Biodiversity Chapter 10 Environmental Science Biodiversity Number and

Biodiversity Chapter 10 Environmental Science

Biodiversity § Number and variety of different species in a given area § The actual number of species on Earth is unknown § Most are insects (Figure 1 – page 241)

Levels of Biodiversity § Biodiversity is studied at three levels § Species diversity § Differences between populations of species § Ecosystem diversity § Variety of habitats, communities, etc. within or between ecosystems § Genetic diversity § Different genes within a population § Gene – piece of DNA that codes for a specific trait

Benefits of Biodiversity § Species are connected to ecosystems. § Ecosystems are healthy when species do their part in the cycles within the biosphere. § Every species depends on another species whether it is obvious or not. § Keystone species § A species that are clearly critical to the functioning of an ecosystem § Example – sea otter and kelp beds

Benefits of Biodiversity § Species and Population Survival § Species survival depends on the level of genetic diversity § Small, isolated populations have less of a chance of survival § When a population shrinks, the genetic diversity decreases § Creates a bottleneck (Figure 4, page 243) § If population increases again, inbreeding will occur

Benefits of Biodiversity § Medical, Industrial and Agricultural Uses § Prescription drugs § One quarter from plants § Antibiotics § From chemicals in fungi § Crops § Originated from areas of high biodiversity § Hybrids § Crops developed by combining genetic material from other populations

Benefits of Biodiversity § Ethics, Aesthetics and Recreation § Some people believe that species should be allowed to exist whether they have value or not § Religious and cultural beliefs § Ecosystems provide personal enjoyment § Pets § Camping § Watching wildlife § Ecotourism § Tourism that supports the conservation and development of unique areas

Assignment § Section 1 Review § Page 244 § # 1 -4

Biodiversity at Risk § Mass extinction § Many species going extinct in a short period of time § Example – dinosaurs § Scientists think we are in one right now § Humans are primary cause of this § 25 % of all species extinct between 1800 & 2100

Prone to Extinction § Endangered species § Species likely to become extinct if not protected immediately § Threatened species § Species with a declining population § Likely to become endangered if not protected

How Do Humans Cause Extinctions? § Habitat Destruction § Building homes § Harvesting resources § Invasive Exotic Species § Species that are not native to an area § Exotic species can threaten native species § Harvesting, Hunting and Poaching § Excessive hunting is causing extinction § Many countries have laws against poaching § Illegal hunting

How Do Humans Cause Extinctions? § Pollution § Pesticides § Cleaning agents § Drugs and other chemicals § Example – bald eagle § Chemical used over time (DDT)

Areas of Critical Biodiversity § Endemic species § Species that are native to and found only within a limited area § Scientists use the number of endemic species of plants to describe overall biodiversity of an area

Areas of Critical Biodiversity § Tropical Rain Forests § Over half the world’s diversity lives here § Coral Reefs § Contain majority of marine biodiversity § Provide food, tourism, coastal protection § Islands § Have limited, but very distinct species

Areas of Critical Biodiversity § Biodiversity Hotspots § Most threatened areas of high species diversity § 25 identified areas (Figure 9, page 250) § These areas have many endemic species but are also threatened by human activities. § Biodiversity in the United States § High numbers of freshwater fish, pine trees § California Floristic Province § 3, 488 native plant species

Assignment § Section 2 Review § Page 251 § # 1 -4, 6

The Future of Biodiversity § Saving Species One at a Time § Captive-Breeding Programs § Breeding species while in captivity § Then the species will be reintroduced to their natural habitats § Example – California condor § § § Lost habitat, poaching, lead poisoning In 1986, 9 condors captured In 2002, 58 condors released and 102 in captivity § Preserving genetic material § Scientists collect germ plasm from plants & animals to save for many years

Saving Species One at a Time § Zoos, Aquariums, Parks and Gardens § Living museums of world’s biodiversity § Some species last hope of survival § Only have enough resources to preserve more than a fraction of world’s rare and threatened species § More study needed § Not all captive species will survive or reproduce in the wild

Preserving Habitats & Ecosystems § Conservation Strategies § Scientists concentrate on saving ecosystems instead of individual species § Can save more species this way § Scientists are concentrating on hotspots § Scientists are also identifying native habitats to preserve and restore § Scientists are promoting products that have been harvested with sustainable practices

Making A Difference § Page 264 -265 § Dr. Wilson § Write essay answering the following questions: § What is an entomologist? § What is a conservationist? § Why is it important to have conservationists like Dr. Wilson in the world today? (At least 3 reasons why)

Legal Protections for Species § US Laws § Endangered Species Act § Created in 1973 1. Protects plant and animal species in danger of extinction by adding them to a list § 983 plant and animal species on endangered or threatened list in 2002 2. Protects species on the list from human harm § Fines given to people who violate the law 3. Federal government can not carry out a project that jeopardizes a listed species

Legal Protections for Species § Recovery & Habitat Conservation Plans § Required by Endangered Species Act by the USFWS (US Fish and Wildlife Service) § Plan must be in place for all listed species § Proposed how to protect or restore habitat § Affects real estate developers § Compromises can be reached § Habitat conservation plan § Plan protects species in large area through trade-offs or cooperative agreements

Legal Protections for Species § International Cooperation § International Union for the Conservation of Nature and Natural Resources (IUCN) § In charge of protecting species and habitats § Projects of the IUCN § CITES – an International Treaty to save animals § Stopped the slaughtering of African elephants for tusks § Biodiversity Treaty § International agreement to preserve biodiversity and make sure there is fair use of genetic resources in all countries § Private Conservation Group Efforts

Balancing Human Needs § Trying to protect species often comes in conflict with humans § Example – An endangered species can be a source of food or income for humans § Scientists feel it is important…. § To make the value of biodiversity understood by more humans § This is an important part of protecting a species

Assignment § Section 3 Review § Page 257 § # 1 -4, 6

Chapter 10 Review § Page 259 -261 § # 3 -15, 17, 20 -23, 26 -27, 31 -32