+ Biodiversity Miss Napolitano & Mrs. Rodriguez Environmental Science

+ Biodiversity Biodiversity: the number of different species in a given area Short for “biological diversity” There are ~1.7 million species on Earth Most are insects – yuck! Not all species are known (collected/described scientifically)

+ Keystone vs. Flagship Species Keystone species: species that are critical to the functioning of an ecosystem Ex: sea otter – loss leads to loss of kelp beds Flagship species: well-known, popular species Usually used to attract support for conservation Keystone species are not necessarily the best- known species in the environment!

+ Benefits of Biodiversity Genetic diversity increases the chance that some members will survive environmental changes Variety of organisms used for food, clothing, shelter, & medicine ¼ of prescription drugs derived from plants *Wild Pharmacy!

+ Endangered vs. Threatened Species There have been 5 mass extinctions in Earth’s history Takes millions of years for biodiversity to come back after a mass extinction Large populations that easily adapt are less likely to become extinct Ex: cockroaches, rats Threatened species: species with a declining population Endangered species: species that is likely to become extinct if protective measures not taken

+ Humans & Extinction Humans accelerate rate of extinction due to habitat destruction, pollution, & overharvesting of species Introduce exotic species – species that are not native to a particular area Continue poaching – illegal hunting, fishing, harvesting, or trading of wildlife

+ Areas of Critical Biodiversity Different parts of the world have different amounts of species diversity Lots of endemic species: native species found within a limited area ~1/2 of Earth’s species live in tropical rain forests Only make up ~7% of Earth’s land surface Most species have never been described Coral reefs very diverse but ~60% are threatened by human activities Ex: overfishing, pollution Organisms on islands become isolated, adapt to surroundings, & evolve into new species

+ Biodiversity Hotspots Biodiversity hotspots: the most threatened areas of high species diversity Have high numbers of endemic species but threatened by human activities Most have lost at least 70% of original vegetation 3 hotspots in the US: California floristic province, Caribbean, & Polynesia/Micronesia Lots of biodiversity in the US because many different types of environments & ecosystems

+ The Future of Biodiversity – Conservation Efforts Captive-Breeding Programs Breeding species in captivity & reintroducing into natural habitats Preserving genetic material in germ-plasm banks Zoos, aquariums, parks, & gardens Problems with captive species: Organisms have more difficulty surviving or reproducing in wild Vulnerable to infectious disease Small populations at risk of genetic disorders from inbreeding Focus is now on conserving ecosystems instead of individual species, especially hotspots.

+ Legal Protection for Species – Endangered Species Act (1973) US Fish & Wildlife Service (USFWS) compiles list of all endangered & threatened species – 1, 272 species in 2005 Anyone who harms, buys, or sells any part of listed species is subject to fines Federal government cannot carry out projects that jeopardizes listed species Recovery plan developed for each listed species Protect/restore habitats Controversial – does not always benefit humans Habitat conservation plan: protects species through trade-offs or cooperation agreements

+ International Cooperation International Union for the Conservation of Nature and Natural Resources (IUCN): conservation on international level Red Lists of species in danger of extinction developed Advises governments on how to manage natural resources United Nations Conference on Environment and Development (1992) AKA Earth Summit 100 world leaders with 30,000 other participants Biodiversity Treaty: preserves biodiversity & ensures sustainable & fair use of genetic resources in all countries

+ Ecotourism Ecotourism: tourism that supports the conservation and sustainable development of ecologically unique areas