1. Biodiversity and Conservation Biology
Chapter 11
Biodiversity and Conservation Biology

2. This lecture will help you understand:
The scope of Earth’s biodiversity
Ways to measure biodiversity
Background rates and mass extinction
Primary causes of biodiversity loss
The benefits of biodiversity
Conservation biology
Island biogeography theory
Biodiversity conservation efforts
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3. Housekeeping Items
Any highlights from the video and/or the discussion on hunting? Thanks to Jasmine, Anthem, and Norranda in Section 1 for their assistance.
SOLUTIONS meeting Monday at 4 (250, Rm. 308)‏
Did anyone go see “No Impact Man”?
I put some material in the folder about sources for local food, including some heirloom or heritage varieties.
We will do the quiz next week, but will do a review beforehand.
to start off today's lecture topic, a short video about a lion: C2IzE

4. Saving the Siberian tiger
“Except in pockets of ignorance and malice, there is no longer an ideological war between conservationists and developers. Both share the perception that health and prosperity decline in a deteriorating environment. They also understand that useful products cannot be harvested from extinct species.”
– Edward O. Wilson, Harvard University Biodiversity Expert
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5. Saving the Siberian tiger
The largest cat in the world remains only in the Russian Far East mountains
Almost extinct from hunting, poaching and habitat destruction
International conservation groups saved the species from extinction
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6. Biodiversity encompasses several levels
Biodiversity = sum total of all organisms in an area
Species diversity
Genetic diversity
Ecosystem diversity
FIGURE 9.1
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7. Species diversity
Species Diversity = the number or variety of species in the world or in a particular region
Richness = the number of species
Evenness or relative abundance = extent to which numbers of individuals of different species are equal or skewed
Speciation generates new species and adds to species richness
Extinction reduces species richness
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8. The taxonomy of species
Taxonomists = scientists who classify species using physical appearance and genetics
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Every species has a two-part scientific name: genus and species
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9. Genetic diversity
All species consist of individuals that vary genetically from one another to some degree
Encompasses the varieties in DNA among individuals within species and populations
The raw material for adaptation to local conditions
Populations with low genetic diversity are vulnerable
Inbreeding depression = genetically similar parents mate and produce inferior offspring
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10. Ecosystem diversity
Ecosystem diversity = the number and variety of ecosystems
Also encompasses differing communities and habitats
Rapid vegetation change and varying landscapes within an ecosystem promote higher levels of biodiversity
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11. Some groups contain more species than others
Insects predominate over all other life-forms
40% of all insects are beetles
Groups accumulate species by
Adaptive radiation
Allopatric speciation
Low rates of extinction
FIGURE 9.4
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12. Insects outnumber all other species
FIGURE 9.5
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13. Biodiversity is unevenly distributed
Latitudinal gradient = species richness increases towards the equator
Plant productivity and climate stability play key roles
FIGURE 9.6
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14. Latitudinal gradient has many causes
FIGURE 9.7
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15. Biodiversity loss and species extinction
Canadian Species at Risk Act uses categorizes:
Extinction = occurs when the last member of a species dies and the species ceases to exist
Extirpation = the disappearance of a particular population from a given area, but not the entire species globally
Endangered = species in imminent danger of becoming extirpated or extinct
Threatened = species likely to become endangered in the near future
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16. Extinction is a natural process
Paleontologists estimate 99% of all species that ever lived are now extinct
Background rate of extinction = natural extinctions for a variety of reasons
1 extinction per 1 to 10 million species for mammals and marine species
1 species out of 1,000 mammal and marine species would go extinct every 1,000 to 10,000 years
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17. Earth has experienced five previous mass extinction episodes
In the past 440 million years, mass extinctions have eliminated at least 50% of all species
Today’s mass extinction is caused by humans and humans will suffer as a result of it
FIGURE 9.8
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18. Humans set the sixth mass extinction in motion years ago
FIGURE 9.9
Extinctions followed human arrival on islands and continents
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19. Current extinction rates are much higher than normal
The Red List = an updated list of species facing high risks of extinctions
23% of mammal species
12% of bird species
31 to 86% of all other species
Since 1970, 58 fish species, 9 bird species, and 1 mammal species has gone extinct
Actual numbers are undoubtedly higher
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20. Biodiversity loss is more than extinction
The Living Planet Index quantifies degradation
Between 1970 and 2003, the Index fell by 40%
FIGURE 9.10
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21. There are several major causes of biodiversity loss
Reasons for biodiversity losses are multifaceted and factors may interact synergistically
Causes of population decline:
Habitat alteration
Invasive species
Pollution
Overharvesting
Climate change
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22. Habitat alteration causes biodiversity loss
The greatest cause of biodiversity loss
Farming simplifies communities
Grazing modifies the grassland structure and species composition
Clearing forests removes resources organisms need
Hydroelectric dams turn rivers into reservoirs upstream
Urbanization and suburban sprawl reduce natural communities
A few species (i.e., pigeons, rats) benefit from changing habitats
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23. Invasive species cause biodiversity loss
Introduction of non-native species to new environments
Accidental: zebra mussels
Deliberate: food crops
Island species are especially vulnerable
Invaders have no natural predators, competitors, or parasites
Cost billions of dollars in economic damage
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24. Pollution causes biodiversity loss
Harms organisms in many ways
Air pollution degrades forest ecosystems
Water pollution adversely affects fish and amphibians
Agricultural runoff harms terrestrial and aquatic species
The effects of oil and chemical spills on wildlife are dramatic and well known
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25. Overharvesting causes biodiversity loss
Vulnerable species are large, few in number, long-lived, and have few young (K-selected species)‏
The Siberian tiger (The 1989 political freedom in Soviet Union brought the freedom to hunt)
Atlantic gray whale
Sharks
Gorillas
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26. Climate change causes biodiversity loss
Global impact on habitat and biodiversity
Greenhouse gases 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, as evolution has been about adaptation genetically over much more slowly-evolving time periods.
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27. Warming has been the greatest in the Arctic
FIGURE 9.13
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28. Biodiversity provides ecosystem services free of charge
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
The annual value of just 17 ecosystem services = $16 to 54 trillion per year
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29. Biodiversity helps maintain ecosystem function
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
If the species can be functionally replaced by others, it may make little difference
Extinction of a keystone species may cause other species to decline or disappear
Precautionary principle: “To keep every cog and wheel is the first precaution of intelligent tinkering” (Aldo Leopold)‏
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30. Biodiversity enhances food security
Genetic diversity within crops is enormously valuable
Turkey’s wheat crops received $50 billion worth of disease resistance from wild wheat
Wild strains provide disease resistance and have the ability to grow back year after year without being replanted
New potential food crops are waiting to be used
Serendipity berry produces a sweetener 3,000 times sweeter than sugar
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31. Organisms provide drugs and medicines
Each year pharmaceutical products owing their origin to wild species generate up to $150 billion in sales
FIGURE 9.15
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32. Biodiversity provides economic benefits through tourism and recreation
Ecotourism is particularly beneficial in developing countries
Costa Rica: rainforests
Australia: Great Barrier Reef
Belize: reefs, caves, and rainforests
Incentive to preserve natural areas and reduce impacts on the landscape and on native species
Too many visitors can degrade the outdoor experience and disturb wildlife
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33. People value and seek out connections with nature
Biophilia = connections that humans subconsciously seek with life
Our affinity for parks and wildlife
Keeping of pets
High value of real estate with views of natural lands
Nature deficit disorder = alienation from the natural environment
May be behind the emotional and physical problems of the young
evidence suggest that lack of contact also exacerbates ADD and violence
FIGURE 9.16
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34. Do we have ethical obligations toward other species?
Humans are part of nature and need resources to survive
Our ethics have developed from our intelligence and our ability to make choices
Many people feel that other organisms have intrinsic value and an inherent right to exist. This is reflected in “deep ecology” and the animal rights movement.
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35. Biophilia and nature deficit disorder
weighing the issues
Biophilia and nature deficit disorder
What do you think of the concepts of biophilia and “nature deficit disorder”?
Have you ever felt a connection to other living things that you couldn’t explain in scientific or economic terms?
Do you think that an affinity for other living things is innately human?
How could you determine whether or not most people in your community feel this way?
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36. Conservation biology arose in response to biodiversity loss
Conservation biology = devoted to understanding the factors that influence the loss, protection, and restoration of biodiversity
An applied and goal- oriented science
FIGURE 9.17
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37. Conservation biologists work at multiple levels
Use field data, lab data, theory, and experiments to study impacts of humans on other organisms
Design, test, and implement ways to mitigate impacts
Minimum viable population = how small a population can become before it runs into problems
Metapopulations = a network of subpopulations
Small populations are most vulnerable to extinction and need special attention
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38. Island biogeography theory
Equilibrium theory of island biogeography = explains how species come to be distributed among oceanic islands
Also applies to “habitat islands” – patches of one habitat type isolated within a “sea” of others
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
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39. Species richness results from island size and distance
Fewer species colonize an island far from the mainland
Large islands have higher immigration rates
Large islands have lower extinction rates
FIGURE 9.18
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40. The species-area curve
FIGURE 9.19
Large islands contain more species than small islands
They are easier to find and have lower extinction rates
They possess more habitats
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41. Small “islands” of forest rapidly lose species
Forests are fragmented by roads and logging
Small forest fragments lose diversity fastest
Starting with large species
Fragmentation is one of the prime threats to biodiversity
FIGURE 9.20
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42. Captive breeding, reintroduction, and cloning are single-species approaches
Captive breeding – individuals are bred and raised with the intent of reintroducing them into the wild
Zoos and botanical gardens
Some reintroductions require international cooperation
Whooping cranes in Wood Buffalo Park (Canada) and gulf coast of Texas (U.S.)‏
Some habitat is so fragmented, a species cannot survive once reintroduced
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43. Protecting biodiversity
Cloning – a technique to create more individuals and save species from extinction
Most biologists agree that these efforts are not adequate to recreate the lost biodiversity
Ample habitat and protection in the wild are needed to save species
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44. Fragmentation and biodiversity
weighing the issues
Fragmentation and biodiversity
Suppose a critic of conservation tells you that human development increases biodiversity, pointing out that when a forest is fragmented, new habitats, such as grassy lots and gardens, may be introduced to an area and allow additional species to live there.
How would you respond?
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45. Umbrella species
Conservation biologists use particular umbrella species as tools to conserve communities and ecosystems
helps protect less-charismatic animals
Flagship species – large and 'charismatic' species used as spearheads for biodiversity conservation
The World Wildlife Fund’s panda bear
Some organizations are moving beyond the single species approach to focus on whole landscapes
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46. Both national and international conservation efforts are widely supported
2002: Species at Risk Act stresses cooperation with landowners and governments to avoid hostility
COSEWIC (Committee on the Status of Endangered Wildlife in Canada) = expert committee that reports the status of species at risk
1973: UN Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) – protects endangered species by banning international transport of their body parts
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47. Other approaches highlight areas of high biodiversity
Biodiversity hotspots – prioritizes regions most important globally for biodiversity
Support a great number of endemic species = species found nowhere else in the world
The area must have at least endemic plant species (0.5% of the world total)‏
It must have lost 70% of its habitat due to human impact
FIGURE 9.22
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48. There are 34 global biodiversity hotspots
2.3% of the planet’s land surface contains 50% of the world’s plant species and 42% of all terrestrial vertebrate species
FIGURE 9.23
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49. Community- based conservation is increasingly popular
Community-based conservation = conservation biologists actively engage local people in protecting land and wildlife
Protecting land deprives people access to resources
Can guarantee that these resources will not be used up or sold to foreign corporations and can instead be sustainably managed
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50. Innovative economic strategies are being employed
Debt-for-nature swap = a conservation organization pays off a portion of a developing country’s international debt
In exchange for a promise by the country to set aside reserves
Fund environmental education, and
Better manage protected areas
Conservation concession = conservation organizations pay nations to conserve, and not sell, resources
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51. Conclusion
Loss of biodiversity threatens to result in a mass extinction
Primary causes of biodiversity loss are:
Habitat alteration, invasive species, pollution, overharvesting of biotic resources, and climate change
Human society cannot function without biodiversity’s pragmatic benefits
Science can help save species, preserve habitats, restore populations, and keep natural ecosystems intact
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52. QUESTION: Review
Which level is NOT included in the concept of biodiversity?
Species
Genetics
Ecosystems
All of the above are included in this concept
Answer: d
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53. QUESTION: Review
What happens when a species experiences “inbreeding depression”?
The species becomes too large for the resource base
Genetically similar parents mate and produce inferior offspring
Genetically similar parents mate and produce superior offspring
The number and variety of species increases
Answer: b
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54. QUESTION: Review Species richness increases towards the equator
According to the concept of “latitudinal gradient,” which of the following happens?
Species richness increases towards the equator
Species richness decreases towards the equator
Species richness decreases over time
Countries like Canada have many more species than expected
Answer: a
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55. QUESTION: Review
Which of the following is the major cause of extinction?
Invasive species
Pollution
Habitat loss
Overharvesting
Answer: c
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56. QUESTION: Review Biodiversity does all of the following, except…
Provide ecosystem services
Decrease food security
Maintain ecosystem function
Provide aesthetic benefits
Answer: b
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57. QUESTION: Review
According to the theory of island biogeography, which island would have the highest species richness?
A large island, close to the mainland
A large island, far from the mainland
A small island, close to the mainland
A small island, far from the mainland
Answer: a
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58. QUESTION: Review A “biodiversity hotspot” is…?
An area located near the equator
An area that supports few, but large, species
An area that contains naturally high numbers of people
An area that contains a large number of endemic species
Answer: d
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59. QUESTION: Interpreting Graphs and Data
Where would ecotourists go to view the maximum species richness on these islands?
a) Redonda
b) Montserrat
c) Puerto Rico
d) Hispaniola
Answer: d
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