1. Overusing Resources: -Two Main Types: * Renewable: sunlight, forests, air, soil * Nonrenewable: minerals, gems, & fossil fuels * Right now, we over use both types, but esp. nonrenewable resources 3:09

2. Energy Consumption From Fossil Fuels: * Oil, coal, & natural gas provide 80% of energy used in industrialized countries * NONRENEWABLE & causes pollution 3:15

3. Pollution : = any physical, chemical, or biological change that negatively affects organisms or negatively alters the environment * Includes air, water, & soil pollution * At least 1.1 billion people lack an adequate supply of safe drinking water * More than twice that don’t have modern sanitation 3:19

4. Global climate change : * Human activities release carbon dioxide (CO 2 ) & other greenhouse gases that trap heat in the atmosphere * Over the past 200 years, atmospheric CO 2 has increased by 35% * By 2100… global temps will probably warm 1.5 to 6  C (  F) 3:23

5. Overpopulation * More people = increased use of resources = destruction of environment 3:27

6. Loss of Biodiversity: * Biodiversity: diversity of organisms (different species) in an area * Over the past century, more than 800 species have gone extinct & at least 10,000 species are now threatened Tasmanian tiger- extinct 1936 Great Auk - extinct 1844 tree kangaroo- endangered cheetah- endangered 3:29

* Number species on Earth known & described is ~1.7 million * Estimated to actually be ~ 10 million * INTERESTING FACT: Insects constitute the greatest number of species (nearly 1,000), followed by plants, arachnids, fungi, mollusks, and vertebrates 3:32

* We depend on healthy ecosystems and many organisms for balanced nutrient cycles & energy flow. * Every species is dependent on or depended upon by at least one other species. * We use organisms for food, clothing, shelter, & medicine. * About 25% of drugs prescribed in the US are derived from plants. Almost all antibiotics are derived from chemicals found in fungi. 3:36

* Tropical rain forests, coral reefs, coasts, & islands have high biodiversity * ~50% world’s species live in tropical rain forests * 25 spots on Earth are “Biodiversity hotspots” = have high #s of endemic species & are threatened * Endemic = found in a limited area; risk extinction * The hotspots include places like Madagascar, the Caribbean, and tropical forests in South America, China, the Philippines, etc. 3:36

Lemurs of Madagascar Rock macaque of Taiwan Galapagos Tortoises Philippine Crocodile 2:58

* Endangered species = likely to go extinct in near future * ~10,000 animals worldwide are “endangered” * Threatened species = populations are declining Threats to Biodiversity: 1. Habitat fragmentation & destruction (Ex: Florida panther almost went extinct) 2. Pollution 3. Overharvesting & Poaching (illegal hunting) (Ex: fishing industries) 4. Invasive species (not native to a particular region; Ex: Fire ants, kudzu) 3:24

1.Captive breeding: zoos, conservation groups 2. Endangered Species Act (1973) – law against hurting, trading, or destroying habitat of endangered species 3. IUCN (International Union for the Conservation of Nature and Natural Resources) – founded 1948; works to protect species & habitats worldwide 4.CITES (Convention on International Trade in Endangered species) – treaty pass in 1973 by 170 countries; controls trade of wildlife 5. National Parks & Wildlife Sanctuaries 3:24