Posted: October 27th, 2022

Read the article and write 2 pages essay including few deatils from the chapters which are attacged below.

Read the article and write 2 pages essay including few deatils from the chapters which are attached below. I have posted a screenshot for further instructions and only some deatils are required from chapters to realte with the article.

Lecture Outlines

Don't use plagiarized sources. Get Your Custom Essay on

Just from $13/Page

Order Essay

Withgott | Laposata

Sixth Edition

ENVIRONMENT the science behind the stories

Chapter 3

Evolution, Biodiversity, and

Population Ecology

Lecture objectives

 Explain natural selection with evidence.
 Describe how evolution influences biodiversity.
 Discuss the causes of species extinctions, including

significant mass extinction events.
 List the levels of ecological organization.
 Predict the growth of a population based on its

characteristics.
 Assess a population’s logistic growth, carrying

capacity, and limiting factors.
 Identify efforts and challenges in biodiversity

conservation.
© 2018 Pearson Education, Inc.

 Hawaii’s geographic isolation in the middle of the
Pacific Ocean has created a cradle of

evolution.

 Half of the native bird species have gone extinct
since the 18th century, primarily due to human
influences.

 The aki is one of 18 living species of Hawaiian
honeycreepers that diverged from a single ancestral
species that reached Hawaii millions of years ago.
 Each species has its own set of unique

characteristics, such as bill shape.

 The aki has a distinctly curved bill that it uses to get
nectar from a similarly shaped flower.

 Hawaiian forests are under siege due to clearcutting
and non-native species introduction first by
Polynesian settlers, then European settlers.

Evolution: The Source of Earth’s Biodiversity

 A species is a classification of organism whose

members can interbreed and produce fertile
offspring.

 A population is a group of individuals within a
species that live in the same geographic area.

 Populations change over multiple generations as
genetic changes alter their physical and behavioral
characteristics, a process called evolution.
 Evolution originates in genes and often leads to

modifications in appearance or behavior.

Natural selection shapes organisms

 Evolution is driven by natural selection, a process

that favors certain inherited characteristics over
others, causing them to be passed on more
frequently.

 The idea of natural selection is based on three
observations:
 Organisms face a constant struggle to survive and

reproduce.
 Organisms tend to produce more offspring than can

survive to maturity.
 Individuals of a species vary in their attributes.

 The concept of natural selection was first proposed
in the 1850s by Charles Darwin and, independently
by Alfred Russel Wallace, two British naturalists.

 Attributes are passed from parent to offspring
through genes.
 Genes that lead to better reproductive success will

eventually evolve through the entire population. This
is called adaptation.

Selection acts on genetic variation

 Accidental changes in DNA, called mutations, give

rise to genetic variation in individuals.
 The mixing of genetic material through sexual

reproduction also generates variation.
 Natural selection can drive a feature in a particular

direction.

 The average bill length of the ‘i’iwi can shift
depending on the environment.
 An environment with flowers

with short nectar tubes would
favor short beaks.
 An environment with flowers

with long nectar tubes would
favor long beaks.

Selective pressures from the environment
influence adaptation
 Closely related species that live in different

environments tend to diverge in their traits.
 Different selective pressure → different adaptations

 Unrelated species living in similar environments in
separate locations may independently acquire
similar traits.
 Similar selective pressures.
 This is called convergent

evolution.
© 2018 Pearson Education, Inc.

Evidence of selection is all around us

 Humans have conducted selection under our own

direction, called artificial selection.
 Domesticated dogs, cats, and livestock

Understanding evolution is vital for modern
society
 Many medical advances have resulted from our

knowledge of evolution.
 How infectious diseases spread and gain or lose

potency.
 Tracking evolving strains of influenza, HIV, and other

pathogens.
 Detection of the evolution of antibiotic resistance in

bacteria.

Evolution generates biodiversity

 Biological diversity, or biodiversity, refers to the

variety of life across all levels.
 Species, genes, populations, and communities

 About 1.8 million species have been identified, but
the actual amount may be 3–100 million.

 The process by which new species are generated is
termed speciation.

Speciation produces new types of organisms

 Allopatric speciation occurs when

populations become physically
separated over a geographic
distance.

 When a mutation arises in an
organism of one of the populations,
it does not spread to the other.
 Eventually the populations grow so

different that they can no longer
mate.

We can infer the history of life’s diversification
by comparing organisms
 Scientists represent the

history of divergence with
phylogenetic trees.
 Constructed by analyzing

genes and external traits
of organisms

 Taxonomists group species into categories meant to
reflect evolutionary relationships.
 Related species are grouped into a genus, related

genera are grouped into families, etc.

Fossils reveal life’s long history

 A fossil is an imprint in stone of a dead organism.
 By dating the rock layers that

contain fossils, paleontologists
can learn when the organisms
lived.
 The body of fossils worldwide

is called the fossil record.
 The vast majority of species

that once lived have
disappeared due to
extinction.

Some species are especially vulnerable to
extinction
 Extinction occurs when the

environment changes more
rapidly than the species can
adapt.

 Small and narrowly
specialized populations are
the most vulnerable.
 For example, Hawaii’s native

birds and plants did not
evolve defenses against
mammal predators.

 Species that are endemic to a region, meaning they
occur nowhere else on the planet, are especially
vulnerable.
 If an event affects their region, it affects all members

of the species.
 Island-dwelling species are also at elevated risk of

extinction, because many have been isolated from
typical evolutionary pressures, such as the presence
of predators.

Earth has seen several episodes of mass
extinction
 Most extinction happens gradually, at a rate called

the background extinction rate.
 The Earth has seen at least five mass extinction

events that wiped out 50–95% of Earth’s species
each time.
 The most catastrophic was the Permian extinction,

250 million years ago.
 Causes can include volcanism, asteroid impact,

methane releases, and global warming.

 Today’s extinction rate is 100–1000 times higher
than the background rate, and rising.

 Causes stem from human population growth:
 Altering or destroying natural habitats
 Overhunting and overharvesting
 Pollution of air, water, and soil
 Introduction of non-native species
 Climate change

Review Questions

1. Broccoli is a type of vegetable created by human

farmers by breeding wild mustard plants for large
flower buds and stems. Both are the same species,
Brassica oleracea. What is this an example of?
a. Speciation
b. Artificial selection
c. Natural selection
d. Background extinction

Presenter
Presentation Notes
Answer: b

Review Questions
2. Which of these is an accurate statement regarding

extinction?
a. Most extinctions have occurred due to catastrophic

natural disasters.
b. Species are currently going extinct at a level

significantly below the background rate.
c. Species are currently going extinct at a level

significantly greater than the background rate.
d. The fossil record only contains evidence of a single

mass extinction event.

Presenter
Presentation Notes
Answer: c

Ecology and the Organism

 Ecology is the study of the interactions among

organisms and with their environments, and
includes many levels.

 The organism, a single
living thing

 A population, or group of
individuals of the same
species that live in the
same area

 A community includes all of the populations of
species that live and interact within an area.
 Community ecology studies these interactions.

 Ecosystems include communities and all of the
abiotic, or nonliving parts of the environment.
 Ecosystem ecology studies the flow of energy

and nutrients between the living and nonliving parts.

 The biosphere is the sum total of all living things
and habitats on the Earth.
 Landscape ecology examines how ecosystems,

communities, and populations are distributed across
the Earth.

Each organism has habitat needs

 Each organism has a relationship with its habitat,

the environment in which it lives.
 Rock, soil, leaf litter, plant life, etc.
 Depending on the species, a habitat may be a square

meter of soil, or many miles of land.
 Organisms thrive in certain habitats and not others,

creating patterns of habitat use.
 Mobile organisms are able to choose where they

live, a process called habitat selection.

Organisms have roles in communities

 An organism’s role in its community is its niche.
 Includes resource use and interaction with other

organisms
 Species with narrow niches are specialists.
 The ‘akiapōlā’au

specializes in digging
grubs out of trees.

 Species that can utilize
a wider variety of
resources are
generalists.

Population Ecology
 Population size, the number of organisms in an

area at a given time, will grow when resources are
abundant and natural enemies are few.
 Declines due to resource

loss, natural disaster, or
impacts from other
species
 The North American

passenger pigeon
declined and went extinct
due to overhunting.

 Population density describes the number of
individuals per unit area.

 Population distribution describes the spatial
arrangement of organisms within an area.
 Random distribution shows no particular pattern.
 Uniform distribution has individuals spaced evenly.
 Clumped distribution occurs when individuals

concentrate in certain areas.

 Sex ratio is the proportion of males to females.
 1:1 ratios are seen in monogamous species; ratios

vary in others.
 Age structure describes the number of individuals

of different ages within a population.
 This can help to predict whether a population will

grow or shrink in the near future.

Populations may grow, shrink, or remain stable

 Demographers, scientists who study population

change, track the four key population factors:
 Natality — Births within the population.
 Mortality — Deaths within the population.
 Immigration — Arrival of individuals from outside the

population.
 Emigration — Departure of individuals from the

population.
 A population’s rate of natural increase is

determined by subtracting the death rate from the
birth rate.

 The actual population growth rate includes the
effects of emigration and immigration:

(birth rate – death rate) + (immigration rate – emigration rate)

 Rates may be expressed per 1000 individuals per
year. These can be used in the formula.

 Growth rates may be expressed as percentages:
population growth rate x 100%

Unregulated populations increase by
exponential growth
 When a population increases by a fixed percentage

each year, it undergoes exponential growth.
 When graphed, these populations produce a

J-shaped curve.
 Exponential growth only

occurs in nature when a
population is small,
competition is minimal,
and environmental
conditions are ideal.

Limiting factors restrain growth

 Eventually, every population is constrained by

physical, chemical, and biological limiting factors in
the environment.
 These factors determine carrying capacity, the

maximum population size of a species that an
environment can sustain.

 Population growth slows
as it reaches the carrying
capacity. This produces
an S-shaped curve called
logistic growth.

 The Eurasian collared dove is a non-native species
that has reached carrying capacity in Florida, where
it was introduced.
 In other areas, its population grows slowly or

exponentially, depending on how recently it arrived.

The influence of some factors depends on
population density
 The density of a population can enhance or diminish

the effect of some limiting factors.
 Density-dependent factors rise and fall with

population density.
 Predation, disease

 Density-independent factors are unaffected by
population density.
 Temperature extremes, catastrophic natural disasters

Life history strategies vary among species

 The life history theory explains how natural

selection influences reproduction, survival and
lifespan.
 Differences in how species invest in reproduction,

parental care, and survival are depicted in
survivorship curves.

 Type III survivorship curves occur when species
produce many offspring, but do not care for them.
 Survival is due to chance.
 These are also called r-selected species, and do well

in changing and unpredictable environments.

 Type I survivorship curves are observed in species
that have few offspring, but invest heavily in their
survival.
 These are also called K-selected species, and are

found in stable environments.

Conserving Biodiversity

 Human development and resource extraction are

speeding the natural rate of environmental change
that affects populations.
 One example is introduced species, which displace or

kill native species.

Innovative solutions are working

 A wide variety of organizations work to protect land,

remove alien species, and restore native habitats.
 These efforts can create economic benefits, as

visitors are drawn to wildlife and natural areas.
 This is called ecotourism.
 Hawaii’s economy takes

in $12 billion annually
from more than 7 million
visitors per year.

Climate change poses an extra challenge

 As temperatures and rainfall patterns change, even

protected areas may be affected.
 The mountainous Hakalau Forest in Hawai’i is

predicted to experience an increase in the range of
malaria-carrying mosquitoes.

Review Questions
3. Which is a true statement about this graph?

a. This species is undergoing exponential growth.
b. Limiting factors are present for this species.
c. The carrying capacity for this species is apparent.
d. This is an example of a Type III survivorship curve.

Presenter
Presentation Notes
Answer: a

Slide Number 1

Lecture objectives

Slide Number 3
Slide Number 4
Slide Number 5

Evolution: The Source of Earth’s Biodiversity

Slide Number 7

Natural selection shapes organisms

Slide Number 9

Selection acts on genetic variation

Slide Number 11
Selective pressures from the environment influence adaptation
Slide Number 13

Evidence of selection is all around us

Understanding evolution is vital for modern society

Evolution generates biodiversity
Speciation produces new types of organisms

We can infer the history of life’s diversification by comparing organisms
Slide Number 19

Fossils reveal life’s long history

Some species are especially vulnerable to extinction
Slide Number 22
Earth has seen several episodes of mass extinction
Slide Number 24

Review Questions
Review Questions
Ecology and the Organism

Slide Number 28
Slide Number 29

Each organism has habitat needs
Organisms have roles in communities
Population Ecology

Slide Number 33
Slide Number 34

Populations may grow, shrink, or remain stable

Slide Number 36
Unregulated populations increase by exponential growth

Limiting factors restrain growth

Slide Number 39
The influence of some factors depends on population density

Life history strategies vary among species

Slide Number 42
Slide Number 43

Conserving Biodiversity
Innovative solutions are working
Climate change poses an extra challenge
Review Questions

Lecture Outlines

Withgott | Laposata

Sixth Edition

ENVIRONMENT the science behind the stories

Chapter 4

Species Interactions

and
Community Ecology

Lecture objectives

 Compare types of species interactions.
 Describe feeding relationships and energy flow

using food webs.
 Discuss characteristics of a keystone species.
 Characterize disturbance, succession, and

community change.
 Predict the impacts of an invasive species and

suggestion responses to it.
 Explain restoration ecology.
 Identify and describe terrestrial biomes of the world.

Central Case Study: Black and White and
Spread All Over: Zebra Mussels Invade the
Great Lakes
 In 1988, it was discovered that zebra mussels had

been introduced to the Great Lakes through ballast
water discharged from European ships.
 Within six years, they had spread into the Mississippi

River watershed, reaching 19 U.S. states.
 They currently are found in 30 states.

 The mussels spread quickly because they were free
of predators and parasites.

 The mussels impact humans by clogging water
intake pipes at factories and municipal water plants,
as well as damaging docks, fishing gear, and boats.
 They have cost the Great Lakes economies an

estimated $5 billion over the first 10 years.

 Zebra mussels also have ecological impacts,
including the consumption and depletion of
microscopic algae, protists, and cyanobacteria
called plankton.
 The tiny aquatic animals that eat phytoplankton,

called zooplankton, are becoming depleted due
to a lack of food.

 Native mussels are
becoming suffocated by
the zebra mussels.

 The zebra mussel population may have peaked,
however, due to other changes in the ecology of the
Great Lakes.
 The quagga mussel (Dreissena bugensis) is another

invasive species that is competing with zebra
mussels.
 Native fish, crabs, ducks, and other predators are

beginning to use the mussels as a food source.

Species Interactions
 Species like zebra mussels interact with their

ecological community in many ways.
 Organisms that seek the same resource have a

relationship called competition.
 Intraspecific competition takes place between

members of the same species.
 Interspecific competition takes place between

members of different species.
 Competition becomes more intense when

populations are more dense.

 If one species is a stronger competitor, it may
exclude other species from the resource. This is
competitive exclusion.
 Zebra mussels had this effect on native mussels.

 Otherwise, if no single competitor excludes others,
species live side-by-side. This is species
coexistence.

 Coexisting species will alter their behaviors to
minimize competition, altering their niche.
 A niche is a species role in an ecosystem, including

resource use, habitat use, food consumption, and
other attributes.

 The full potential niche of a species is called its
fundamental niche.

 An individual that only plays part of its role due to
competition or other interactions has a realized
niche.
 The quagga mussel is pushing the zebra mussel into

from a fundamental to a realized niche.

 Over many generations, natural selection may favor
resource partitioning, where individuals use
shared resources in different ways.
 This may lead to

character displacement,
where competing species
diverge and develop
different characteristics.

Predators kill and consume prey

 Predation is the process by which individuals of one

species (the predators) capture, kill, and consume
individuals of another (the prey).

 Predation may
affect population
dynamics, such as
when an increase
in prey favors an
increase in
predators and
vice-versa.

 Predators that are better at capturing prey will live
longer and reproduce more. Natural selection will
favor adaptations that enhance hunting.

 Prey have the risk of death as a selective pressure,
causing the evolution of many types of defenses.

Parasites exploit living hosts

 Parasitism is a relationship where one organism

depends on the other for nourishment.
 Parasitism, unlike predation, usually does not result in

an organism’s death.
 Parasites live with their hosts in many ways:
 Inside the host, such as tapeworms
 On the host’s exterior, such as sea lampreys
 Free-living, such as cuckoos, who lay their eggs in the

nests of other species

 Parasites that cause disease are called pathogens.
 Pathogens can be protists (malaria), bacteria

(tuberculosis), or viruses (hepatitis).
 Parasites and hosts adapt and counter-adapt to

each other through a process called coevolution.

Herbivores exploit plants

 In herbivory, animals feed on the tissues of plants.
 Insects are the most common type of herbivore.

 Plants have also evolved defenses, such as toxic
chemicals, thorns, spines, or irritating hairs.

Mutualists help one another

 Mutualism is a relationship where two or more

species benefit each other.
 Many mutualistic relationships occur as part of

symbiosis – a close physical association between
species.
 Others, such as in

pollination, only require
free-living organisms
to encounter each
other once.
 Birds or insects transfer

pollen from flower to
flower, causing fertilization.

Review Questions

1. Two different bird species compete for the same

kinds of insects. One is more active in the morning,
the other in the evening. What is this an
example of?
a. Intraspecific competition
b. Resource partitioning
c. Competitive exclusion
d. Herbivory

Review Questions
2. Microbes are found in the digestive tract of all

humans. They are given a place to live and help to
digest our food. What type of relationship is this?
a. Interspecific competition
b. Parasitism
c. Herbivory
d. Mutualism

Ecological Communities

 A community is an assemblage of populations

organisms living in the same area at the same time.
 Community ecologists study which species coexist,

how they interact, how communities change over
time, and why these patterns occur.

 Some of the most important interactions among
community members involve who eats whom.

Energy passes among trophic levels

 Species in a community are given a rank within the

feeding hierarchy, called a trophic level.
 Producers use photosynthesis or chemosynthesis

to make their own sugars.
 Primary consumers consume producers.

 Secondary consumers prey
on primary consumers.

 Tertiary consumers prey on
secondary consumers.

 Detritivores scavenge waste
and dead bodies.

 Decomposers break down
nonliving matter into smaller
molecules.
 These play an especially

important role in cycling
nutrients back into soil for
plants to use.

Energy, numbers, and biomass decrease at
higher trophic levels
 At each trophic level, most of the energy input is

either used for maintenance or lost as heat.
 Trophic levels will only have about 10% of energy

content, organisms, and biomass compared to the
one below them.

 Biomass is the collective mass of living matter in a
given place and time.
 The pyramid pattern of energy and biomass illustrates

why eating at lower trophic levels decreases your
ecological footprint.

Food webs show feeding relationships and
energy flow
 The flow of energy and feeding relationships from

lower to higher trophic levels is depicted in a food
chain.

 Food webs incorporate all of the interlinking food
chains within an entire community, showing the map
of energy flow.

Some organisms play outsized roles

 A species that has an impact far greater than its

abundance is called a keystone species. Keystone
species can include:
 Decomposers that recycle nutrients and replenish the

soil.
 “Ecosystem engineers,” such as beavers and prairie

dogs, who physically alter ecosystems.
 Top predators, who control populations of lower

trophic level consumers, are often keystone species.

 If top predators are lost, primary consumers will
overconsume producers and alter the entire
ecosystem. This is called a trophic cascade.
 This is one example of a disturbance.

Communities respond to disturbance in various
ways
 A disturbance is any event that has rapid and

drastic effects on the community and ecosystem.
 Disturbances can be small and localized, such as a

tree falling and creating a gap in the forest canopy.
 Disturbances can be large, like hurricanes.
 Disturbances may also recur regularly, such as prairie

fires or insect outbreaks.
 A community that resists change and remains stable

shows resistance to the disturbance.
 A community that is changed by a disturbance but

Succession follows severe disturbance

 Severe disturbances may eliminate all or most of the

species in a community, initiating a series of
changes called succession.

 Succession begins with the colonization of pioneer
species.
 Pioneer species, such as grasses and forbs, spread

over long distances easily and are adapted for
growing quickly.

 Over time, pioneers are overtaken by longer-living
climax community species, such as hardwood
trees.

 Primary succession occurs when a disturbance
removes all plant or soil life.
 Lichens secrete acids that break down rock,

beginning the process of soil formation.

 Secondary succession begins with a disturbance
that alters the community but leaves the soil life
intact.
 Farming, fires, storms, and landslides are examples.

Communities may undergo shifts

 Communities do not pass through the stages of

succession evenly; ecological conditions may
promote or inhibit progression.

 At times, communities may undergo a regime shift,
meaning that the entire character of the community
changes from the disturbance.
 Occurs from climate change, loss of a keystone

species, or introduction of an invasive species.
 In some cases, human disturbance is causing

no-analog communities, which are mixtures of
species that have not previously occurred on the
Earth.

Invasive species pose threats to community
stability
 Introduced species are non-native arrivals to a

community brought by people.
 Most fail to establish populations, but the ones that

thrive are called invasive species.
 Introduced species become invasive when limiting

factors that normally regulate their population growth
are absent.
 Lack of competition, predators, or parasites.

 Zebra mussels became invasive and had both
positive and negative impacts on communities.

 Both zebra and quagga mussels have spread
throughout the waterways of North America.

We can respond to invasive species with
control, eradication, or prevention
 The problems caused by zebra and quagga mussels

led to the passage of the National Invasive Species
Act of 1996.
 Ships must dump their freshwater ballast at sea and

replace it with saltwater before entering the Great
Lakes.

 Funding has been provided for control measures:
 Applying toxic chemicals, heat, sound, electricity, UV

light, and carbon dioxide to stress the mussels.
 Control and eradication has been very expensive, so

Altered communities can be restored

 Scientists who study restoration ecology devise

ways to restore altered areas to their condition
before industrialized civilization.

 Ecological restoration may have two aims:
 Restore the functionality of an ecosystem.
 Return a community to its “pre-settlement” condition.

 Nearly all the U.S. tallgrass prairie has been
removed for farmland. A 1000-acre area near
Chicago has been restored with native vegetation.

 In Florida, dams, canals, and levees are being
undone to restore the natural water flow to the
Everglades.

 Invasive species, such as garlic mustard and
Burmese pythons, have also been removed from
these areas.

Review Questions
3. Which is an example of a secondary consumer in

this food web?
a. White-tailed deer
b. Deer mouse
c. Eastern cottontail
d. Rat snake

Review Questions
4. A forest fire destroys most of the animal and plant

life in a community. The soil and soil life are intact.
Within several decades, most of the original
community has been restored. What is this an
example of?
a. A disturbance.
b. Primary succession
c. Secondary succession
d. A and B
e. A and C

Earth’s Biomes

 Despite communities being in very different locations

in the Earth, they often have similar structure and
function.

 A regional complex of similar communities is called a
biome.
 Biomes are classified primarily by dominant plant type

and vegetation structure, which in turn is the result of
climate.

Climate helps determine biomes

 Temperature and precipitation exert the greatest

influence over all other climatic factors.

 Temperature and precipitation are highly correlated
with latitude, creating global patterns of biomes.

 Climate also varies with elevation. At higher
altitudes:
 Temperature, atmospheric pressure, and oxygen

decline.
 Ultraviolet radiation increases.

 Mountains also affect climate through the
rainshadow effect.
 When moist air rises a steep slope, it cools and

condenses, releasing precipitation.
 The air that reaches the other side of the mountain is

now very dry, creating an arid region.

 Climate diagrams, also called climatographs, depict
seasonal changes in temperature and precipitation
and help to tell the story of a biome.

 Temperate deciduous forests, for example, are
found at mid-latitudes and have relatively even
precipitation throughout the year.
 Winters are frozen, causing the trees to drop their

leaves.

 Temperature differences between winter and
summer are more extreme and rainfall diminishes in
temperate grasslands.
 These biomes are also known as prairie or steppe.

 Temperate rainforests are rich in rainfall, but still
found in mid-latitudes.
 Mostly contain coniferous trees.
 Soils are fertile, but susceptible to erosion if the

forests are cleared.

 Tropical rainforests have dark, damp interiors, lush
vegetation, and highly diverse communities.
 High numbers of trees species intermixed at low

densities.
 Acidic soils that are low in organic matter.

 Tropical dry forests have wet and dry seasons that
each occupy about half of the year.
 Temperature is consistently warm.
 Leaves are shed during the dry season.

 Savannas are tropical grassland interspersed with
acacias or other trees.
 Found in dry tropical areas, including parts of Africa,

Australia, and India.
 Distinct wet and dry seasons.

 Deserts are the driest biome, receiving less than
25 cm of rain per year.
 Soils have high mineral and low organic matter

content.
 Animals and plants must adapt to minimize water

loss.

 Tundras are also very dry, but are consistently cold
all year.
 Underground soil is permanently frozen, called

permafrost.
 Tundras are unoccupied by humans, but are the most

directly impacted by air pollution and climate change.

 Boreal forests, also called taiga, are also cold, but
receive more precipitation than tundras.
 They are dominated by few species of evergreen

trees.
 Soils are acidic and nutrient-poor.

 Chaparral is only found in a few small patches
throughout the world.
 Covered by a dense thicket of evergreen shrubs.
 Mild, wet winters and warm, dry summers.
 Fires are frequent.
 Climate is induced by nearby oceans.

Review Questions
5. Which is a true statement regarding this

climatograph?
a. There are seasonal shifts in temperature.
b. There are seasonal shifts in precipitation.
c. There are seasonal shifts in both temperature and

precipitation.
d. None of the above.

Review Questions
6. What type of biome is depicted by this

climatograph?
a. Tropical rainforest
b. Tropical dry forest
c. Temperate grassland
d. Desert

Slide Number 1

Lecture objectives

Central Case Study: Black and White and Spread All Over: Zebra Mussels Invade the Great Lakes
Slide Number 4
Slide Number 5
Slide Number 6

Species Interactions

Slide Number 8
Slide Number 9
Slide Number 10

Predators kill and consume prey

Slide Number 12

Parasites exploit living hosts

Slide Number 14

Herbivores exploit plants
Mutualists help one another
Review Questions
Review Questions
Ecological Communities
Energy passes among trophic levels

Slide Number 21
Energy, numbers, and biomass decrease at higher trophic levels
Slide Number 23
Food webs show feeding relationships and energy flow
Slide Number 25

Some organisms play outsized roles

Slide Number 27
Communities respond to disturbance in various ways

Succession follows severe disturbance

Slide Number 30
Slide Number 31

Communities may undergo shifts

Invasive species pose threats to community stability
Slide Number 34
Slide Number 35
We can respond to invasive species with control, eradication, or prevention

Altered communities can be restored

Slide Number 38
Slide Number 39
Slide Number 40

Review Questions
Review Questions
Earth’s Biomes
Climate helps determine biomes

Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56

Review Questions
Review Questions

Expert paper writers are just a few clicks away

Place an order in 3 easy steps. Takes less than 5 mins.

Calculate the price of your order

Type of paper needed:

Pages:

You will get a personal manager and a discount.

Academic level:

We'll send you the first draft for approval by at

Total price:

$0.00