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6.3 Biodiversity PowerPoint Notes THINK ABOUT IT From multicolored coral reefs to moss-draped forests, variety is “the spice of life.” Variety in the biosphere gives us more than interesting things to look at. Our wellbeing is closely tied to the well-being of a great number of other organisms, including many that are neither majestic nor beautiful to our eyes. The Value of Biodiversity Why is biodiversity important? Biodiversity’s benefits to society include contributions to _______________ and __________________, and the provision of ecosystem goods and services. Biological diversity, or biodiversity, is the total of all the _______________ ____________________________________. What kinds of biodiversity exist, and what value do they offer society? Types of Biodiversity Biodiversity exists on three levels: _____________________________ _____________________________ _____________________________ __________________________ refers to the variety of habitats, communities, and ecological processes in the biosphere. The _______________________________________, or in a particular area, is called species diversity. To date, biologists have identified and named more than ________________ species, and they estimate that at least ________________ more are yet be discovered. ____________________________ can refer to the ______________ of all different forms of _____________________ carried by a particular species, or by all organisms on Earth. Within each species, genetic diversity refers to the total of all different ______________________ present in that species. Valuing Biodiversity Biodiversity is one of Earth’s greatest natural resources. When biodiversity is lost, significant ____________ to the ____________ and to _______________ may be lost along with it. Biodiversity’s benefits to society include contributions to _____________ and _________________, and the provision of ecosystem ___________ and _________________. Biodiversity and Medicine _________________ are the original source of many medicines. For example, a foxglove plant contains compounds called digitalins that are used to treat ______________________. These plant compounds are assembled according to instructions coded in ___________. The genetic information carried by diverse species is like a “natural library” from which we have a great deal to learn. 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—through plant breeding or genetic engineering—to __________________ or __________________, or other useful ___________, to crop plants. Biodiversity and Ecosystem Services The number and variety of species in an ecosystem can influence that ecosystem’s _________________, ______________, and value to humans. Sometimes the presence or absence of a single keystone species, like the sea otter, can completely change the nature of life in an ecosystem. When the otter population falls, the population of its favorite prey, sea urchins, goes up. Population increases in sea urchins cause a dramatic decrease in the population of sea kelp, the sea urchin’s favorite food. Also, healthy and diverse ecosystems play a vital role in maintaining __________, ____________, and ______ quality Threats to Biodiversity What are the most significant threats to biodiversity? Humans reduce biodiversity by ___________________, ____________, introducing ______________________, releasing pollution into food webs, and contributing to climate change. Human activity today is causing the greatest wave of extinctions since ___________________ disappeared. The current rate of species loss is approaching ________ times the “typical” rate. As species disappear, the potential ________________ to human knowledge that is carried in their genes is ___________. _____________ diversity is related to ___________ diversity. The more genetically diverse a species is, the greater its chances of _____________ __________________. So as human activity reduces genetic diversity, species are put at a greater risk for extinction. Species diversity is also linked to ________________ diversity. As ecosystems are damaged, the organisms that inhabit them become more _____________________________. Altered Habitats When natural habitats are eliminated for ___________________ or for urban development, the number of species in those habitats ___________, and some species may _______________________. Development often splits ecosystems into pieces, a process called __________ ________________, leaving habitat “islands.” A biological island can be any patch of habitat _____________________________. For example, deforestation for housing developments in Florida has led to forest “islands.” The smaller a habitat island, the ___________ the species that can live there and the smaller their ______________. Both changes make _____________ and _____________ more vulnerable to other disturbances. Hunting and the Demand for Wildlife Products Humans can push species to extinction by hunting. Some animals are hunted for _______ or for their valuable _________ or skins. Others, like green parrots, are hunted to be sold as _________. Hunted species are affected even more than other species by habitat fragmentation because fragmentation increases _________________ __________________ and limits available _________________________ for prey. The Convention on International Trade in Endangered Species (CITES) ______ international trade in products from a list of ____________________ _____________________. Introduced Species Organisms introduced to new habitats can become invasive and _______________ _______________. One European weed, leafy spurge, infests millions of hectares across the Northern Great Plains. Leafy spurge displaces grasses and other food plants, and it can sicken or kill cattle and horses. Pollution Many _______________ threaten biodiversity. ___________, for example, prevents birds from laying healthy eggs. Acid rain places stress on land and water _________________. Increased ______________________ in the atmosphere is dissolving in oceans, making them more ______________, which threatens biodiversity in ________________ ecosystems. Climate Change Organisms are adapted to their environments and have specific tolerance ranges to ______________ and other _______________ conditions. If conditions change beyond an organism’s tolerance, the organism must ___________ to a more suitable location or ________________________. Species in fragmented habitats, such as these forest “islands” in Florida, are particularly vulnerable to climate change because if conditions change they may not be able to _____________________ to a suitable habitat. Conserving Biodiversity How do we preserve biodiversity? To conserve biodiversity, we must preserve individual _____________, preserve _____________ and ______________, and make certain that human neighbors of protected areas benefit from participating in conservation efforts. Protecting Individual Species The Association of Zoos and Aquariums (AZA) oversees species survival plans (SSPs) designed to protect threatened and endangered species. In the AZA captive breeding program, mating pairs of animals are carefully selected to ensure maximum genetic diversity. The ultimate goal of an SSP is to ___________________________ to the __________. More than __________________________ are currently covered by SSPs. Preserving Habitats and Ecosystems Global conservation efforts today strive to protect not just individual species but entire _______________________. The goal is to preserve the natural ____________________ of ________________________________ at once. Governments and conservation groups work to set aside land as ________ and ______________________. The United States has national parks, forests, and other protected areas. ___________________________________ are being created to protect coral reefs and marine mammals. To make sure that conservation efforts are concentrated in the most important places, conservation biologists have identified ecological “______ ___________”. An ______________________________________ is a place where significant numbers of species and habitats are in immediate danger of extinction. By identifying these areas, ecologists hope that scientists and governments can better target their efforts to save ______________________________ ____________________. Preserving Habitats and Ecosystems: Ecological Hot spots (shaded) Considering Local Interests Protecting biodiversity often demands that individuals change their ___________ or the way they ______________________________. It is often helpful to offer some reward or incentive to the people or communities involved. The United States government, for example, has offered _______________ to people who’ve installed ______________________ or bought _____________ cars. Many communities in Africa, Central America, and Southeast Asia have set aside land for ___________________________ and _______________ ___________________, like Thailand’s Elephant Nature Park, to attract tourist dollars. In some Australian communities, farmers were paid to ________ _____________ along rivers and streams as part of wildlife corridors ___________________ forest fragments. Considering Local Interests The use of ________________ is one strategy aimed at encouraging industries to cut __________________ use. Companies are allowed to release a certain amount of ______________ into the environment. Any unused carbon may be __________________ at a set market value or traded to other companies. This strategy encourages industries to pay for ______________ __________ machinery and to adopt ____________________________ practices.