Chapter 21

Question 1

Biodiversity

Answer 1

Sum total of all organism in an area
Split into three specific levels:
-Species diversity
-Genetic diversity
-Ecosystem diversity

Question 2

Species diversity

Answer 2

The number or variety of species in the world or in a particular region

Question 3

Species richness

Answer 3

The number of species

Question 4

Evenness or relative abundance

Answer 4

Extent to which numbers of individuals of different species are equal or skewed

Question 5

Taxonomist

Answer 5

Scientist who classifies species

Question 6

Genera

Answer 6

Related species are grouped together

Question 7

Families

Answer 7

Groups of genera

Question 8

Every species has a 2-part name:

Answer 8

Genus and species

Question 9

Subspecies

Answer 9

Populations of species that occur in different areas and differ slightly from each other

Question 10

Inbreeding depression

Answer 10

Genetically similar parents mate and produce defective offspring

Question 11

Ecosystem diversity

Answer 11

The number and variety of ecosystems

Question 12

Uneven distribution

Answer 12

Latitudinal gradient: species richness increases toward the equator

• Equatorial regions have higher plant productivity, stable climates, and no glaciation.
• Diverse habitats increase niches, which increase species diversity.
• Ecotones (areas where habitats intermix) often have higher diversity.

Question 13

Biodiversity Benefits: Maintain Ecosystem Function

Answer 13

• Biodiversity increases the stability and resilience of communities and ecosystems.
  
  • Decreased biodiversity reduces a natural system’s ability to function and provide services to our society.
• The loss of a species affects ecosystems differently.
  
  • Extinction of a keystone species may cause other species to decline or disappear.

Question 14

Biodiversity Benefits: Free Ecosystem Services

Answer 14

• Provides food, shelter, fuel
• Purifies air and water and detoxifies wastes
• Stabilizes climate, moderates floods, droughts, wind, temperature
• Generates and renews soil fertility and cycles nutrients
• Pollinates plants and controls pests and disease
• Maintains genetic resources
• Provides cultural and aesthetic benefits
• Allows us to adapt to change

Question 15

Organisms Provide Drugs and Medicines

Answer 15

Each year pharmaceutical products owing their origin to wild species generate up to $150 billion in sales

Question 16

Biodiversity Benefits: Economic Benefits

Answer 16

• Biodiversity provides a source of income through tourism.
  
  • Ecotourism: people visit natural areas, creating economic opportunity for residents living near those areas
  • Costa Rica: rainforests
  • Australia: Great Barrier Reef
  • Belize: reefs, caves, and rainforests
• Biophilia: connections that humans subconsciously seek with life

Question 17

Do We Have Ethical Obligations To Other Species?

Answer 17

• Many feel that living organisms have an innate right to exist.
  
  • Biodiversity conservation is justified on ethical grounds.
• Despite our ethical convictions, and biodiversity’s many benefits, the future of biodiversity remains far from secure.

Question 18

Threats to Biodiversity

Answer 18

• Habitat Loss
• Overharvesting
• Invasive species
• Climate change

Question 19

Climate Change and Biodiversity Loss

Answer 19

• Change in earth’s climate system is having global impacts on biodiversity.
• Emissions of greenhouse gases warm temperatures.
  
  • Modifies global weather patterns and increases the frequency of extreme weather events
  • Increases stress on populations and forces organisms to shift their geographic ranges
• Most animals and plants will not be able to cope.

Question 20

Mass Extinction

Answer 20

• Extinction is the rapid extinction of a large number of lineages scattered throughout the tree of life
• Caused by catastrophic events

Question 21

Background Extinction

Answer 21

The lower, average rate of extinction, representing the relatively constant, normal loss of some species.

Question 22

How Do Background and Mass Extinctions Differ?

Answer 22

• Background extinctions typically occur when normal environmental change, emerging diseases, or competition reduces certain populations to zero.
• Mass extinctions result from extraordinary, sudden, and temporary changes in the environment; they cause extinction randomly with respect to individuals’ fitness under normal conditions.
• In a general sense, background extinctions are thought to result primarily from natural selection. Mass extinctions, in contrast, function like genetic drift.

Question 23

The Red List

Answer 23

An updated list of species facing high risks of extinctions

Question 24

Conservation biology

Answer 24

Studies the factors that influence the loss, protection, and restoration of biodiversity

Question 25

Conservation geneticists

Answer 25

Study genetic attributes of organisms to infer the status of their population

Question 26

Minimum viable population

Answer 26

How small a population can become before it runs into problems

Question 27

Equilibrium theory of island biogeography

Answer 27

- Explains how species come to be distributed among oceanic islands - Explains how the number of species on an island results from an equilibrium between immigration and extirpation - Predicts an island’s species richness based on the island’s size and distance from the mainland

Question 28

Area Effect

Answer 28

Large islands contain more species than small islands

Question 29

Endangered Species Act (1973) (ESA)

Answer 29

Forbids the government and private citizens from taking actions that destroy endangered species or their habitats

Question 30

Species at Risk Act (2002)

Answer 30

Canada’s endangered species law - Stresses cooperation between landowners and provincial governments - Criticized as being too weak

Question 31

Umbrella species

Answer 31

Less-charismatic species that would not have generated public interest.

Question 32

UN Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) (1973)

Answer 32

-Protects endangered species by banning international transport of their body parts

Question 33

Convention on Biological Diversity (1992)

Answer 33

- Ensure the fair distribution of biodiversity’s benefits - By 2008, 188 nations had signed on. - Iraq, Somalia, the Vatican, and the U.S. did not join.

Question 34

Biodiversity hotspots

Answer 34

An area that supports a high number of species

Question 35

Endemic species

Answer 35

Species found nowhere else in the world

Question 36

Habitat Restoration

Answer 36

- Restoration can improve degraded habitat | - Reintroduction of wolves to Yellowstone National Park led to dramatic changes in the ecosystem

Question 37

Captive breeding

Answer 37

Individuals are bred and raised with the intent of reintroducing them into the wild

Question 38

Cloning

Answer 38

A technique to create more individuals and save species from extinction

Question 39

Primary causes of biodiversity loss are

Answer 39

Habitat alteration, - invasive species, - pollution, - overharvesting of biotic resources, - climate change

Question 40

Conclusion

Answer 40

- Loss of biodiversity threatens to result in a mass extinction event equivalent to mass extinctions of the past - Human society cannot function without biodiversity’s benefits. - Science can help save species, preserve habitats, restore populations, and keep natural ecosystems intact.