Umich Environ 201- Benedict Midterm

CASE STUDY: What are the lessons of Easter Island (pgs 8-9)?

- Deforestation of Easter Island led to a grave situation where species died out in both the flora and fauna

- This deforestation was caused by rats that were brought on ships from other places, the rats ate so much of the nuts that the

trees could not regenerate and eventually caused them to die out

- The original inhabitants of the island actually did a good job of being friendly to their environment, it was more so the

europeans that led to its destruction.

- Overall lesson: People need to care and learn to live within their means.

CASE STUDY: Black and White, and Spread all Over: Zebra Mussels Invade the Great Lakes (pgs 73-74)

-Invasive species that spread to all 5 great lakes

-Clog pipes, eat phytoplankton which decreases their population who are the foundation of the great lakes ecosystem

CASE STUDY: How Do Zebra Mussels Affect Fish Communities? (pgs 84-85)

-Mussels declined phytoplankton, zooplankton, and invertebrate animal populations

-Bottom dweller populations rose

a. Mussels provided shelter and nutrients for bottom dwellers

-Caused fish to shift up or down stream

a. Littoral-feeding fish shifted towards the mussels

a. Open water fish shifted away from mussels

CASE STUDY: The Vanishing Oysters of the Chesapeake Bay (pgs 103-104)

Demise of the island came when the Chesapeake Bay depleted oyster fisheries from over-harvesting, now EPA protecting the restoration of oysters

CASE STUDY: Will we slice through the Serengeti? (pgs 269-270)

-Buffalo migration could be stopped if there is a highway built through the Serengeti

-Want the highway to make trade better but has negative environmental implications

CASE STUDY: Why is Wildlife Declining in African Reserves? (pgs 280-281)

-Animal populations are declining inside and outside of reserves in Africa

-Due to increased settlements, destruction of habitats, local residents killing local wildlife, and livestock competing with wild animals for grassland foods

CASE STUDY: Alberta's Oil Sands and the Keystone XL Pipeline (515-516)

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CASE STUDY: Fracking the Marcellus Shale (pgs 159-160)

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CASE STUDY: Does Fracking Contaminate Drinking Water? (pgs 164-165)

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CASE STUDY: How do Climate Models Work? (pgs. 490-491)

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CASE STUDY: Rising Seas Threaten South Florida (479-480)

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CASE STUDY: Germany Goes Solar (pgs. 577-578)

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CASE STUDY: Mining for... Cell Phones? (pgs 629-630)

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environmental science

systematic study of our environment and our place in it

Environment

circumstances or conditions that surround an organism

opinion

a personal belief or judgement

fact

readily observable evidence

bias

a particular tendency or inclination, especially one that prevents unprejudiced consideration of a question

science

a systematic process of learning about the world and testing out understanding of it

scientific method

a scientist makes an observation and asks questions of some phenomenon

theory

probable cause-and-effect relationships of the evidence that has been observed (evolution, climate change, relativity, the big bang)

law

indisputable principles that govern the universe (gravity, thermodynamics)

paradigm shift

a dramatic upheaval in thought that changes the dominant viewpoint

morals

an individual or society's distinction from right and wrong

ethics

a system of moral principles; criteria that help distinguish right from wrong

environmental ethics

the application of ethical standards to relationships between humans and nonhuman entities

ecological footprint

environmental impact of a person or population; the area of biologically productive land + water to supply raw resources & dispose/recycle waste

GDP

gross domestic product (how much we make)

GPI

genuine progress indicator (how happy we are)

Know the definitions, order, and steps in the scientific method

1. observation:

2. question:

3. hypothesis: a statement that tries to explain the question

4. predictions: specific statements that can be directly tested

5. test:

6. results: the test results either support or reject the hypothesis

What is "burden of evidence" as it relates to scientific advancement?

theories become validated as more and more evidence is gathered that supports the theory and

little evidence to contract the theory. Evidence that contradicts a well-established theory needs to be highly validated, and forms a paradigm shift.

• extraordinary claims require extraordinary evidence

Four major environmental management strategies we have employed in the past and today. How are they similar or different?

1. Domination of Nature: control nature to improve the human condition (early European Americans); nature needs to be

tamed and exists solely for our benefit.

• typically leads to deforestation, over-hunting, over-fishing, and resource depletion • tragedy of the commons

2. Altruistic Preservation: preservation of wilderness (Emerson, Thoreau, Muir) • example: national parks

3. Resource (utilitarian) Conservation: use of resources for the greatest good of the largest number over the longest time (Pinchot, Roosevelt);

• Pinchot: managing forests to produce for the service of mankind

• multiple use management: efficiency, equity, and sustainability in use of natural resources; limited concern for

economics, sociology, future need

• maximum sustained yield; may result in tragedy of the commons

4. Ecological Management: preservation of the integrity, stability, and beauty of the biotic community (Leopold) • retain functioning natural systems; focus on species interactions & sustainability

Resource conservation

Conservation efforts in our forests mainly focus on creating a maximum sustained yield of a shared resource like lumber, soil, or peat moss.

What is the tragedy of the commons on a shared resource?

People/animals taking too much of a resource for themselves until the resource is depleted by overgrazing/ consumption

Are National Forests and National Parks conserved or preserved?

• National Forest Service: (conservation) managed by Dept. of Agriculture

• National Park System: (preservation) managed by Dept. of Interior

Determine whether a management approach is preservationist or conservationist

-Management approaches are conservationist because it still allows for humans to seek benefit

-US Forest Service

-Efficient, equitable, and sustainable use of natural resources

What are some key features of ecological management of natural areas?

Retain functioning natural systems

Focus on species interactions

Humans as part of ecosystem, not simply stewards

Thinking towards sustainability

What are ecological services and be able to provide five good examples for a given environment.

Pollination

Biological control

Erosion control

Water supply

Waste treatment

species

(biological species concept) a population or group of populations whose members share characteristics and can breed with one another to produce fertile offspring

population

a group of individuals of a species that live in the same area

evolution

genetic change in populations over time that lead to changes in appearances, functioning, or behavior over generations; may be random or generated by natural selection

natural selection

traits that enhance survival and reproduction are passed on more frequently to future generations than those that do not

adaption

the process where, over time, characteristics (traits) that lead to better reproductive success become more prevalent in the population

mutations

accidental changes in DNA that may be passed on to the next generation; non-lethal mutations provide the genetic variation on which natural selection acts. Almost all mutations are neutral or bad, few "good"

phenotype

visible, expressed traits

genotype

genetic makeup of an organism

niche

an organism's use of resources and functional role in the community (habitat use, food selection, role in energy and nutrient flow, interactions with other individuals)

specialists

species with narrow niches and specific needs; extremely good at what they do but are vulnerable to when their conditions change

generalists

-species with broad niches

-use a wide array of habitats and resources

-can live in many different places

allopatric speciation

species formation due to physical separation of populations; main mode of speciation; each population gets its own mutations, natural selection can speed the process

convergent evolution

unrelated species may acquire similar traits because they live in similar environments

coevolution

process in which two species evolve over time in response to each other; become locked in a duel of escalating adaptations (evolutionary arms race)

extinction

the disappearance of a species from earth

endemic species

Any species whose range is restricted to a limited geographical area!!! especially vulnerable to extinction (U.S. amphibians with small ranges; U.S. salamander species that live on the top of one mountain)

Be able to describe the four assumptions or criteria of Natural Selection. Four observations regarding genetic variation:

1. Overproduction: each species produces more offspring than what will survive to maturity

2. Variation: individuals in a population exhibit genetic variation

3. Limits on Population Growth: resource limitations will keep populations in check

4. Differential Reproductive Success: individuals with the most favorable traits are more likely to reproduce; results in competitive advantage

Which competition is more aggressive, intraspecific or interspecific? And why?

• intraspecific: competition between individuals in a population

• interspecific: competition between individuals in two different species (more aggressive)

What is competitive exclusion and please provide an example

competitive exclusion: one species excludes the other from using a competitive resource (zebra mussels in the

Great Lakes)

What is the concept of species coexistence and please provide an example

• species coexistence: coexisting species' niche differ from each other in some way (example of natural selection; many different populations in one pond using species-specific resources)

What is artificial selection and how does it differ from natural selection? Provide examples

• natural selection: traits that enhance survival and reproduction are passed on more frequently to future generations

than those that do not (Hawaiian Honeycreeper's long beak)

• artificial selection: the process of genetic selection under human direction (dog breeding)

What is the Anthropocene and how is it different from any other time in Earth's history?

-The proposed new epoch where humans are profoundly affecting extinction rates in a very negative way

-There have been 5 mass extinction in the earth's history→ loosing 50-95% of species each time

-This is the first-time extinction is because of humans

Why would a species endemic to a single mountain range be more at risk of extinction than an organism that is a generalist and can live many different places?

-If you can live in more climates, you are better able to adapt to changes in the environment

-More genetic diversity

What are K-selected species and r-selected species? How do they differ?

K = carrying capacity

K-selected: produce fewer young, reproduce later in life, parental care over young, the young are density dependent, very small but competitive species

R-selected: produce many young, little or no parental care, young are density independent, mature reproduce and die quickly

How can you tell if a species is density dependent or independent?

density dependent species have directly related mortality and population density rates

• density independent species' natality and mortality rates are unaffected by population density

Describe the four factors that contribute to population change.

1. Natality: births within a population

2. Mortality: deaths within a population

3. Immigration: arrival of individuals outside of the population 4. Emigration: departure of individuals from the population

Why do some species experience exponential growth? What types of species undergo this type of growth?

• Exponential growth occurs in nature with small populations, low competition, and/or ideal conditions.

What is carrying capacity and how is that influenced by limiting factors?

• carrying capacity: the maximum population size of a species that its environment can sustain

• limiting factors slow and stop exponential growth; many factors contribute to environmental resistance and

influence a population's growth rate and carrying capacity

What are some common limiting factors to populations?

• limited water, limited space, limited food, predators, disease, etc.

ecology

the study of the relationships between organisms and their environment, both living and non-living

trophic levels

links in a food chain through which energy from food passes down from one organism to another

keystone species

A species that has strong or wide-reaching impact far out of proportion to its abundance. It is vital to an ecological community and a removal of a keystone species could have major consequences

carrying capacity

the largest population that an environment can support at any given time

limiting factor

An environmental factor that prevents a population from increasing

logistic growth curve vs exponential growth curve

-logistic growth curve: S-shaped curve, population expansion decreases as resources become scarce. increase gradually at first, more rapidly in the middle growth period, and slowly at the end, leveling off at a maximum value after some period of time. (at K= carrying capacity)

-exponential growth curve: When resources are unlimited, populations exhibit exponential growth, resulting in a J-shaped curve.

Compare and contrast food chains and food webs; which is a more accurate representation of the natural world?

• food chains: energy from food passes from one organism to the other

• food webs: a visual map of energy flow that uses arrows to show the many paths along which energy passes as

organisms consume one another (more accurate representation)

Why are there only 3° or 4° consumers in a typical food chain?

there is limited energy available within the food chain; each consumer has fewer predators coming after it than the last, the energy gets transferred between tropic levels

How much energy is typically transferred between tropic levels? Where does the other energy go?

Only about 10% of the energy of the prey is passed between tropic levels

The rest of the energy is lost through the metabolic process as heat

What does the concept, "energy flows, matter cycles" mean?

• energy flows through the ecosystem as chemical energy is transferred from each preceding organism and heat is released as a byproduct. (the heat lost from each consumer is replaced by the sun's heat used by the producers)

• matter is conserved and cycled within the ecosystem as nutrients is transferred from each preceding organism.

What would happen to matter if detritivores and decomposers were absent in a community?

detritivores and decomposers use the chemical energy and nutrients from the producers and consumers to make detritus (non-living organic matter) to fuel the ecosystem.

How do humans create algal blooms, which lead to dead zones, or anoxic/eutrophic conditions?

Algal blooms are created when we add extra nutrients to a body of water (nitrogen, phosphorus, etc.)→ blooms of algae, increased production of organic matter that dies and sinks, decomposition and loss of dissolved oxygen→ dead zones

How common are harmful algal blooms (HAB) and what do they do?

-Reasonably common and they cause the water to be bad and wildlife die because there is not enough oxygen

-In rarer cases some phytoplankton produce HABs and toxins which is unsafe for humans

What is the Dead Zone in the Gulf of Mexico and what human activity causes this phenomenon?

• 5-7k square miles in the Gulf of Mexico

• formed predominantly from agriculture runoff from the Mississippi River Basin

• caused by excess nutrients and warming water, suffocating marine life as the level of dissolved oxygen in the water

becomes too low

What are three ways Zebra and Quagga mussels have impacted industry and biodiversity in North America, especially the United States?

1. Clog pipes which leads to property damage

2. Killed other species?

3. Forced fish to move up and downstream?

Know the difference between positive and negative feedback loops. Which are more common in nature? Which are more commonly created by human activities?

Positive feedback loop: RARE IN NATURE → HUMANS: system output causes the system to change in the same way and drives it further towards one extreme or another (exponential population growth, spread of cancer, melting sea ice)

Negative feedback loop: IN NATURE: the system changes and moves in one direction, which causes the system to correct itself and balance out by moving in the other direction (homeostasis) (exp. Body temperature)

inbreeding depression

genetically similar parents mate and produce inferior offspring

species richness

Species richness is simply a count of species, and it does not take into account the abundances of the species or their relative abundance distributions.

species diversity

Species diversity takes into account both species richness and species evenness.

latitudinal diversity gradient

observation that current areas at low latitude have higher number of species than higher latitude areas; more species near equator

endangered species

species that are considered to be in imminent danger of extinction

threatened species

species that are likely to become endangered, at least locally, within the foreseeable future

vulnerable species

species that are naturally rare or have been locally depleted by human activities to a level that puts them at risk

umbrella species

species selected for making conservation-related decisions, typically because protecting these species indirectly protects the many other species that make up the ecological community of its habitat.; if you protect this species, many other species will also be protected.

conservation biology

the study of the factors behind the loss, protection, and restoration of biodiversity

biodiversity hotspots

Relatively small areas of land that contain an exceptional number of endemic species and are at high risk from human activities

Why would populations with high genetic diversity be more resilient to environmental change or disease? Why would populations with low genetic diversity be more vulnerable?

-With low genetic diversity, the two parents have more similar genes and produce inferior offspring, more vulnerable to environmental change or disease

-With high genetic diversity populations are more resilient

Why would more species in an area with more interspecies interactions create more ecosystem resilience? (Think about niches and ecosystem services)

-More genetic diversity→ if one species goes away there are other food sources;

• when the richness and evenness (relative abundance) are higher in an ecosystem allow adaptation to alternative resources when the ecosystem changes. For example, a species that relies entirely on one resource for food will suffer immensely when their food source is no longer accessible (polar bears and hunting seals off of diminishing sea ice)

What causes inbreeding depression?

• populations have low genetic diversity

What is the major cause of extinction or loss of biodiversity?

habitat loss

Why are species more abundant at the equator?

• latitudinal gradient: species richness increases toward the equator (due to temperate climate throughout the year- stable climate, more coastal areas)

Again, know at least five ecosystem services.

-provides food, fuel, fiber, and shelter

-purifies air and water & detoxifies waste

-stabilizes climate, moderates floods, droughts, wind, and temperature

-cycles nutrients, renews soil fertility

-pollinates plants and controls pests and disease

-maintains genetic resources, allowing species to adapt to change

-provides cultural and aesthetic benefits

How does biodiversity impact tourism, in particular ecotourism? How could these activities boost conservation efforts? Could they also have a negative impact on a particular region?

Biodiversity boosts economies with ecotourism

People want to protect things that are linked to tourism, but over harvesting and other things that could be used for tourism can harm the environment