Chapter 10: Biodiversityp. 240-258

1. What is biodiversity?2. Biodiversity at Risk

3. The future of Biodiversity

Key Terms

• Biodiversity• Gene• Keystone species• Ecotourism• Endangered species• Threatened species

• Exotic species• Poaching• Endemic species• Germ plasm• Endangered species act• Habitat conservation

plan• Biodiversity treaty

objectives• Describe the diversity of species types on Earth,

relating the difference between know numbers and estimated numbers.

• List and describe 3 levels of biodiversity.• Explain 4 ways in which biodiversity is important

(benefits) to ecosystems and humans.• What are some medical examples? • Analyze the potential value of a single species.

(Keystone) Give an example.

What is biodiversity?- Biological Diversity(number and variety of species in an

area)

• What causes species to become extinct?• How many species are becoming extinct?• How much extinction is natural?• Do you think humans should try to prevent the

loss of species? If we study other organisms and preserve

biodiversity helps us for our own survival.

Unknown Diversity-• Haven’t discovered yet• Deep in ocean, remote wilderness• Know more about trees and animals• Less about insects and fungi

Levels of Diversity1. Species diversity- all the differences between

populations of species, as well as between different species

2. Ecosystem diversity- variety of habitats, communities and ecological processes within and between ecosystems

3. Genetic diversity- different genes contained within all members of a population

Benefits of Biodiversity1. Impact the stability of ecosystems and

populations2. Healthy ecosystems to ensure healthy

biosphere3. Increase in genetic diversity (no bottlenecking)4. Medical and Agricultural5. Ethics, Aesthetics and Recreation (ecotourism)

Keystone Species

Sometimes changes in the population of a single species, often called a keystone species, can cause dramatic changes in the structure of a community. – In the cold waters off the Pacific coast of North America, for example, sea otters devour

large quantities of sea urchins.

– Urchins are herbivores whose favorite food is kelp, giant algae that grow in undersea “forests.”

– A century ago, sea otters were nearly eliminated by hunting. Unexpectedly, the kelp forest nearly vanished.

– Without otters as predators, the sea urchin population skyrocketed, and armies of urchins devoured kelp down to bare rock.

– Without kelp to provide habitat, many other animals, including seabirds, disappeared.

– Otters were a keystone species in this community.

Ecology 2010

Biodiversity at risk- objectives • Define and give examples of endangered and threatened species. • Describe several ways that species are being threatened with

extinction globally. What are the humans doing?• What are exotic species? Give an example.• Explain poaching? How does this affect the biodiversity?• Explain which types of threats are having the largest impact on

biodiversity.• List areas of the world that have high levels of biodiversity and many

threats to species.• What are endemic species? Give an example.• Compare the amount of biodiversity in the US to that of the rest of

the world.

Current Extinctions• Past: Most extinctions are mass due to climate

change (natural)• Current: Between 1800 and 2100 25% of all

species on earth may become extinct due to humans (not natural)

Species prone to extinction- small populations in limited areas, small gene pool, migrate, need large or special habitats, exploited by humans

Species prone to extinction-

• Endangered species- likely to happen if protective measures are not taken immediately

• Threatened species- has declining population and that is likely to become endangered if it is not protected

Human Impact?Population growth accelerated and so has rate

of extinctions (table 3 p. 246)1. Destruction of habitats and fragmentation2. the introduction of nonnative species

(Invasive Exotic species)3. Harvesting, hunting, and poaching4. Pollution

Human Impact?1. Destruction of habitats and

fragmentation - Almost 75% of extinctions now occurring- 2001 Florida Panther 80 left

Human Impact?2. the introduction of nonnative

species -Invasive Exotic species – species that is not

native to a particular regionCan threaten native species have no natural

defenses against themHawaii strict rules of brining in plants and fruits-(fire ants, zebra muscles, many plants)

Human Impact?3. Harvesting, hunting, and poaching- 1800s- to 1900s 2 billion passenger pigeons

were hunted to extinction and bison was hunted nearly to extinction

- Pets, house plants, wood ,food, medicine- New laws to regulate hunting, fishing,

harvesting, trade- Poaching- illegal trade of regulated wildlife

Human Impact?4. Pollution-Pesticides, cleaning agents, drugs are making

their way into food webs- DDT and bald eagle only illegal to use in us

Areas of Critical Biodiversity

Endemic species- are native to and found only within a limited area

1. Tropical rain Forest2. Coral Reefs and Coastal Ecosystems3. Island-

Tropical Rain Forest• Covers less than 7% of earths land surface• However over half of world’s species live in

these forest• Many have never been identified or described• Unknown numbers of species are

disappearing as tropical forests are cleared for farming

• http://library.thinkquest.org/11353/trforest.htm

Coral Reefs and Coastal Ecosystems

• Also occupy a small fraction of marine environments yet contain the majority of the biodiversity

• Food, tourism revenue, coastal protection, new chemicals

• 1998 study estimated $375 billion per year• 60% reefs threatened by human activities• (nemo)

Island• Colonized by a limited number of species from

mainland (Galapagos and Hawaiian Islands)• Holds very distinct but limited set of species• Hawaii hold 28 species of birds called

honeycreepers

Biodiversity Hotspots• Most threatened areas of high species

diversity• 25 areas- many have lost at least 70% of

original natural vegetation• Madagascar- 18% forest remains, more than

10,000 flowering plant species are endemic91% of 300 reptile33 species of lemur

Biodiversity in US1. Florida Everglades2. California coastal region3. HawaiiUS holds high numbers of species of freshwater

fish, mussels, snails, crayfish, pine trees and sunflowers

California Floristic Province- 3,488 native plants (2,124 are endemic and 565 threatened or endangered) threatened by local human growth

10.3 objectives

• List and describe 4 types of efforts to save individual species.

• Explain the advantages of protecting entire ecosystems rather than individual species.

• Discuss ways in which efforts to protect endangered species can lead to controversy.

• Describe 3 examples of worldwide cooperative effort to prevent extinctions.

• Explain the outcomes of CITES and Biodiversity Treaty.

Future of BiodiversitySlowing the loss of species is possible, but to do

so we must develop new approaches to conservation and sensitivity to human needs around the globe.

Saving on Species One at a Time

1. Captive- Breading Programs2. Preserving genetic material3. Zoos, aquariums, parks and gardens4. More study needed

1. http://www.thehindu.com/sci-tech/energy-and-environment/article3568516.ece

Captive-Breeding Programs

• Breeding species in captive in hopes to restore populations

• California Condor- Scavengers, habitat loss, poaching, led poisoning

• 1986- 9 remaining left as of 2002 58 condors returned to wild and 102 still live in captivity

• But will they reproduce in the wild to restore their populations

Preserving Genetic Material• Germ Plasm- any form of genetic material that

can reproduce to produce new lifeSeeds, sperm, eggs or DNA• Germ-Plasm banks- store for future use of

research

Zoos, Aquariums, Parks and Gardens

• Original was to put exotic animals on display• Now house few remaining organisms• Botanical gardens house about 90,000 species

of plants worldwide

More study needed• Saving a few individuals does little to preserve

a species• Captive species may not reproduce or survive

again in the wild (Lonesome George)• Vulnerable to infectious disease and genetic

disorders caused by inbreeding• Last resort to save species

Preserving Habitats and Ecosystems

• Number one way to save species is to protect their habitats

• More than just a small plot of land1. Conservation Strategies- protect the

ecosystems rather than the individual speciesMain focus is on world hot spotsMore study is needed for preservation

Legal Protection• US Laws- – 1973 US Congress passed Endangered Species Act

(p255 table 4) protect plant ad animal species in danger of extinction

– USFWS must compile a list– May not be caught or killed, not uprooted, sold or

traded– No project can jeopardizes endangered species– Must prepare a species recovery plan for each

Recovery and Habitat Conservation Plan

• Can be controversial for human use• Habitat conservation plan- attempts to protect

one or more species across large area of land through trade-offs or cooperative agreements

International Cooperation• International Union for the Conservation of

Nature and Natural Resources (ICCN)- try to protect species and habitats

• 200 governmental agencies and over 700 private conservation organizations

• Red List of species in danger ww• Advised governments on ways to manage natural

resources and work with groups life World Wildlife Fund to sponsor conservation projects

International Trade and Poaching• CITES- Convention on International Trade in

Endangered Species• Fist effective effort to stop the slaughter of

African elephants (poaching for Ivory)• Biodiversity Treaty- Earth Summit- 100 world

leaders 30,000 other participants met in 1992 in Rio de Janeiro, Brazil- Treaty goal was to preserve biodiversity and ensure that sustainable and fair use of genetic resources in all countries

Private efforts- • World Wildlife Fund • Nature Conservancy• Greenpeace

Balancing Human NeedsAttempts to protect species often come into conflict

with the interest of the world’s human inhabitants. Sometimes, an endangered species represents a source of food or income, in other cases, a given species may not seem valuable to those who do not understand the species role in an ecosystem

Many conservationists feel that an important part of protecting species making the value of biodiversity understood by more people.