*Umich Environ 201- Benedict Midterm Lectures 1-3

opinion

a personal belief or judgement

environment

circumstances or conditions that surround an organism

Environmental Science

the systematic study of our environment and our place in it

fact

readily observable evidence

the relation between opinions and facts

facts inform opinions, opinions cannot change facts

bias

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

____ people may fail to truly consider all facts

biased

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

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

difference between a preservationist & conservationist management approach

preservation = preservation of wilderness (limited interaction!)

conservation = managing to produce for the service of humankind, could result in tragedy of commons

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

1. Retain functioning natural systems

2. Focus on species interactions

3. Humans as part of ecosystem, not simply stewards

4.Thinking towards sustainability

What are ecological services?

- provide five good examples for a given environment.

definition: the many benefits to humans provided by the natural/healthy environment:

1. air quality regulation

2. climate regulation

3. water regulation

4. photosynthesis

5. nutrient cycling

6. pollination

species

(biological species concept) a population or group of populations -- members share characteristics

--can breed & produce fertile offspring

population

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

evolution

change over time

-- biological evolution: genetic change in populations over time

-- genetic changes lead to changes in appearance, function or behavior over generations

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 & 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 2 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?

more aggressive --> interspecific competition (different species)

What is competitive exclusion? provide an example

competitive exclusion: one species excludes the other from using a competitive resource

- (zebra mussels in the

Great Lakes vs native fish)

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 (giraffe's necks & feeding on tall trees)

• 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→ losing 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 (humans, elephants)

R = colonizer

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

name the four factors that contribute to population change.

1. Natality: births

2. Mortality: deaths

3. Immigration: arrivals

Emigration: departures

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?

- water

- space

- food

- predators

- disease