Interdependence of Interdependence of Living Things Living Things The Biosphere The Biosphere Ecosystems and Communities Ecosystems and Communities Populations Populations Humans in the Biosphere Humans in the Biosphere
Dec 18, 2015
Interdependence of Interdependence of Living ThingsLiving Things
The BiosphereThe BiosphereEcosystems and CommunitiesEcosystems and Communities
PopulationsPopulationsHumans in the BiosphereHumans in the Biosphere
The BiosphereThe Biosphere
What is ecology?What is ecology?
Ecology – study of interactions among and Ecology – study of interactions among and between organisms and their environmentbetween organisms and their environment
Biosphere – contains the combined Biosphere – contains the combined portions of the earth in which all life existsportions of the earth in which all life exists 8 km above Earth’s surface 8 km above Earth’s surface 11 km below 11 km below
the ocean surfacethe ocean surface Levels of organization:Levels of organization:
Individual Individual population population community community ecosystem ecosystem Biome Biome Biosphere Biosphere
Ecological MethodsEcological Methods
Use a wide range of tools and techniquesUse a wide range of tools and techniques 3 basic approaches:3 basic approaches:
Observing –Observing –• What species live here? How many?What species live here? How many?
Experimenting –Experimenting –• Experiments can be set up in the laboratory or in natureExperiments can be set up in the laboratory or in nature• Tests a hypothesisTests a hypothesis
Modeling –Modeling –• Mathematical formulas are used to make predictions about Mathematical formulas are used to make predictions about
future events based on observations from the presentfuture events based on observations from the present
Energy flowEnergy flow
ProducersProducers Main form of energy on Earth = sunlightMain form of energy on Earth = sunlight Capture energy from sunlight (photosynthesis) or Capture energy from sunlight (photosynthesis) or
from chemical energy (chemosynthesis) = producersfrom chemical energy (chemosynthesis) = producers Autotrophs = capture energy from sunlight to make Autotrophs = capture energy from sunlight to make
food (photosynthesis)food (photosynthesis)
ConsumersConsumers Rely on other organisms for energy and food (cellular Rely on other organisms for energy and food (cellular
respiration) = “heterotrophs” or “consumers”respiration) = “heterotrophs” or “consumers”
Feeding RelationshipsFeeding Relationships Energy flows from producers to various heterotrophsEnergy flows from producers to various heterotrophs Food chainFood chain
Energy is transferred by eating and being eaten Energy is transferred by eating and being eaten Food webFood web
Links all the food chains in an ecosystem togetherLinks all the food chains in an ecosystem together Trophic levelTrophic level
Each step in a food chain or web Each step in a food chain or web Producers are the first trophic levelProducers are the first trophic level Consumers make up the 2Consumers make up the 2ndnd, 3, 3rdrd, or higher levels, or higher levels Each consumer depends on the level below for energyEach consumer depends on the level below for energy
Energy PyramidEnergy Pyramid
Only 10% of the Only 10% of the energy available energy available within one tropic level within one tropic level is transferred to the is transferred to the nextnext
The rest of the energy The rest of the energy is used during cellular is used during cellular processes and processes and escapes as heat!!!escapes as heat!!!
Biomass PyramidBiomass Pyramid
Total amount of living Total amount of living tissue within each tissue within each trophic leveltrophic level
grams of organic grams of organic matter/ unit areamatter/ unit area
Potential food for Potential food for each leveleach level
Pyramid of NumbersPyramid of Numbers
Number of Number of individuals at each individuals at each trophic leveltrophic level
Bioaccumulation• This happens when atop predator consumesorganisms that have asmall amount of toxinin their bodies, butover time, that toxinbuilds up to harmfullevels in the toppredator.
Toxins that do not follow theToxins that do not follow theflow of energy modelflow of energy model
BiomagnificationBiomagnification
• • This happens when This happens when anan
organism has a smallorganism has a small
amount of toxin in itsamount of toxin in its
system and whensystem and when
consumed, it passes allconsumed, it passes all
of that toxin to theof that toxin to the
next organism.next organism.
• • The cycle continuesThe cycle continues
up the food chain.up the food chain.
Biomass Pyramid & Food Chain Biomass Pyramid & Food Chain DesignDesign
On a piece of computer paper (use both sides)On a piece of computer paper (use both sides) Create Biomass pyramid using the Biome you Create Biomass pyramid using the Biome you
chose.chose. Use the organisms found in the description of Use the organisms found in the description of
your biome (in book) PRODUCERS your biome (in book) PRODUCERS CONSUMERS CONSUMERS
Create a Food Chain using the Biome you choseCreate a Food Chain using the Biome you chose Use the organisms found and start with a Use the organisms found and start with a
producer and finish with the highest level producer and finish with the highest level consumer!consumer!
Recycling in the BiosphereRecycling in the Biosphere
Matter is recycled within and between Matter is recycled within and between ecosystemsecosystems
Matter is not used up…it is transformed!!!Matter is not used up…it is transformed!!! Matter is recyled through biogeochemical Matter is recyled through biogeochemical
cycles:cycles: Water cycleWater cycle Nutrient cycles (carbon, nitrogen, Nutrient cycles (carbon, nitrogen,
phosphorus)phosphorus)
The Water CycleThe Water Cycle
Liquid Liquid gas (evaporation) gas (evaporation) Evaporation from plants = transpirationEvaporation from plants = transpiration Water is recycled through the BiopshereWater is recycled through the Biopshere 1 water molecule 1 water molecule 4000 years to 4000 years to
complete one cyclecomplete one cycle
Nutrient CyclesNutrient Cycles
Living things need nutrients to grow and Living things need nutrients to grow and carry out essential life functions.carry out essential life functions.
Nutrients are often in short supply in an Nutrients are often in short supply in an ecosystemecosystem ““Limiting Nutrients”Limiting Nutrients”
Recycling nutrients is vital to ecosystem Recycling nutrients is vital to ecosystem healthhealth
Prevents toxic concentrations of chemicalsPrevents toxic concentrations of chemicals
Nutrient CyclesNutrient Cycles
Add group notes on the various nutrient Add group notes on the various nutrient cycles here!cycles here!
Requirements:Requirements: Summarize the biogeochemical cycleSummarize the biogeochemical cycle Describe a piece of research that shaped Describe a piece of research that shaped
our understanding of the nutrient cycle our understanding of the nutrient cycle assigned (focus on Biological research).assigned (focus on Biological research).
Ecosystems and Ecosystems and CommunitiesCommunities
Homework:Homework:Chapter 4 (4-1 Chapter 4 (4-1 4-3 only) vocab 4-3 only) vocab
flashcardsflashcards
The Role of ClimateThe Role of Climate
Weather Weather day-to-day local condition of Earth’s day-to-day local condition of Earth’s atmosphereatmosphere
Climate Climate average, year-after-year condition of average, year-after-year condition of temperature and precipitation in a particular temperature and precipitation in a particular regionregion Factors include: trapping of heat by the atmosphere, Factors include: trapping of heat by the atmosphere,
the latitude, the transport of heat by winds and ocean the latitude, the transport of heat by winds and ocean currents, the amount of precipitation that results, the currents, the amount of precipitation that results, the shape and elevation of landmassesshape and elevation of landmasses
Energy of sunlight is the ultimate driver of climateEnergy of sunlight is the ultimate driver of climate
BiomesBiomes
Each biome is defined by a Each biome is defined by a unique set of:unique set of:
1.1. abiotic factors (particularly abiotic factors (particularly climate) climate)
2.2. a characteristic ecological a characteristic ecological communitycommunity
ClimatogramsClimatograms
Create a climatogram using data from Create a climatogram using data from South Kingstown RISouth Kingstown RI What biome do we belong to?What biome do we belong to?
Compare our climatogram to the Biome Compare our climatogram to the Biome you have been working with.you have been working with. Prompt: Prompt: Compare the climatogram for South
Kingstown (temperate forest biome) to the Biome you have been studying. How are they similar? How are they different? Use specific evidence to support your response.
The Greenhouse EffectThe Greenhouse Effect
Carbon dioxide, Carbon dioxide, methane, water methane, water vapor, and vapor, and other gases other gases Trap heat Trap heat
energy energy Maintains Maintains
Earth’s Earth’s temperature temperature rangerange
Effect of Latitude on ClimateEffect of Latitude on Climate
The Earth is tilted on its axis!The Earth is tilted on its axis! Solar radiation strikes different regions of the Earth’s Solar radiation strikes different regions of the Earth’s
surface at an anglesurface at an angle
THUS, Earth has 3 main climate zones:THUS, Earth has 3 main climate zones: Polar zone Polar zone very low angle (cold areas – 66.5 very low angle (cold areas – 66.5°° – –
9090°° N and S) N and S) Temperate zone Temperate zone angle changes over the year angle changes over the year
(warm and cold areas – 23.5(warm and cold areas – 23.5°° – 66.5 – 66.5°° N and S) N and S) Tropical zone Tropical zone nearly direct angle (always warm - 0 nearly direct angle (always warm - 0° °
- 23.5° N and S)- 23.5° N and S)
Heat Transport in the BiosphereHeat Transport in the Biosphere Unequal heating of Earth’s surface drives winds and Unequal heating of Earth’s surface drives winds and
ocean currentsocean currents Transport heat throughout the biosphereTransport heat throughout the biosphere
Wind currentsWind currents Warm air rises, cool air sinksWarm air rises, cool air sinks The prevailing (global) winds affects the climate in a given regionThe prevailing (global) winds affects the climate in a given region
Ocean currentsOcean currents Warm water rises, cool water sinksWarm water rises, cool water sinks The global ocean currents affects the climate of nearby The global ocean currents affects the climate of nearby
landmasseslandmasses LandmassesLandmasses
Mountain ranges can interfere with air mass movementMountain ranges can interfere with air mass movement Rain shadow effect Rain shadow effect one side is wet and the other dry one side is wet and the other dry
Biotic and Abiotic Factors that Biotic and Abiotic Factors that Shapes EcosystemsShapes Ecosystems
Biotic FactorsBiotic Factors Biological influences on organisms within an Biological influences on organisms within an
ecosystemecosystem Includes the entire living cast of characters with which Includes the entire living cast of characters with which
an organism might interactan organism might interact Abiotic FactorsAbiotic Factors
Physical or nonliving influences that shape Physical or nonliving influences that shape ecosystemsecosystems
Includes: temperature, precipitation, humidity, wind, Includes: temperature, precipitation, humidity, wind, nutrient availability, soil type, sunlightnutrient availability, soil type, sunlight
TOGETHER (Biotic and Abiotic factors)TOGETHER (Biotic and Abiotic factors) “Habitat” of an organism“Habitat” of an organism
The NicheThe Niche
The full range of biotic and abiotic The full range of biotic and abiotic conditions in which an organism lives and conditions in which an organism lives and uses those conditions.uses those conditions. Example: It’s place in the food web, the range Example: It’s place in the food web, the range
of temperatures needed for survival, etc.of temperatures needed for survival, etc. No 2 species can share the same niche!!!No 2 species can share the same niche!!!
Community InteractionsCommunity Interactions
Organisms interact constantly Organisms interact constantly shapes shapes ecosystemsecosystems
3 main types = 3 main types = CompetitionCompetition PredationPredation SymbiosisSymbiosis
• MutualismMutualism• CommensalismCommensalism• ParasitismParasitism
CompetitionCompetition
Occurs when a resource is being used at Occurs when a resource is being used at the same time in the same place.the same time in the same place.
Resource = any necessity of life (water, Resource = any necessity of life (water, nutrients, light, food, or space)nutrients, light, food, or space)
Often results in a winner and a loser.Often results in a winner and a loser. Competitive Exclusion Principle:Competitive Exclusion Principle:
No 2 species can occupy the same niche in No 2 species can occupy the same niche in the same habitat at the same time.the same habitat at the same time.
ANALYZE THE GRAPH: A red squirrel population is competing with a grey squirrel population…Who wins (the colors correspond to each squirrel type)? How do you know (use evidence to support your answer)?
PredationPredation Interaction where one organism captures Interaction where one organism captures
and feeds on another organismand feeds on another organism Predator = one that does the killingPredator = one that does the killing Prey = one that is being eatenPrey = one that is being eaten
SymbiosisSymbiosis Any relationship in which 2 species live closely together Any relationship in which 2 species live closely together
(3 main types)(3 main types) Mutualism:Mutualism:
Both species benefit from the relationshipBoth species benefit from the relationship Example = flower pollination by insectsExample = flower pollination by insects
Commensalism:Commensalism: One member of the relationship benefits and the other is neither One member of the relationship benefits and the other is neither
helped nor harmedhelped nor harmed Example = barnacles on whalesExample = barnacles on whales
Parasitism:Parasitism: One organism lives on (ectoparasite) or inside (endoparasite) One organism lives on (ectoparasite) or inside (endoparasite)
another organism and harms it.another organism and harms it. Example = fleas on a dogExample = fleas on a dog
Ecological SuccessionEcological Succession
Ecosystems constantly change in Ecosystems constantly change in response to natural and human response to natural and human disturbancesdisturbances
As an ecosystems changes As an ecosystems changes older older inhabitants gradually die out and new inhabitants gradually die out and new organisms move in = “ecological organisms move in = “ecological succession”succession” Primary successionPrimary succession Secondary successionSecondary succession
Primary SuccessionPrimary Succession
Succession that occurs on surface with NO soilSuccession that occurs on surface with NO soil Example = on newly formed volcanic rock or on Example = on newly formed volcanic rock or on
bare rock exposed when glaciers meltbare rock exposed when glaciers melt 11stst species to populate = pioneer species species to populate = pioneer species
Lichens (a fungus and an alga simbiontLichens (a fungus and an alga simbiont can live on can live on bare rock)bare rock)
When they die lichens help form soil that allows new When they die lichens help form soil that allows new organisms to move inorganisms to move in
Lichens Lichens mosses mosses grasses grasses shrubs shrubs trees trees• What types of animals would you see at each stage?What types of animals would you see at each stage?
Bare rock with lichens
Secondary SuccessionSecondary Succession
When a disturbance of some kind changes an When a disturbance of some kind changes an existing community WITHOUT removing the soilexisting community WITHOUT removing the soil
Example: land is cleared for farming, a wildfire Example: land is cleared for farming, a wildfire burns a woodlandburns a woodland
Myth of the climax community (a mature, stable Myth of the climax community (a mature, stable community that does not undergo further community that does not undergo further succession)succession) No community is ever at this pointNo community is ever at this point Climate change and human disturbances are always Climate change and human disturbances are always
at work.at work.
PopulationsPopulationsHomework: Ch.5 vocab flashcardsHomework: Ch.5 vocab flashcards
How Populations GrowHow Populations Grow
Characteristics of Populations:Characteristics of Populations: Geographic distribution (range) –Geographic distribution (range) –
• The area or range inhabited by a populationThe area or range inhabited by a population Population density –Population density –
• The number of individuals per unit areaThe number of individuals per unit area Growth rate –Growth rate –
• Determined by # of births, # of deaths, # Determined by # of births, # of deaths, # immigrated, # emigratedimmigrated, # emigrated
Age structure –Age structure –• The range of ages in a populationThe range of ages in a population
Population GrowthPopulation Growth
Factors that affect population size:Factors that affect population size: # of births # of births causes an increase in causes an increase in
population sizepopulation size # of deaths # of deaths causes a decrease in causes a decrease in
population sizepopulation size Immigration (the movement of individuals into Immigration (the movement of individuals into
an area) an area) causes an increase causes an increase Emigration (the movement of individuals out Emigration (the movement of individuals out
of an area) of an area) causes a decrease causes a decrease
Exponential GrowthExponential Growth
Exponential growth Exponential growth occurs when the occurs when the individuals in a population reproduce at a individuals in a population reproduce at a constant rateconstant rate
Occurs only under ideal conditions Occurs only under ideal conditions Abundant space and foodAbundant space and food Protected from predators and diseaseProtected from predators and disease
J-shaped curveJ-shaped curve
Logistic GrowthLogistic Growth
As resources become scarce, the growth of a As resources become scarce, the growth of a population slows or stopspopulation slows or stops Birth rate may decrease, death rate may increase, Birth rate may decrease, death rate may increase,
immigration may increase, emigration may decrease, immigration may increase, emigration may decrease, or any combination of these.or any combination of these.
Carrying capacity Carrying capacity the largest # of individuals the largest # of individuals that a given environment can supportthat a given environment can support
S-shaped curveS-shaped curve
Population TrendsPopulation TrendsFruit Fly Population Growth
Days # of fruit flies
5 10
10 50
15 100
20 200
25 300
30 310
35 320
40 320
Rabbit Population Growth
Generations # of rabbits
1 100
2 105
25 1000
37 1600
55 2400
72 3350
86 8000
100 13,150
1. Make a graph of each data table.
Population Trends: Data AnalysisPopulation Trends: Data AnalysisAnswer the following in your notebooks!!!Answer the following in your notebooks!!!
What type of growth pattern is exhibited by the What type of growth pattern is exhibited by the fruit fly population? Is it the same as the rabbit fruit fly population? Is it the same as the rabbit population? Explain.population? Explain.
Does either graph indicate there is a carrying Does either graph indicate there is a carrying capacity? If so…when? What is the maximum # capacity? If so…when? What is the maximum # of individuals that can be supported at one time?of individuals that can be supported at one time?
What might happen if a group of predators What might happen if a group of predators moved into the rabbits’ habitat during the 10moved into the rabbits’ habitat during the 10 thth generation and began eating rabbits?generation and began eating rabbits?
Limits to growthLimits to growth
Limiting Factors:Limiting Factors: In context of populationsIn context of populations A factor that causes population growth to decreaseA factor that causes population growth to decrease Density-dependent OR Density-independentDensity-dependent OR Density-independent
Examples that affect population size:Examples that affect population size: CompetitionCompetition PredationPredation Parasitism and diseaseParasitism and disease Drought and other climate extremesDrought and other climate extremes Human disturbancesHuman disturbances
Density-Dependent FactorsDensity-Dependent Factors
Depends on population sizeDepends on population size Factor only becomes limiting when the Factor only becomes limiting when the
population density reaches a certain levelpopulation density reaches a certain level Includes:Includes:
CompetitionCompetition PredationPredation ParasitismParasitism DiseaseDisease
CompetitionCompetition
When populations get crowded, they When populations get crowded, they compete for food, water, space, sunlight, compete for food, water, space, sunlight, and other essentials of life (resources and other essentials of life (resources become scarce).become scarce).
Major force behind evolutionary change!Major force behind evolutionary change! Can occur:Can occur:
Between members of the same speciesBetween members of the same species Between different speciesBetween different species
PredationPredation
In nature, populations are often controlled In nature, populations are often controlled by predatorsby predators
Predator-prey relationshipPredator-prey relationship Interactions that affect population growth of Interactions that affect population growth of
both predator and preyboth predator and prey Example:Example:
Remember the Wolf and deer population Remember the Wolf and deer population activityactivity
Parasitism and DiseaseParasitism and Disease
Parasites range in size Parasites range in size Similar to predatorsSimilar to predators
Take nourishment at the expense of the host Take nourishment at the expense of the host (causing disease and/or death)(causing disease and/or death)
Example: Example: WOW bug petsWOW bug pets They lay their eggs on a larvaThey lay their eggs on a larva The eggs hatch and consume the larvaThe eggs hatch and consume the larva
Density-Independent FactorsDensity-Independent Factors
Affects different populations the same way Affects different populations the same way regardless of population sizeregardless of population size
Examples include:Examples include: Unusual weatherUnusual weather Natural disastersNatural disasters Seasonal cyclesSeasonal cycles Human activity Human activity
Human Population GrowthHuman Population Growth
The size of the human population has grown over The size of the human population has grown over time.time.
Human Population VideosHuman Population Videos
World Population World Population growth from 1 A.D.growth from 1 A.D.Produced by Population Connection Produced by Population Connection in 2000. Population Connection is a in 2000. Population Connection is a nonprofit, 501(c)(3) organizationnonprofit, 501(c)(3) organizationhttp://www.youtube.com/watch?v=4BbkQiQyaY
Exponential Growth Exponential Growth lecturelectureDavid Suzuki “Forces of nature” David Suzuki “Forces of nature” – speaking about exponential – speaking about exponential growthgrowthhttp://www.youtube.com/watch?
v=Q9xoFCS33kg
Patterns of Human Population Patterns of Human Population GrowthGrowth
DemographyDemography Study of human populationsStudy of human populations
The Demographic TransitionThe Demographic Transition When population growth in a country has slowed in When population growth in a country has slowed in
response to industrialization.response to industrialization. Transition is complete when birthrate falls to meet Transition is complete when birthrate falls to meet
deathrate (population growth stops)deathrate (population growth stops)• More children survive to adulthood, more adults More children survive to adulthood, more adults
living to old ageliving to old age 33rdrd world countries have yet to undergo this process world countries have yet to undergo this process
Age StructureAge Structure Population profiles (# of people in different age groups)Population profiles (# of people in different age groups)
Humans in the Humans in the BiosphereBiosphere
Ch. 6 vocab flashcardsCh. 6 vocab flashcards
Earth as an IslandEarth as an Island
We share a limited resource baseWe share a limited resource base We all depend on the natural ecological We all depend on the natural ecological
processes that sustain these resourcesprocesses that sustain these resources Take the earth calculator test now…Take the earth calculator test now…
How many earth’s do you need if everyone How many earth’s do you need if everyone lived like you?lived like you?
Is it fair to use resources the way you do?Is it fair to use resources the way you do? What are some ways you could decrease What are some ways you could decrease
your impact?your impact?
Human Activities that have Human Activities that have transformed the Biospheretransformed the Biosphere
Hunting and gatheringHunting and gathering Subsistence hunting Subsistence hunting
AgricultureAgriculture Domestication of animals (overgrazing, increased Domestication of animals (overgrazing, increased
water use)water use) Traditional Traditional Modern Agriculture (increased Modern Agriculture (increased
irrigation, increased use of chemical fertilizers, new irrigation, increased use of chemical fertilizers, new types of farming equipment)types of farming equipment)
Green Revolution Green Revolution governments introduced new, governments introduced new, intensive farming techniques to increase yields. intensive farming techniques to increase yields.
• ““miracle strains”: improved harvestmiracle strains”: improved harvest• Monoculture: a single crop/species was planted to increase Monoculture: a single crop/species was planted to increase
yield yield
Industrial Growth and Urban Industrial Growth and Urban DevelopmentDevelopment
Certain kinds of industrial processes:Certain kinds of industrial processes: Pollute air, water, and soilPollute air, water, and soil
Dense human communities:Dense human communities: Produce wastes that must be disposed ofProduce wastes that must be disposed of
Suburban sprawl:Suburban sprawl: Consumes farmland and natural habitatsConsumes farmland and natural habitats
All place stress on plant and animal All place stress on plant and animal populations and on the biosphere’s life populations and on the biosphere’s life support systems!!!support systems!!!
The Tragedy of the CommonsThe Tragedy of the Commons
““Any resource that is open to everyone (air Any resource that is open to everyone (air or ocean) will eventually be destroyed or ocean) will eventually be destroyed because everyone can use it but no one is because everyone can use it but no one is responsible for preserving it.”responsible for preserving it.”
Constructed Response Prompt: Constructed Response Prompt: (On the provided handout - write approx. ½ - (On the provided handout - write approx. ½ -
1 page)1 page) In your opinion is the “tragedy of the In your opinion is the “tragedy of the
commons” true? Use evidence/quotes from commons” true? Use evidence/quotes from the reading to support your answer.the reading to support your answer.
Renewable vs. Nonrenewable Renewable vs. Nonrenewable ReourcesReources
Work with a partner.Work with a partner.Using your book or the computer:Using your book or the computer:
Generate a list of 10 renewable Generate a list of 10 renewable resources and 10 nonrenewable resources and 10 nonrenewable resources.resources.
Sustainable UseSustainable Use
With your partner choose one of the following With your partner choose one of the following resources:resources: LandLand ForestForest OceanOcean AirAir WaterWater
What are some ways to use these resources in a What are some ways to use these resources in a sustainable way?sustainable way? You have 20 minutes to put together a 1 minute You have 20 minutes to put together a 1 minute
presentation on the topic.presentation on the topic.
BiodiversityBiodiversity
““Sum total of the genetically based variety Sum total of the genetically based variety of all organisms in the biosphere”of all organisms in the biosphere”
One of the Earth’s greatest natural One of the Earth’s greatest natural resourcesresources
Includes:Includes: Ecosystem diversityEcosystem diversity Species diversitySpecies diversity Genetic diversityGenetic diversity
Threats to BiodiversityThreats to Biodiversity
Human Activity can reduce biodiversity by:Human Activity can reduce biodiversity by: Altering habitats through developmentAltering habitats through development Hunting species to extinction Hunting species to extinction Introducing toxic compounds into food websIntroducing toxic compounds into food webs
• Failing septic systems (our water quality lab!!!)Failing septic systems (our water quality lab!!!)• DDT (biological magnification)– Rachel Carson’s DDT (biological magnification)– Rachel Carson’s
book book Silent SpringSilent Spring Introducing foreign species into new Introducing foreign species into new
environments (invasive species)environments (invasive species)
Charting a Course for the FutureCharting a Course for the Future
2 major global phenomena affect the 2 major global phenomena affect the biosphere:biosphere: Ozone depletionOzone depletion
• UV light is a mutagen!UV light is a mutagen! Global WarmingGlobal Warming
• Caused by a natural warming trend Caused by a natural warming trend ANDAND Human Human activity!!!activity!!!