in research or species-recovery efforts stored as seeds, sperm, eggs, or pure DNA

3) zoos, aquariums, parks, gardens house the few remaining members of certain species living museums of the world’s biodiversity

The most effective way to save species is to protect entire ecosystems rather than individual species. may allow most of the species in an ecosystem to be saved instead of only the ones that have been identified as endangered

Objectives: To explain the purpose of the Endangered Species Act To describe the main provisions of the Endangered Species Act

Endangered Species Act passed by the U.S. Congress in 1973 protects any plant or animal species in danger of extinction amended in 1978, 1982, and 1988

Major Provisions of the Endangered Species Act 1) The U.S. Fish and Wildlife Service (USFWS) must compile a list of all endangered and threatened species in the United States.

2) Listed species are protected from human harm. prohibits “taking” (includes killing, capturing, harming, harassing) of a listed species “taking” also includes habitat alteration resulting in harm to a listed species anyone who harms, buys, or sells parts of these species is subject to a fine

3) The federal government may not carry out any project that jeopardizes a listed species. designates “critical habitat” prevents reduction or destruction of habitat

4) The U.S. Fish and Wildlife Service must prepare a species recovery plan for each listed species. plans propose to protect or restore habitat for each species

habitat conservation plan-plan that attempts to protect threatened or endangered species across large areas of land through trade-offs or cooperative agreements

Objective: To describe worldwide efforts to prevent extinctions

International Union for the Conservation of Nature and Natural Resources (IUCN)-facilitates efforts to protect species and habitats at the global level publishes Red Lists of species in danger of extinction around the world advises governments on ways to manage their natural resources sponsors conservation projects

Worldwide Efforts to Prevent Extinctions 1) CITES (Convention on International Trade in Endangered Species)

international treaty whose aim is to regulate international commercial wildlife trade so as not to be detrimental to the survival of the species (prevent poaching)

2) Biodiversity Treaty goal is to preserve biodiversity and ensure the sustainable and fair use of genetic resources in all countries result of the first Earth Summit in Rio de Janeiro, Brazil in 1992

3) Private Conservation Efforts Many private organizations work to protect species worldwide. often more effective than government agencies

examples of private organizations a) World Wildlife Fund b) Nature Conservancy c) Conservation International d) Greenpeace