Lesson Overview Biodiversity Lesson Overview Biodiversity THINK ABOUT

Lesson Overview Biodiversity

Lesson Overview Biodiversity…. THINK ABOUT IT BIODIVERSITY means life variety From multicolored coral reefs to moss-draped forests, variety is “the spice of life. ”

Lesson Overview Biodiversity The number of different species in the biosphere, or in a particular area, is called species diversity. To date, biologists have identified and named more than 1. 8 million species. They estimate that at least 30 million more are yet be discovered.

Lesson Overview Biodiversity The definition of Biodiversity is the total of all the genetically based variation in all organisms in the biosphere. Why is biodiversity important? 1. Medicine 2. Agriculture 3. Stable ecosystem

Lesson Overview Biodiversity and Medicine Wild species are the original source of many medicines. Example, a foxglove plant contains compounds used to treat heart disease.

Lesson Overview Biodiversity and Agriculture Most crop plants have wild relatives. For example, wild potatoes in South America come in many colorful varieties. These wild plants may carry genes we can use for disease, pest resistance, or other useful traits to crop plants. The transfer of genes can occur through plant breeding or genetic engineering.

Lesson Overview Biodiversity and a Stable Ecosystem The number and variety of species in an ecosystem can influence that ecosystem’s stability, productivity, and value to humans. A healthy and diverse ecosystems play a vital role in maintaining soil, water, and air quality.

Lesson Overview Biodiversity Threats to Biodiversity What are the most significant threats to biodiversity?

Lesson Overview Biodiversity HUMANS Humans reduce biodiversity by altering habitats, hunting, introducing invasive species, releasing pollution into food webs, and contributing to climate change. Human activity today is causing the greatest wave of extinctions since dinosaurs disappeared. The current rate of species loss is approaching 1000 times the “typical” rate. As species disappear, the potential contribution to human knowledge that is carried in their genes is lost. Species diversity is related to genetic diversity. The more genetically diverse a species is, the greater its chances of surviving disturbances. So as human activity reduces genetic diversity, species are put at a greater risk for extinction.

Lesson Overview Biodiversity Altered Habitats When natural habitats are eliminated for agriculture or for urban development, the number of species in those habitats drops, and some species may become extinct.

Lesson Overview Biodiversity Hunting and the Demand for Wildlife Products Humans can push species to extinction by hunting. Some animals are hunted for meat or for their valuable hides or skins. Others, like green parrots, are hunted to be sold as pets. The Convention on International Trade in Endangered Species (CITES) bans international trade in products from a list of endangered species.

Lesson Overview Biodiversity Introduced Species Organisms introduced to new habitats can become invasive and threaten biodiversity. Purple Loosestrife seeds were probably accidentally brought over in the ballast water of ships to the Eastern United States. It was also brought over for ornamental purposes. It spread so extensively because of boats, animals, and also the flooding of certain areas. This plant's ability to survive in many conditions allows it to outcompete other native plants, such as cattails, sedges, and ferns, for nutrients. Without the native plants for wildlife, their source of food and shelter decrease, and they suffer. Purple Loosestrife lacks natural predators which is why it continues to grow.

Lesson Overview Biodiversity Pollution Many pollutants threaten biodiversity. DDT, for example, prevents birds from laying healthy eggs. Acid rain places stress on land water organisms. Increased carbon dioxide in the atmosphere is dissolving in oceans, making them more acidic, which threatens biodiversity in marine ecosystems.

Lesson Overview Biodiversity Climate Change Organisms are adapted to their environments and have specific tolerance ranges to temperature and other abiotic conditions. If conditions change beyond an organism’s tolerance, the organism must move to a more suitable location or face extinction.

Lesson Overview Biodiversity Conserving Biodiversity How do we preserve biodiversity? To conserve biodiversity, we must: • protect individual species • preserve habitats and ecosystems Governments and conservation groups work to set aside land as parks and reserves. The United States has national parks, forests, and other protected areas. Marine sanctuaries are being created to protect coral reefs and marine mammals.

Lesson Overview Biodiversity Sustainable Resource Using natural resources in a way that does not cause long-term environmental harm is called sustainable development. Sustainable development should cause no long-term harm to the soil, water, and climate on which it depends. It should consume as little energy and material as possible. Sustainable development must be flexible enough to survive environmental stresses like droughts, floods, and heat waves or cold snaps.