Concepts of Biology 2nd Edition

1. Chapter 40
Conservation
Biology
Lecture Outline
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2. 40.1 Conservation biology
 Conservation biology
 Goal of conserving natural resources for this
generation and all future generations
 Support of biodiversity for all species
 Helps reduce extinctions of species
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3. Biodiversity & Extinction
 Biodiversity – variety of life on Earth
 Between 10 and 50 million species may exist
 Of the described species, nearly 1,200 in the
United States and 40,000 worldwide are in
danger of extinction
 Endangered species is in peril of immediate
extinction throughout all or most of its range
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4. Genetic & Ecosystem Diversity
 Genetic diversity
 Variations among the members of a population
 The more diverse a population, the more likely they survive
 Ecosystem diversity
 Conserve species that play a critical role in an ecosystem
 Saving an entire ecosystem can save many species
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5. Landscape diversity
 Landscape diversity
 Ecosystems can be so fragmented that they are connected by
patches or strips of land that allow organisms to move from one
ecosystem to the other
 Distribution of Biodiversity
 Biodiversity is not evenly distributed throughout the biosphere
 Some regions of the world are called biodiversity hotspots
because they contain unusually large concentrations of species
 Exs: Madagascar, Great Barrier Reef in Australia, rainforests
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6. Medicinal & Agricultural Value
 Medicinal Value
 Most prescription drugs in the United States were
originally derived from living organisms
 Valued at over $200 billion
 Agricultural Value
 Crops such as wheat, corn, and rice are derived from
wild plants
 Biological pest controls (natural predators and
parasites) are often preferable to chemical pesticides
 Ladybugs, bats
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7. Figure 40.3 Direct value of diverse wildlife (Cont.)
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8. Consumptive Use Value
 Consumptive Use Value
 Most freshwater and marine harvests depend on the
catching of wild animals, such as crustaceans,
mammals, and fishes
 Provides a variety of other products that are sold in
the marketplace worldwide, including wild fruits and
vegetables, skins, fibers, beeswax, and seaweed
 Many trees in the natural environment are still felled
for their wood
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9. Ecological Value
 Biogeochemical Cycles Dispose of Waste
 Biodiversity contributes to workings of water, carbon,
phosphorus, and nitrogen cycles
 Natural Areas Provide Fresh Water, Prevent Soil
Erosion, and Regulate Climate
 Water-holding capacity of forests and wetlands reduces the
possibility of flooding
 Forests improve climate because they take up carbon dioxide
 Ecotourism Is Enjoyed by Many
 In U.S., people spend $4 billion each year on ecotourism
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10. Figure 40.4 Tourists (inset) love to visit natural ecosystems, such as
this forest, which has indirect value because of its water-holding
capacity and its ability to take up carbon dioxide
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11. Habitat Loss & Extinctions
 Of 1,880 threatened and endangered species in
U.S., habitat loss was involved in 85% of cases
 Other significant causes of extinction are introduction
of alien species, pollution, overexploitation, and
disease
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12. Figure 40.5A
Macaws, Ara macao,
and other species are
endangered for the
reasons graphed here
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Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Habitat loss
Alien species
Pollution
Overexploitation
Disease
0 20 40 60 80 100
% Species Affected
© Gunter Ziesler/Peter Arnold/Photolibrary

13. Non-native Species
 Alien species – nonnative members brought
into new ecosystems
 Introduced by
 Colonization – Europeans brought various familiar species
with them when they colonized new places
 Dandelions
 Horticulture and agriculture – Aliens now taking over vast
tracts of land have escaped from cultivated areas
 Kudzu is a vine from Japan that the U.S. Department of
Agriculture thought would help prevent soil erosion
 Accidental transport – Global trade and travel accidentally
bring many new species from one country to another
 Zebra mussels
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14. Figure 40.6A Kudzu, a vine from Japan, has displaced many native
plants in the southern United States
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15. 40.7 Pollution contributes to extinctions
 Exs. of Pollution
 Acid deposition – (or “Acid Rain”):Both sulfur dioxide
from power plants and nitrogen oxides in automobile
exhaust are converted to acids when they combine
with water vapor in the atmosphere
 Eutrophication – Lakes are also under stress due to
over-enrichment (excess nitrogen and phosphorus)
 Algae blooms occur and upon death, the decomposers break
down the algae, but in so doing, they use up oxygen
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16. Ozone & Organic Chemicals
 Ozone depletion – Ozone (O3) “shield” absorbs most of
the wavelengths of harmful ultraviolet (UV) radiation so
they do not strike the Earth
 Severe ozone shield depletion can impair crop and tree growth
and also kill plankton that sustain oceanic life
 Organic chemicals – Organic chemicals are used in
pesticides, dishwashing detergents, cosmetics & plastics
 Mimic the effects of hormones and, in that way, most likely harm
wildlife
 Solid waste disposal – plastic floating in the ocean
creates a danger to wildlife
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17.  http://www.youtube.com/watch?v=tnUjTHB1lvM
 http://www.youtube.com/watch?v=J-gqJAsXiKQ

22. Figure 40.7 (Top) Normal coral reef. (Bottom) Bleaching of a coral reef. A temperature
rise of only a few degrees causes coral reefs to “bleach” and become lifeless. As the
oceans warm and land recedes, coral reefs could move northward
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23. 40.8 Overexploitation
contributes to extinctions
 Overexploitation occurs when the number of individuals
taken from a wild population is so great that the
population becomes severely reduced in number
 Overexploitation accounts for 17% of extinctions
 U.N. Food and Agricultural Organization tells us that
humans have now overexploited 11 of 15 major oceanic
fishing areas
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24. 40.9 Disease contributes to extinctions
 Number of pathogens that cause diseases is on
the rise, threatening human health as well as
that of wildlife
 Pollution can weaken organisms so that they are
more susceptible to disease
 Example: Almost half of sea otter deaths along the
coast of California are now due to infectious diseases
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25. Figure 40.9
The Harlequin toad is near extinction due to a fungal pathogen
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26. 40.10 Habitat preservation:
Keystone Species
 Keystone species
 Species that influence the viability of a community,
although their numbers may not be excessively high
 Extinction of a keystone species can lead to other
extinctions and loss of biodiversity
 Ex: Grizzly bears in northwestern US and Canada
 Berry seed distribution, control populations of other animals
 Otters
 Keep populations of other species in check
 Bats
 Essential pollinators 40-26

27. Figure 40.10A Landscape preservation will help grizzly bears,
Ursus arctos horribilis, survive
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28. 40.11 Restoration Ecology
 Restoration ecology – seeks scientific ways to
return ecosystems to former state
 Three principles have so far emerged
 It is best to begin as soon as possible before remaining
fragments of the original habitat are lost
 Once the natural history is understood, it is best to use
biological techniques that mimic natural processes to bring
about restoration
 Goal is sustainable development, ability of an ecosystem to
maintain itself while providing services to human beings
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29.  The Everglades – southern Florida
 Vast sawgrass prairie, interrupted occasionally by a
hardwood tree island
 Beginning of 20th century, settlers began to drain land
to grow crops
 A restoration plan has been developed that will
sustain the Everglades ecosystem, while maintaining
the services society requires
 The Everglades is to receive a more natural flow of
water from Lake Okeechobee
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30. Figure 40.11
A variety of
animals make their
home in the
Everglades
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31. 40-31
Figure 40.12 These activities are characteristic of a sustainable society. Arrows point
inward to signify that these activities increase the carrying capacity of the Earth
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
multi-use farming
integrated pest
management
conservation
of water
mass transit and
energy-efficient
transportation
recycling and
composting
wetland, delta
preservation
and restoration
(farming): © Inga Spence/Visuals Unlimited; (wetland preservation):© Peter DeJong/AP Images; (recycling): © Jeffrey Greenberg/PhotResearchers, Inc.;(bus): Courtesy DaimlerChrysler;
(drip irrigation): ©Inga Spence/Visuals Unlimited; (integrated pest management): Courtesy V.Jane Windsor, Division of Plant Industry, Florida Department of Agriculture &Consumer Services

32. 40.13 Renewable Energy Sources
 Traditional renewable energy sources
 Hydroelectric plants
 Geothermal energy
 Wind power
 Solar energy
 In the future, biofuels may run power plants or
your car
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33. 40-33
Figure 40.13A Traditional sources of renewable energy
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hydropower dams Wind power
Solar panels on roof-top Sun-tracking mirrors of a solar
energy plant
(dam): © David L. Pearson/Visuals Unlimited;(wind power): © S.K. Patrick/Visuals Unlimited; (solar panels, roof): © Argus
Foto Archiv/Peter Arnold/Photolibrary; (solar energyplant): © Gerald and Buff Corsi/Visuals Unlimited

34. Connecting the Concepts:
Chapter 40
 Biodiversity includes genetic, ecosystem & landscape
diversity
 Organisms have medicinal, agricultural & ecological value
 Habitat loss & introduction of non-native species are
destructive
 Overexploitation, pollution & diseases contribute to
extinctions
 Importance of developing renewable energy sources
 Habitat preservation & restoration = sustainable
development
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