Ch. 54 pt. 2

Question 1

Dominant species

Answer 1

most abundant or have the highest biomass

Question 2

Invasive species

Answer 2

may become dominant because they lack natural predators or parasites

Question 3

Keystone species

Answer 3

exert strong control on a community by their ecological roles, or niches
not abundant
remove one species, whole thing falls apart

Question 4

Ecosystem engineers (foundation species)

Answer 4

cause physical changes in the environment that affect community structure
ex. beaver dams

Question 5

Bottom up model

Answer 5

unidirectional influence from lower to higher trophic levels
presence of mineral nutrients, controls plant numbers, control herbivore numbers, controls predator models

Question 6

Top down model (trophic cascade model)

Answer 6

control come from the trophic level above
predators limit herbivores, herbivores limit plants, and plants limit nutrient levels

Question 7

Mesopredator release

Answer 7

populations of medium sized predators rapidly increase in ecosystems after the removal of larger, top carnivore

Question 8

Biomanipulation

Answer 8

deliberate alteration of an ecosystem by adding or removing species, especially predators

Question 9

F.E. Clements argument

Answer 9

plant communities had only one state of equilibrium, a climax community, controlled by climate

Question 10

A.G. Tansley argument

Answer 10

variation in abiotic conditions created many possible stable communities within a region

Question 11

H.A. Gleason

Answer 11

viewed communities as chance assemblages of species with similar abiotic requirements

Question 12

Disturbance

Answer 12

an event that changes a community, removes organisms from it, and alters resource availability

Question 13

Nonequilibrium model

Answer 13

communities as constantly changing after disturbance

Question 14

High level of disturbance

Answer 14

result of frequent and intense disturbance
exclude slow growing species

Question 15

Low levels of disturbance

Answer 15

result from low frequency or low intensity of disturbance
dominant species exclude less competitive species

Question 16

Intermediate disturbance hypothesis

Answer 16

moderate levels of disturbance can foster greater diversity than either high or low levels of disturbance

Question 17

Ecological succession

Answer 17

the sequence of changes in community composition following a disturbance

Question 18

Primary succession

Answer 18

occurs where no soil exists when succession begins

Question 19

Early arriving species three processes

Answer 19

facilitate the appearance of the later species
inhibit the establishment of later species
no affect on the establishment of later species

Question 20

Pioneering plants

Answer 20

liverworts, mosses, fireweed, Dryas, and willows
facilitate later arrivals by increasing soil nitrogen content

Question 21

Succession is the result of?

Answer 21

changes induced by the vegetation itself

Question 22

Secondary succession

Answer 22

where soil remains after a disturbance
abandoned agricultural land may return to its original state

Question 23

Two biogeographic factors that affect the species diversity of biological communities

Answer 23

latitude and area

Question 24

Species richness

Answer 24

is especially great in the tropics and generally declines in a gradient toward the poles

Question 24

Two main climatic factors correlated with biodiversity in terrestrial communities

Answer 24

sunlight and precipitation

Question 25

Evapotranspiration

Answer 25

the evaporation of water from soil plus transpiration of water from plants

Question 26

Potential evapotranspiration

Answer 26

measure of potential water loss, assuming water is available

Question 27

Where are evapotranspiration and potential evapotranspiration the highest?

Answer 27

warm, wet conditions of the tropics

Question 28

Species-area curve

Answer 28

a larger geographic area has more species

Question 29

Who developed a method for predicting the species diversity on islands?

Answer 29

Robert MacArthur and E.O Wilson

Question 30

Island equilibrium model

Answer 30

a method for predicting the species diversity on islands

Question 31

Species richness on islands represents a balance between?

Answer 31

immigration of new species and extinction of established species

Question 32

Island size and distance from the mainland affect?

Answer 32

immigration and extinction

Question 33

Number of species on an island increase,
immigration?
extinction?

Answer 33

decreases
increases

Question 34

On a smaller island
number of species?
immigration?
extinction?

Answer 34

decreases
decreases
increases

Question 35

On a larger island
number of species?
immigration?
extinction?

Answer 35

increases
increases
decreases

Question 36

Islands closer to the mainland
immigration?
extinction?

Answer 36

increases
decreases

Question 37

Islands further from the mainland
immigration?
extinction?

Answer 37

decreases
increases

Question 38

Equilibrium

Answer 38

rate of immigration is equal to the rate of extinction

Question 39

Pathogens

Answer 39

disease-causing microorganisms, viruses, viroids, and prions

Question 40

What are coral reef communities being killed by?

Answer 40

white band disease

Question 41

Why are oak trees dying?

Answer 41

sudden oak death (SOD) caused by protist Phytophitora ramorum decreased abundance of at least five bird species

Question 42

What is the H1N1 virus?

Answer 42

swine flu