Chapter 10: Biodiversity

Chapter 10 Biodiversity Big Ideas

The huge diversity of life on Earth is critical to all species.

Some factors about species make them prone to extinction.

Human activities are causing large numbers of species to go extinct.

Section 1: What is biodiversity?

How many species live on Earth? Describe the types of biodiversity. Explain the importance of biodiversity. Terms: biodiversity, gene, keystone

species, ecotourism

Biodiversity Biodiversity: the

number of different species in a given area

Tropical rain forests

What factors lead to biodiversity?

• About 1.7 million species are known

• Estimated to be greater than 10 million

•Why so many unknown?

Biodiversity

Which species rule the world?

Levels of BiodiversitySpecies Biodiversity: differences between

populations number of different

species in an area

Ecosystem Diversity: how many types of

habitats or communities in an area

Genetic Diversity: number of genes in all members of a population

What is a gene?

Gene: a piece of DNA code for a specific trait inherited

Tall, short, brown eyes, etc.

Genetic Diversity among corn

Levels of Biodiversity

Genetic diversity: Differences in DNA among individuals

Species diversity: Variety of species in a given area

Ecosystem diversity: Variety of habitats, ecosystems, communities

Ecosystem diversity often leads to species diversity and often leads to genetic diversity

Did You Know?In general, biodiversity increases toward the equator.

Who cares about Biodiversity?A Variety of Answers

We Care !

Benefits of Biodiversity Genetic Diversity

Key To Survival Small isolated

populations unlikely to survive• Genetic mutations

from inbreeding can occur

More diversity = more likely to survive

Why is genetic diversity important?

Cavendish banana

“ The fungus Fusarium oxysporum wiped out the previous species of bananas (the Gros Michel) in the 1950s. Now it’s back, having evolved to be able to take on the previously resistant “back-up” species of banana — the Cavendish — that replaced the superior Gros Michel banana after it was wiped out. “

Benefits of Biodiversity: Ecosystem Services

Intact environments provide ecosystem services• water purification and pest control

High biodiversity increases stability of communities and ecosystems• enables them to perform services.

Stable ecosystems are resistant and resilient

Benefits of Biodiversity

Keystone Species: species that is critical to ecosystem survival• Sea Otter• Grey Wolf• Beaver

Keystone Species

Food Web Depends Upon Krill

Benefits of Biodiversity Species

Population and Survival:• Genetic diversity

increases chance that some survive environmental pressures or changes

Benefits of Biodiversity

Medical, Industrial, Agricultural Uses

Food, cloths, shelter, chemicals and medicine often comes from variety of organismsSee Table 1 page 243

Medical

Medicine: Organisms contain compounds that are useful for treating disease Did You Know?

Of the 150 most prescribed drugs in the United States, 118 originated in nature.

The yew tree, an original source of Taxol, a cancer-fighting drug

Agricultural

Humans benefit every time we eat

Most foods come from areas of high biodiversity

Benefits of Biodiversity

Ethics, Aesthetics and Recreation

Moral, religious purposes for all species

Personal enjoyment

Dolphin Tour Off NJ Beaches

Benefits of Biodiversity

Ecotourism: tourisms that supports conservation

Wildlife, birding, wilderness hiking

People make money by having people view wildlife

Section 1 Review

How many species live on Earth? Describe the types of biodiversity. Explain why biodiversity is important.

Section 2: Biodiversity at Risk

What does it mean when a species is threatened or endangered?

What makes some species more prone to extinction?

What are the largest threats to biodiversity? Which areas are likely to have high

biodiversity?

Biodiversity has increased over time, but mass extinctions are also natural events (5 major events)

How do we get this data?

Extinctions Species gone forever NORMAL Mass Extinction: short

period of time when large number of species go extinct (65 MYA)

Currently in a mass extinction…caused by humans

Rapid climate change

• There have been five mass extinctions in Earth’s history.

• Each time, more than 1/5 of all families and 1/2 of all species have gone extinct.

Biodiversity at RiskCurrent extinction rate 100 to 1000 times greater than the natural background rate

In 2009, 1321 species in the U.S. were classified as endangered or threatened.

Endangered: At serious risk of extinction

Threatened: Likely to become endangered soon through all or part of its range

ExtinctionsCertain traits make

some species more vulnerable:

Small populations Specialized

• Niche• Habitat

Need large range Migrate Valuable to humans

Species squeezed into smaller and smaller fragmented habitat

Current Extinctions

Endangered Species: is likely to go extinct if actions not taken

Threatened: population declining and likely to become endangered

Current Extinctions

TNC estimates 1/3rd of 21,000 identified U.S. animal and plant species are vulnerable.

30,000 of the world’s species and 1,200 in U.S. are officially endangered.

Types of endangered species worldwide

How do humans cause extinctions?

“HIPPO”Habitat

destruction Invasive

speciesPopulation

(humans) growth

PollutionOverharvesting

Habitat Loss/Fragmentation

Habitat Fragmentation

Habitat fragmentation: Patches of suitable habitat surrounded by unsuitable habitat

In general, larger habitat fragments can support greater biodiversity than smaller fragments

Humans Causing Extinctions

Habitat Destruction causes 75-80%

Large creatures need a lot of land

Invasive Species: exotic species not native to area can destroy an ecosystem

Invasive Species

Invasive species can out-compete and displace native species

Invasive Species

CA Agricultural Checkpoints

Humans Causing Extinction Over-harvesting

excessive hunting• (bison in U.S., fish,

passenger pigeon) Poaching: illegal

hunting• Common in poor

countries for food, medicines, income

Pollution air, water, land• DDT, drugs, chemicals

Causes of Extinction Climate Change

Increasingly becoming a factor in biodiversity loss

Unlike the other factors, climate change has a potential global effect on biodiversity

Areas of Critical Biodiversity

Tropical Rain Forests

Coral Reefs Coastal

Ecosystems IslandsWhy these

areas????

Just 2.3% of the planet’s land surface is home to 50% of the world’s plant species and 42% of its vertebrate animal species.

Areas of Critical Biodiversity

Hotspots: most threatened areas of high biodiversity

Roughly 25 worldwide

Madagascar Parts of California Caribbean

Hotspots

Large numbers of endemic species: species native to that area

US Hotspots

California Floristic Province – • 3488 native plants / 2124 endemic / 565 threatened or endangered• agriculture, housing, dams, overuse of water, destructive recreation,

mining

Section 2 Review

What does it mean when a species is threatened or endangered?

What makes some species more prone to extinction?

What are the largest threats to biodiversity? What areas are likely to have high

biodiversity?

Section 3: Future of Biodiversity

List and describe efforts to save individual species

Explain the advantages of protecting entire ecosystems rather than individual species

Describe the main parts of the Endangered Species Act

Saving Individual SpeciesCaptive Breeding

Programs: breeding species in captivity with hopes of reintroducing into native habitats

Germ Plasm: saving genetic material for possible future use(seeds ,sperm, eggs, DNA)

Zoos &Aquariums, Wildlife Parks & Gardens

Saving Individual Species

Does little to preserve species

Captive individuals may not survive in wild

Small populations have difficult time with inbreeding, diseases

Last resorts

Preserving Habitat and Ecosystems Most effective way

to save a species is protect its habitat

Some species require large areas

What about when they leave protected areas? (Wolves in Yellowstone

Best way to protect individual species is to protect all species in the ecosystem

Legal Protections

Many countries have laws to protect wildlife

Some weak Some strong U.S. law

Endangered Species Act (ESA) one of the strongest

ESAEndangered Species

Act Passed 1973 Protect plant and

animals in danger of extinction

List created of those threatened and endangered

Currently ~1400 listed

2000 total worldwide

ESA• Forbids governments and citizens from harming listed species and habitats

• Forbids trade in products made from listed species

ESA Protects listed

species from harm No development

that harms listed species

What does that all mean?

Can a Shopping Mall be built where listed species lives?

Spotted Owl

ESA Species recovery plan

must be made Habitat Conservation

Plans: plans to protect or restore species habitat

Why do you think ESA may be controversial?

Who would not like this law?

ESAESA: 1973-2010: 92 to

~1400 species listed 54 Species removed

(26 recovery, 10 extinctions, 18 errors, rest discovered more)

60% plants, 40% animals

TNC says 1/3rd of all U.S. species…30,000 not 1,260

NJ ESA Listhttp://www.state.nj.us/dep/fgw/tandespp.htm

Wildlife Corridors Connect habitat

fragments enabling once-isolated populations to interbreed

Interbreeding increases genetic diversity

Yellowstone to Yukon

Internationally International Union for the

Conservation of Nature & Natural Resources (IUCN)• Red List of worldwide

endangered species• CITES Treaty 1989

(Convention on International Trade of Endangered Species)

• Illegal to trade endangered species

Ivory Tusks

Internationally Much more difficult

among may poorer countries

International treaties hard to ratify, verify• The Biodiversity Treaty

Oceans of particular concern

Private conservation efforts often more effective (WWF,TNC,CI)

• http://animal.discovery.com/tv/whale-wars/

Section 3 Review

List and describe efforts to save individual species.

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

Describe the main parts of the Endangered Species Act.

Terms: Endangered Species Act, habitat conservation plans, CITES

Chapter 10 Biodiversity Review

There is a huge diversity of life on Earth that is critical to all species. .

There are some factors about species that make them prone to extinction.

Human activities are causing large numbers of species to go extinct.