Exam 2

Question 1

How does competition impact each species?

Answer 1

negative impact

Question 2

How do predation, parasitism, and herbivory impact each species?

Answer 2

negative impact on one, positive impact on the other

Question 3

How does mutualism impact each species?

Answer 3

benefits both

Question 4

What is competition typically over?

Answer 4

usually subtle, over food, water, space, shelter, mates, sunlight

Question 5

How do effective competitors treat others?

Answer 5

exclude entirely or coexist

Question 6

Resource partitioning

Answer 6

species adapting to feed on different versions of the same thing; using the same resource different ways

Question 7

What benefits predators better at catching prey over other predators?

Answer 7

longer lives, better reproduction, better providers for offspring

Question 8

Host

Answer 8

who parasites depend on and who may or may not die in the long run

Question 9

What are the most common herbivores?

Answer 9

insects

Question 10

How do plants ward off insects that feed on them?

Answer 10

produce chemicals, thorns, and attract insects that feed on harmful insects

Question 11

Mycorrhizae

Answer 11

symbiotic relationships between fungi and plants, in which plants provide energy and protection and fungi help absorb nutrients from the soil

Question 12

How do plants and pollinators benefit each other?

Answer 12

bees/birds/bats transfer pollen to ovaries that grow into fruits, consuming pollen or nectar as their reward

Question 13

Food chain

Answer 13

linear series of feeding relationships

Question 14

What do decomposers and detritivores do?

Answer 14

enhance top soil layers and recycle nutrients

Question 15

How does the energy of higher trophic levels relate to that of lower trophic levels?

Answer 15

higher have about 10% of those below

Question 16

How do numbers of organisms of higher trophic levels compare to those of lower trophic levels?

Answer 16

more organisms of higher trophic levels

Question 17

How are food webs helpful?

Answer 17

to predict population changes

Question 18

How do keystone species benefit populations?

Answer 18

balance them out, especially keystone species of higher trophic levels

Question 19

Which trophic levels are most abundant?

Answer 19

lower trophic levels

Question 20

When does primary succession happen in terrestrial sites?

Answer 20

bare rock/sand/sediment becomes exposed and the species that colonize the new substrate are pioneer species

Question 21

Which pioneers are best suited to bare rock?

Answer 21

lichens (mutualistic fungi and algae)

Question 22

How does secondary succession occur?

Answer 22

fire, followed by pioneer species, then pine forests, then hardwood forests (each outgrow the previous population)

Question 23

How long do climax communities stay in place?

Answer 23

until disturbances restart succession

Question 24

When do regime shifts/phase shifts happen?

Answer 24

due to loss of a keystone species, passage of crucial climactic threshold, invasion of a non-native species

Question 25

When do introduced species become invasive?

Answer 25

when they leave behind predators and compete (limiting factors that previously regulated their population growth are absent)

Question 26

How can invasive species be beneficial?

Answer 26

European honeybees help the economy and pollinate, some control pests

Question 27

How can non-native species be beneficial?

Answer 27

increase biodiversity, help restore places devastated by human impact, provide resources for other organisms

Question 28

What is the most effective way to prevent invasive species from taking over?

Answer 28

prevent their arrival

Question 29

What do restoration ecologists do?

Answer 29

research historical conditions and either restore functionality of a system or return communities to their pre-settlement conditions

Question 30

What does ecological restoration involve?

Answer 30

undoing human disturbance by reintroducing natural processes, removing invasive species, planting native ones, modifying landscapes to reduce erosion or influence water patterns

Question 31

How does climate change affect the focus of restoration?

Answer 31

more focus on restoring function than restoring previous states

Question 32

What are the determining factors of biomes?

Answer 32

temperature and precipitation

Question 33

How are aquatic systems characterized?

Answer 33

temperature, salinity, dissolved nutrients, wave action, currents, depth, light levels, and substrate type, like biomes

Question 34

Deciduous trees

Answer 34

lose leaves and remain dormant in winter

Question 35

Coniferous trees

Answer 35

grow tall in temperate rainforests, creating a shaded/damp interior

Question 36

What happens to temperate rainforests when when trees are cleared?

Answer 36

soil is susceptible to landslides/erosion

Question 37

What negatively impacts tropical dry forest?

Answer 37

conversion for agriculture, so heavy wet season rains lead to soil loss

Question 38

How much rain do deserts receive?

Answer 38

less than 25 cm of precipitation per year

Question 39

How are fires in the summer in Chaparral/'Mediterranean' regions helpful?

Answer 39

plants resist and can depend on the fire for germination of their seeds

Question 40

Which was the first nation to implement population control policies?

Answer 40

India, now nearly the most populous country

Question 41

How much does the global population grow per year right now?

Answer 41

over 80 million

Question 42

What and when was the peak growth rate of the human population?

Answer 42

2.1% in the 1960s

Question 43

What are the typical estimates for carrying capacity?

Answer 43

1-2 billion healthy or 33 billion impoverished

Question 44

What other factors negatively impact the environment?

Answer 44

unsustainable resource consumption or degradation of ecosystems by pollution

Question 45

What do demographers attempt to do?

Answer 45

predict population dynamics/environmental impacts

Question 46

What determines a population's environmental impact?

Answer 46

density, distribution, composition

Question 47

Where are humans most populous?

Answer 47

temperate, subtropical, and tropical climates

Question 48

What is today's global median age, and what is the projected median age for 2050?

Answer 48

31 today, 36 in 2050

Question 49

What causes infant mortality?

Answer 49

poor nutrition, disease, exposure to hostile environments, exposure to hostile elements (higher in pre-industrial countries)

Question 50

What decreases total fertility rate?

Answer 50

industrialization, improved women's rights, family planning, quality healthcare

Question 51

What was Europe's rate of natural increase in 2020?

Answer 51

-0.1%

Question 52

How has average life expectancy increased in the last 50 years?

Answer 52

46 to 73

Question 53

Frank Notestein

Answer 53

demographer who proposed the demographic transition, arguing that industrialization caused parents to invest in quality of life over family size

Question 54

Demographic fatigue

Answer 54

some nations cannot make the demographic transition due to large populations, which make it hard to educate and employ young people

Question 55

How many women worldwide age 15 to 49 reported using modern contraceptives in 2020?

Answer 55

55%

Question 56

How many children can a typical woman have in her reproductive window healthily?

Answer 56

25

Question 57

How is wealth distributed over the human population?

Answer 57

richest 1/5th have over eighty times the income of the poorest 1/5th and use 85% of the resources

Question 58

What impact does one American have as opposed to in China, India, and Afghanistan?

Answer 58

one American equals two Chinese, six Indians, or eleven Afghans

Question 59

When did humans pass the Earth's capacity to support us?

Answer 59

1971 (we are now 50% beyond the Earth's means)

Question 60

Subspecies

Answer 60

populations of a species that occur in different geographic areas and differ slightly

Question 61

How does habitat diversity contribute to species diversity?

Answer 61

flat areas have less biodiversity than structurally diverse areas like forests

Question 62

Which family has the most species?

Answer 62

insects

Question 63

Where is biodiversity greater?

Answer 63

near the equator, due to the solar energy, heat, and humidity

Question 64

What happens when human disturbance replaces regionally unique habitats with homogenized disturbed habitats?

Answer 64

specialist species and species that rely on large expanses of habitat disappear, so species diversity decreases

Question 65

Why are there so many species we haven't found?

Answer 65

tiny species are overlooked, some organisms thought to be the same species turn out to be different upon close observation, humans haven't explored some parts of Earth (like ocean depths)

Question 66

How has food variety for humans changed throughout history?

Answer 66

7000 plant species and thousands of animal species throughout history, 15 crop species and 8 livestock species today

Question 67

How much do pharmaceuticals from wild species (about half of pharmaceuticals) make per year?

Answer 67

$150 billion

Question 68

What is the global economic value of seventeen major ecosystem services?

Answer 68

$155 trillion per year

Question 69

Who is most vulnerable to human impact?

Answer 69

specialists who can only use specific resources, have trouble coping with change, reproduce slowly, and rely on mature/well-vegetated habitats

Question 70

Where has most biodiversity loss happened?

Answer 70

tropical regions, due to deforestation

Question 71

How many species that have ever existed are estimated extinct?

Answer 71

99%

Question 72

What is the background extinction rate for mammals/marine animals?

Answer 72

1 species per 1-10 million per year

Question 73

What is the current global extinction rate compared with the background extinction rate?

Answer 73

tens to hundreds of times greater

Question 74

How many assessed species were reported threatened with extinction on the Red List in 2020?

Answer 74

27% of 120,000

Question 75

What are the five primary causes of population decline/species extinction?

Answer 75

habitat loss, pollution, over harvesting, invasive species, climate change

Question 76

How many of the world's temperate forests/grasslands/shrublands had been converted for humans by 1950?

Answer 76

more than half

Question 77

How much of the original Great Plains prairie habitat remains?

Answer 77

less than 1%

Question 78

How much money does illegal global trade of wildlife make?

Answer 78

over $20 billion per year

Question 79

Which species are most vulnerable to poaching?

Answer 79

large, long-lived, slow to reproduce species

Question 80

How do conservation geneticists use the minimum viable population size?

Answer 80

to determine how vital it is to increase a population

Question 81

Endangered Species Act

Answer 81

prevents destruction and trade of endangered or threatened individuals

Question 82

How are endangered species cloned?

Answer 82

DNA is taken from the endangered species and inserted into an egg which is then implanted into a female of a similar species

Question 83

How much has the land coverage of biodiversity hotspots decreased?

Answer 83

originally covered 15.7%, now cover 2.3% (which are still home to half of plant species and 42% of terrestrial vertebrate species)

Question 84

How much of the world's land area is protected as national parks, state parks, provincial parks, wilderness areas, biosphere reserves?

Answer 84

nearly 15%

Question 85

What are some limitations to protected areas of land?

Answer 85

animals wander on and off national parks and shift toward the poles due to global warming

Question 86

What portion of protected areas are managed using community-based conservation?

Answer 86

one quarter