Biodiversity Chapter 10

Section 1 What is Biodiversity

A World Rich in Biodiversity Biodiversity – the number of different species in a given area Tropical rain forests have highest biodiversity on earth Known species – species that are collected and described scientifically 1.7 million species (most of which are insects) Unknown species – Species not identified as of yet, located in remote locations More than 2 million possible (to be identified) Levels of diversity Species diversity : Number of species in a given area (most commonly know as biodiversity) Ecosystem diversity: All the different habitats and ecological processes in an ecosystem Genetic diversity: All the different genes in all the members of a population A gene is a part of DNA that determines one particular trait (blue eyes, widow peak) A World Rich in Biodiversity

Benefits of Biodiversity Species are connected to ecosystems. Every species is either dependent on or depended upon by at least one other species. Think food webs, niches Keystone species – critical to the entire ecosystem Sea Otters: loss of the otter - led to the loss of kelp beds Benefits of Biodiversity

Benefits of Biodiversity Species and Population Survival Genetic diversity is critical to species survival. Environmental changes affect less diverse populations more Ice Age – species not adapted to cold die - but species with genes to survive cold live on If no one in species had cold gene, all die But what happens to genes in all the species that died? All other genes lost Bottleneck effect – When a population is reduced to a few members. Only certain genes get through the event. Benefits of Biodiversity

Industry finds new chemicals in all types of species Medicines and cures are constantly being found as we locate new species Industry finds new chemicals in all types of species Better resistant crops being made because of genetic crossing Ethics, Aesthetics, and Ecotourism Should we preserve species because they deserve to be here? Should we preserve species because they are nice to look at and make our lives beautiful Ecotourism – a form of tourism that supports the conversation and sustainable development of ecologically unique areas.

Time for a reading quiz That’s all for 10.1

Section 2 Biodiversity at Risk

Mass extinction – extinction of many species in a short period of time Five previous mass extinction events Due to global climate change Dinosaurs: ice ages and meteorites Possible cause of the next (current??)mass extinction: Due to human activities From 1800 to 2100 up to 25% of all species may become extinct Endangered species – species that will go extinct if not protected immediately Usually a small population in a limited habitat Threatened species – species will become endangered if not protected Current Extinctions

How Do Humans Cause Extinctions Habitat Destruction and Fragmentation We use land for homes and food production In the process – we destroy and fragment the habitats of other species. Habitat loss is causing 75% of all current extinctions Florida Panther: one of the most endangered species in North America (due to habitat loss) How Do Humans Cause Extinctions

How Do Humans Cause Extinctions Invasive species New species introduced to an environment Native species have no defenses, and new species have no predators Kudzu, Cane Toads, Fire Ants Harvesting, Hunting, Poaching Passenger pigeon hunted out of existence, bison close People want rare species as a pet, food, medicine Monkey brains, shark fins, Poaching – capturing protected species against the law Ex: elephants for ivory (tusk) ; tigers for healing properties Pollution Chemicals being dumped have harmful effects on other species Ex: DDT in the food chain caused bald eagle egg shells to weaken Bald eagle nearly extinct until DDT banned. How Do Humans Cause Extinctions

Areas of Critical Biodiversity Endemic Species – species that live in a small specific habitat Tropical Rain Forest Home to half of world’s species Most not yet observed, but losing them as we clear the rain forest for farming and housing Coral Reefs – Most of biodiversity in ocean A major source of food and ecotourism In danger due to overfishing, and pollution Hot Spots – the most threatened areas of high diversity on Earth Madagascar, Philippines, Florida Everglades, California Coast, Hawaii United States Biodiversity We have several of the hotspots (Florida Everglades / coastal regions) Are we taking care of them? Areas of Critical Biodiversity

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Section 3 The Future of Biodiversity

Saving Species One at a Time When a species is nearing extinction what can be done to help? Captive breeding Species are bred in captivity (zoos or shelters) and will be released into wild when enough are bred California Condor Preserving Genetic Material Germ plasm – genetic material from reproductive cells Stored (usually frozen) for future use. Same as heirloom tomato seeds! Zoos and Aquariums Not just for entertainment Home for endangered species Successful breeding programs - Pandas! Saving Species One at a Time

Preserving Habitats and Ecosystems Conservation Strategies Focus on whole ecosystem not individual species Restore native habitats and expand them Legal Protections - US Endangered Species Act – passed in 1973 Fish and Wildlife Service must keep list of all endangered or threatened species Endangered and threatened species cannot be caught or killed. Endangered/threatened plants may not be uprooted No part of an endangered/threatened species may be sold or traded US Government cannot do any projects that might impact listed species The U.S. Fish and Wildlife Service must prepare a species recovery plan Preserving Habitats and Ecosystems

Legal Protection – International IUCN – International Union for the Conservation of Nature and Natural Resources Advise governments on endangered species Publishes a “Red Lists” of endangered species around the world CITES – Convention on International Trade in Endangered Species Elephant Ivory Tusks – Poachers after them CITES made a worldwide ban on selling ivory Elephant poaching dropped Biodiversity Treaty Agreement generated during the Earth Summit (1992 – Rio de Janeiro) Goal is to preserve biodiversity and ensure sustainable/fair use of genetic resources in ALL countries

Time for a reading quiz That’s all for 10.3