Chapter 53- Community Ecology

Question 1

Community

Answer 1

Consists of interacting species, usually living within a defined area.

Question 2

Fitness

Answer 2

The ability to survive and produce offspring.

Question 3

Competition

Answer 3

Occurs when individuals use the same resources, resulting in lower fitness for both.

Question 4

Consumption

Answer 4

Occurs when one organism eats or absorbs nutrients from another. The interaction increases the consumers fitness but decreases the victims fitness.

Question 5

Mutualism

Answer 5

Occurs when two species interact in a way that confers fitness benefits to both.

Question 6

Commensalism

Answer 6

Occurs when one species benefits but the other species is unaffected.

Question 7

Coevolutionary Arms Race

Answer 7

A repeating cycle of reciprocal adaptation.

Question 8

Intraspecific Competition

Answer 8

Competition for resources between members of the same species that intensifies as population density increases.

Question 9

Interspecific Competition

Answer 9

Occurs when individuals from different species use the same limiting resources.

Question 10

Niche

Answer 10

The range of resources that the species is able to use or the range of conditions it can tolerate.

Question 11

Competitive Exclusion

Answer 11

Hypothesis by G.F. Gause; States that it is not possible for species with the same niche to coexist.

Question 12

Asymmetric Competition

Answer 12

One species suffers a much greater fitness decline than the other species does.

Question 13

Symmetric Competition

Answer 13

Each of the interacting species experiences a roughly equal decease in fitness.

Question 14

Fundamental Niche

Answer 14

The combination of resources or areas used or conditions tolerated in the absence of competitors.

Question 15

Realized Niche

Answer 15

The portion of resources or areas used or conditions tolerated when competition occurs.

Question 16

Fitness Trade-offs

Answer 16

Inevitable compromises in adaptation.

Question 17

Niche Differentiation

Answer 17

Change in resource use between competing species as a result of character displacement.

Question 18

Character Displacement

Answer 18

Tendency of traits between similar species that occupy overlapping niches to change in order to reduce interspecific competition.

Question 19

Herbivory

Answer 19

When herbivores consume plant tissues.

Question 20

Herbivores

Answer 20

Plant-eaters

Question 21

Parasitism

Answer 21

Occurs when a parasite consumes relatively small amounts of tissue or nutrients from another individual, the host.

Question 22

Parasite

Answer 22

An organism that consumes tissue or nutrients from another organism.

Question 23

Host

Answer 23

The organism who is consumed by parasites.

Question 24

Predation

Answer 24

When a predator kills and consumes all or most of another individual.

Question 25

Standing/Constitutive Defenses

Answer 25

Traits that allow individuals to avoid being eaten.

Question 26

Mimicry

Answer 26

When one species closely resembles another species.

Question 27

Mullerian Mimicry

Answer 27

When harmful species resemble each other.

Question 28

Batesian Mimicry

Answer 28

When a harmless species resembles a harmful species, to avoid predators.

Question 29

Inducible Defenses

Answer 29

Defensive traits that are produced only in response to the presence of a predator.

Question 30

Meta-Analysis

Answer 30

A study of studies, meaning an analysis of a large number of data sets on a particular question.

Question 31

Integrated Pest Management

Answer 31

Strategies to maximize crop and forest productivity while using a minimum of insecticides or other types of potentially harmful compounds.

Question 32

Climax Community

Answer 32

A stable community that does not change over time.

Question 33

Plankton

Answer 33

Microscopic species that live near the surface of water and swim very little if at all.

Question 34

Keystone Species

Answer 34

A species that has a much greater impact on the distribution and abundance of the surrounding species than its abundance and total biomass would suggest.

Question 35

Disturbance

Answer 35

Any event that removes biomass from a community.

Question 36

Disturbance Regime

Answer 36

Characteristic disturbances experienced by communities; often predictable in frequency and severity.

Question 37

Succession

Answer 37

The recovery from a disturbance that removes all or most of the organisms from an area.

Question 38

Primary Succession

Answer 38

When a disturbance removes the soils and its organisms as well as organisms that live above the surface.

Question 39

Secondary Succession

Answer 39

When a disturbance removes some or all of the organisms from an area but leaves the soil intact.

Question 40

Pioneering Species

Answer 40

Tend to have weedy life histories.

Question 41

Weed

Answer 41

A plant that is adapted for growth in disturbed soils.

Question 42

Facilitation

Answer 42

Takes place when the presence of an early arriving species makes conditions more favorable for the arrival of certain later species, by providing shade or nutrients.

Question 43

Tolerance

Answer 43

Existing species do not affect the probability that subsequent species will become established.

Question 44

Inhibition

Answer 44

Occurs when the presence of one species inhibits the establishment of another.

Question 45

Species Richness

Answer 45

A simple count of how many species are present in a given community.

Question 46

Species diversity

Answer 46

A weighted measure that incorporates a species’ relative abundance as well as its presence or absence.

Question 47

Intermediate Disturbance Hypothesis

Answer 47

Holds that regions with a moderate type, frequency, or severity of disturbance should have high species richness and diversity.