Bio-diversity• Bio refers to things

that are living.• Diversity refers to

variety.• Biodiversity refers to

the variety of life in an ecosystem

Which of these would have greater biodiversity?

Biodiversity By Location

• The closer a location is to the equator, the greater the biodiversity. Q:Why?

• A: Because the higher the temperature, the faster chemical reactions occur. Therefore, the more life there will be.

• Tropical regions contain 2/3 (66 %) of all of Earth’s land species.

How Does Biodiversity Affect You?

• Variety in our diets help to keep us healthy.• Biodiversity helps to improve food crops.• Biodiversity provides many useful materials

such as building supplies, fibers (cotton, wool), and medicines. In fact, most medicines used today originally came from wild plants. Can you think of any?

Biodiversity = Variety

Medicinal Plants

What reduces biodiversity?

• The number one cause of biodiversity reduction is extinction.

• An extinct species is one that was once living on Earth but has died out.

• Can you name one extinct organism?

Contributing Factors to Biodiversity Loss

• Loss of species.• Loss of habitat.• Divided habitats.• Introduced species. • Pollution of land, air,

and soil.• Global warming.• Ozone depletion.

Human Effects on Biodiversity

• From 1980-2000, close to 40 species of plants and animals disappeared forever.

• It’s projected that 25% of species on Earth today will be extinct by 2050 mainly because of human activity.

Endangered Species• A species in danger of

becoming extinct is classified as endangered.

• This is intended to provide protection from extinction.

• Does it work?

Threatened Species• If a species is

likely to become endangered in the near future, it is classified as threatened.

• This is intended to protect habitat as well as the organism itself.

Threatened and Endangered Species in Alabama

Habitat Loss

• One of the main reasons that organisms become threatened, endangered, or extinct.

• When forests are clear cut, many organisms lose their home/hunting grounds.

• When waters are polluted, aquatic organisms lose their home/hunting grounds.

• When habitats are divided, large predators lose their hunting grounds often leading to attacks on humans.

Habitat Loss• In many parts of the

world it’s common practice to cut down forests without any regard for the animals living there.

• Habitat loss = DEATH

Division of Habitat• When a forest, lake, or

large preserve has a road, damn, or settlement built across a plant or animal’s territory the animals lose part of their habitat.

Introduced Species

• Species from another part of the world that are brought into an ecosystem by human actions.

• They have no competitors or predators in the new area, so their populations grow rapidly.

• They can crowd out or consume native species.

Other Introduced Species…

Pollution

• Land, water, and air pollution affect biodiversity.

• Soil contaminated with oil, chemicals, or other pollutants can harm plants and limit growth.

• Any reduction in plant growth can limit biodiversity because of lost habitat, food sources.

Water Pollution

• Aquatic organisms are extra sensitive to pollutants.

• Pollutants come from factories, ships, or runoff from farms, golf courses, lawns, and parking lots.

Air Pollution

• Pollution from cars and factories can damage and weaken trees thus destroying the habitats of many animals.

Global Warming

• CO2 gas is released when fuels are burned.

• CO2 absorbs heat, raising temperatures.

• Polar ice caps can melt, raising sea level and flooding coastal areas.

Ozone Depletion• Ozone (O3) layer is about

15-30 km above the Earth.• Caused by

choloroflourocarbons (CFCs) from burning fossil fuels; aerosols.

• Ozone layer absorbs UV rays from the sun; UV harms organisms on Earth, especially us, resulting in an increase of skin cancer cases.

Summary• Biodiversity is the number of species present in an

ecosystem.• Biodiversity is greater in warm, moist climates than in

cold, dry climates.• Extinction occurs when the last member of a species

dies.• Habitat loss, pollution, overhunting, and introduced

species can cause a species to become threatened or endangered.

• You are the future stewards of this planet. What are YOU going to do to save it?