chapter 17 biological resources. biological diversity biological diversity number, variety and...
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Chapter 17Chapter 17Biological ResourcesBiological Resources
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Biological DiversityBiological Diversity
Biological DiversityBiological Diversity Number, variety and variability of Number, variety and variability of
Earth’s organismsEarth’s organisms 3 Kinds of Biological Diversity:3 Kinds of Biological Diversity:
Genetic diversity Genetic diversity Species richnessSpecies richness Ecosystem diversityEcosystem diversity
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Why We Need OrganismsWhy We Need Organisms
Example contributions to human life:Example contributions to human life: FoodFood ClothingClothing ShelterShelter Pollination of cropsPollination of crops Antibiotics and medicinesAntibiotics and medicines Biological processes (nitrogen fixation)Biological processes (nitrogen fixation) Ethical/aestheticEthical/aesthetic
Biological Diversity represents an Biological Diversity represents an untapped resource for future usesuntapped resource for future uses
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Examples of Contributions:
Cinchona Tree Treatment for malaria from 1600’s until 1940’s Also for arthritis, lupus, and other diseases
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Examples of Contributions
Aspirin
Coca leaves
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Ecosystem Services and Ecosystem Services and Species RichnessSpecies Richness All organisms are All organisms are
interrelatedinterrelated Ecosystem servicesEcosystem services
Removal of a species Removal of a species from a community from a community can __________ can __________ ecosystem servicesecosystem services
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Scientific Importance of Scientific Importance of Genetic DiversityGenetic Diversity Genetic EngineeringGenetic Engineering
Provided:Provided: New vaccinesNew vaccines More productive farm animalsMore productive farm animals Agricultural plants with desirable Agricultural plants with desirable
characteristicscharacteristics
Depends on genetic diversity (cannot Depends on genetic diversity (cannot create genes)create genes) Important to protect this diversityImportant to protect this diversity
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Medical Importance of Medical Importance of OrganismsOrganisms Genetic Resources Genetic Resources
are important to are important to pharmaceutical pharmaceutical industryindustry Rosy Periwinkle – Rosy Periwinkle –
Cancer drug Cancer drug Aquatic sponge – Aquatic sponge –
AIDS drugAIDS drug
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Importance of OrganismsImportance of Organisms
Agricultural ImportanceAgricultural Importance Numerous species that are nutritionally Numerous species that are nutritionally
superior to the food we eatsuperior to the food we eat Industrial ImportanceIndustrial Importance
Industry depends on products from Industry depends on products from organismsorganisms Oils and lubricantsOils and lubricants Paper and lumberPaper and lumber
Ethical and Aesthetic ImportanceEthical and Aesthetic Importance
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ExtinctionExtinction
5 great mass extinctions mark boundaries of geologic time periods
NOW- 6th great mass extinction
Background extinctionBackground extinction
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Main Causes of Species Main Causes of Species DeclineDecline• E. O. Wilson uses the acronym E. O. Wilson uses the acronym HIPPOHIPPO to list to list
them:them:
• Consider the words of Nobel Peace Prize Consider the words of Nobel Peace Prize laureate (2004), Ms. Wangari Maathai of laureate (2004), Ms. Wangari Maathai of Kenya: “Protecting the global Kenya: “Protecting the global environment is directly related to environment is directly related to securing peace”securing peace”
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Major drivers of Major drivers of endangermentendangerment
From Wilcove 1996
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Endangered and Threatened Endangered and Threatened SpeciesSpecies Earth’s biological diversity is Earth’s biological diversity is
disappearing at an unprecedented ratedisappearing at an unprecedented rate Endangered SpeciesEndangered Species
Species that faces threats that may cause it Species that faces threats that may cause it to become extinct within a short periodto become extinct within a short period
Threatened SpeciesThreatened Species Species whose population has declined to Species whose population has declined to
the point that it may be at risk of extinctionthe point that it may be at risk of extinction
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Endangered & Extinct Endangered & Extinct SpeciesSpecies
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Endangered & Extinct Endangered & Extinct SpeciesSpecies
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Species with highly Species with highly specific resource specific resource requirements are requirements are particularly vulnerable particularly vulnerable to habitat alterations to habitat alterations
Endemic speciesEndemic species A species confined to A species confined to
the limited area in the limited area in which it evolved, which it evolved, often by resource often by resource requirementsrequirements
Current Threats to SpeciesCurrent Threats to Species
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•Labrador duck - from North Atlantic coast;disappeared between 1850 and 1870; disappearedas a result of changes to coastal habitat
•Heath hen - an eastern prairie grouse; lived inwoodland clearings from New England to theCarolinas; killed for high market value; most goneby 1915 and last sighted on Martha’s Vineyard (anisland off the Mass. coast) in 1932
•Great Auk - big penguin-like bird of islands andcoast of North Atlantic; killed for meat then asprized rare specimens; last pair killed in 1844
•Carolina parakeet - only member of parrot family in U.S.; in rivers and swamps of SE U.S.; killed andtrapped because of destruction to orchards; lastdied in Cincinnati Zoo in 1914 (same as pigeon)
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Passenger Pigeon-extinct
MARTHALast of her species, died at 1 p.m.,1 September 1914, age 29, in the
Cincinnati Zoological Garden.EXTINCT
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American Bison-
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Characteristic of Characteristic of Endangered SpeciesEndangered Species Extremely small (localized) rangeExtremely small (localized) range Requiring a large territoryRequiring a large territory Living on an islandLiving on an island Having a low reproductive successHaving a low reproductive success Small population size Small population size Low reproductive ratesLow reproductive rates Requiring specialized breeding areasRequiring specialized breeding areas Having specialized feeding habitatsHaving specialized feeding habitats
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California CondorCalifornia Condor
Scavenger birdScavenger bird Requires large, Requires large,
undisturbed territoryundisturbed territory 1983 - 22 birds1983 - 22 birds 1987–1992 - no 1987–1992 - no
longer found in longer found in naturenature
1992 - reintroduced 1992 - reintroduced to nature from zoosto nature from zoos
Currently - 200 Currently - 200 condors in naturecondors in nature
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Where is Declining Where is Declining Biological Diversity the Biological Diversity the Greatest Problem?Greatest Problem? Concern throughout the USConcern throughout the US US- Most serious in:US- Most serious in:
Hawaii (63% of species at risk)Hawaii (63% of species at risk) California (29% of species at risk)California (29% of species at risk)
Globally - Most serious in tropical rain Globally - Most serious in tropical rain forestsforests South and Central AmericaSouth and Central America Central AfricaCentral Africa SE AsiaSE Asia
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Earth’s Biodiversity Earth’s Biodiversity HotspotsHotspots
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Causes of Declining Causes of Declining BiodiversityBiodiversity
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Human Cause - Land Use Human Cause - Land Use ChangeChange Destruction, fragmentation or Destruction, fragmentation or
degradation of habitatsdegradation of habitats Little habitatLittle habitat
remains forremains formanymanyendangeredendangeredspeciesspeciesLast one shot
in CA 1922
Is there anything strange about our
state flag??
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Human Cause - Invasive Human Cause - Invasive SpeciesSpecies
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Introduced Snake on Guam
9 of the 11 species of native forest-dwelling birds have been extirpated from Guam. Five of these were endemic at the species
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Left: Illegal Trade in Products Made From Endangered Species
Right: Illegal Animal Trade - Green Parrots from the Amazon Rainforest
Human Cause- Human Cause- OverexploitationOverexploitation
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Human Cause - PollutionHuman Cause - Pollution
Examples: Acid rain, ozone depletion, Examples: Acid rain, ozone depletion, climate warming, excessive fertilizer, climate warming, excessive fertilizer, industrial wastesindustrial wastes
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Case-In-PointCase-In-PointDisappearing FrogsDisappearing Frogs
Amphibians are Amphibians are indicator speciesindicator species 168 Amphibian 168 Amphibian
species have gone species have gone extinct in last 2 extinct in last 2 decadesdecades
No single cause has No single cause has been identifiedbeen identified
Deformities have also Deformities have also been identified (right)been identified (right)
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Conservation BiologyConservation Biology
Scientific study of how humans impact Scientific study of how humans impact organisms and the development of organisms and the development of ways to protect biodiversityways to protect biodiversity
Involves:Involves: Protecting habitatsProtecting habitats Restoring damaged or destroyed habitatsRestoring damaged or destroyed habitats Zoos, aquaria, botanical gardensZoos, aquaria, botanical gardens Seed banksSeed banks
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Challenges in Conservation Challenges in Conservation ManagementManagement
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Fragmented HabitatsFragmented Habitats
Habitat Habitat separated by separated by roads or other roads or other human human developmentdevelopment
Habitat Habitat corridorscorridors - - allow animals to allow animals to move from one move from one fragment to fragment to another safelyanother safely
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Restoring Damaged Restoring Damaged HabitatsHabitats Restoration ecologyRestoration ecology
Study of the historical condition of a Study of the historical condition of a human-damaged ecosystemhuman-damaged ecosystem
Goal is to return it to its former stateGoal is to return it to its former state BenefitsBenefits
Creates biological habitatsCreates biological habitats Regeneration of soil damaged by Regeneration of soil damaged by
agriculture or miningagriculture or mining DisadvantagesDisadvantages
ExpensiveExpensive Take a long time to restore an areaTake a long time to restore an area
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Left: (1935) Early Left: (1935) Early stages of prairie stages of prairie restorationrestoration
Right: (current Right: (current day) restored day) restored prairieprairie
Restoring Damaged Restoring Damaged HabitatsHabitats
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Zoos, Aquaria and Botanical Zoos, Aquaria and Botanical GardenGarden Save organisms Save organisms
from extinctionfrom extinction Artificial inseminationArtificial insemination Embryo transferEmbryo transfer Surrogate mothers Surrogate mothers
(right)(right) Goal is to Goal is to
reintroduce reintroduce organisms back to organisms back to their natural habitattheir natural habitat
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Seed BanksSeed Banks
Stored seeds are Stored seeds are safe from habitat safe from habitat destruction, destruction, climate warming, climate warming, etc.etc.
reintroduce reintroduce extinct plant extinct plant speciesspecies
Some seeds Some seeds cannot be storedcannot be stored
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Endangered Species Act (ESA) Endangered Species Act (ESA) 19731973 Authorized protection of endangered Authorized protection of endangered
and threatened speciesand threatened species Currently 1300 species are listed in USCurrently 1300 species are listed in US
Left: Endangered Left: Endangered Species, the Florida Species, the Florida PantherPanther
Conservation Policies and Conservation Policies and LawsLaws
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Conservation Policies and Conservation Policies and LawsLaws Endangered Species Act Endangered Species Act
(continued)(continued) Species are designated as endangered or Species are designated as endangered or
threatened based on biological groundsthreatened based on biological grounds Controversial LegislationControversial Legislation
No compensation for private property owners No compensation for private property owners who suffer financial losswho suffer financial loss
Was not reauthorized in 1992 as Was not reauthorized in 1992 as scheduledscheduled Private property rights vs. conservationPrivate property rights vs. conservation
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Conservation Policies and Conservation Policies and LawsLaws Habitat Conservation PlansHabitat Conservation Plans
1982 Amendment to ESA1982 Amendment to ESA Resolved conflicts between development Resolved conflicts between development
interests and species protectioninterests and species protection International Conservation:International Conservation:
World Conservation Strategy (1980)World Conservation Strategy (1980) Convention on Biological DiversityConvention on Biological Diversity Convention on International Trade and Convention on International Trade and
Endangered Species of Wild Flora and Fauna Endangered Species of Wild Flora and Fauna (CITES) (1975)(CITES) (1975)
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Wildlife ManagementWildlife Management
Application of conservation principles to Application of conservation principles to manage wild species and their habitats manage wild species and their habitats for human benefit or for the welfare of for human benefit or for the welfare of other speciesother species
Different priorities than conservation Different priorities than conservation biologybiology Wildlife managers concerned with common Wildlife managers concerned with common
speciesspecies Conservation biologist concerned with Conservation biologist concerned with
threatened or endangered speciesthreatened or endangered species
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Wildlife ManagementWildlife Management
Migratory AnimalsMigratory Animals Ex: Artic Snow Geese - increase in Ex: Artic Snow Geese - increase in
population has damaged much of Arctic population has damaged much of Arctic fragile coastal ecosystem (below)fragile coastal ecosystem (below)
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Wildlife ManagementWildlife Management
Aquatic OrganismsAquatic Organisms Must be managed to ensure they are not Must be managed to ensure they are not
overexploitedoverexploited Freshwater fishesFreshwater fishes
Laws regulate time of year, size of fish Laws regulate time of year, size of fish and maximum allowable catchand maximum allowable catch
Ocean fishesOcean fishes Ocean fisheries often viewed as Ocean fisheries often viewed as
common propertycommon property