Community Ecology

Question 1

competition that occurs between individuals of the same species

Answer 1

Intraspecific

Question 2

competition that occurs between individuals of different species

Answer 2

Interspecific

Question 3

organisms compete indirectly through the consumption of a limited resource with each obtaining as much as it can

Answer 3

Exploitation Competition

Question 4

individuals interact directly with one another by physical force or intimidation

Answer 4

Interference Competition

Question 5

when knapwood secretes into the surrounding soil root chemicals (allelochemicals) that kill the roots of native grass species

Answer 5

Allelopathy

Question 6

unique set of habitat resources a species requires as well as its effect on an ecological system

Answer 6

Niche

Question 7

two species with exactly the same requirements cannot live together in the same place and use the same resources

Answer 7

Competitive Exclusion Principle

Question 8

differentiation of niches, in both space and time, that enables similar species to coexist in a community

Answer 8

Resource Partitioning

Question 9

occurring in the same geographic area

Answer 9

Sympatric

Question 10

occurring in different geographic areas

Answer 10

Allopatric

Question 11

tendency for two species to diverge in morphology and thus resource use because of competition

Answer 11

Character Displacement

Question 12

typically nonlethal predation on plants

Answer 12

Herbivory

Question 13

death of prey

Answer 13

Predation

Question 14

typically nonlethal; adult parasites usually live on and produce for long periods in or on the living host

Answer 14

Parasitism

Question 15

warning colorations

Answer 15

Aposematic Defense

Question 16

the blending of an organism with the background of its habitat and is a common method of avoiding detection by predators

Answer 16

Camouflage

Question 17

the resemblance of a species to another species

Answer 17

Mimicry

Question 18

two or more toxic species converge to look the same, thus reinforcing the basic distasteful design

Answer 18

Mullerian Mimicry

Question 19

mimicry of an unpalatable species by a palatable one

Answer 19

Batesian Mimicry

Question 20

compounds that are not part of the primary metabolic pathway; chemicals that are bitter tasting or toxic

Answer 20

Secondary Metabolites

Question 21

the ability of plants to prevent herbivory via either chemical or mechanical defenses

Answer 21

Host Plant Resistance

Question 22

an organism that lives in, or, or with another organism, called the host, in order to obtain nutrients, grow, or multiply, often directly or indirectly harming the host

Answer 22

Parasite

Question 23

lack chlorophyll and are totally dependent on host plants for their water and nutrients

Answer 23

Holoparasites

Question 24

able to carry out photosynthesis, but depend on their hosts for water and mineral nutrients

Answer 24

Hemiparasites

Question 25

infect one species or just a few closely related species

Answer 25

Monophagous

Question 26

can infect many different host species

Answer 26

Polyphagous

Question 27

multiply within their hosts

Answer 27

Microparasites

Question 28

live in the host but release infective juvenile stages outside of the host's body

Answer 28

Macroparasites

Question 29

live outside of the host's body

Answer 29

Ectoparasites

Question 30

live inside of the host's body

Answer 30

Endoparasites

Question 31

both species receive a benefit in the form of resource transfer of energy and nutrient

Answer 31

Resource-based Mutualisms

Question 32

one species receive food or shelter in return for defending another species

Answer 32

Defensive Mutualism

Question 33

interactions in which species receive food in return for transporting the pollen or seeds of its partner

Answer 33

Dispersive Mutualism

Question 34

when species cannot live without the other

Answer 34

Obligatory Mutualism

Question 35

interaction is beneficial but not essential to the survival and reproduction of either species

Answer 35

Facultative Mutualism

Question 36

interaction between species in which one benefits and the other is neither helped or harmed

Answer 36

Commensalism

Question 37

one organism uses a second organism for transportation

Answer 37

Phoresy

Question 38

factors that influence the number of different species in a community

Answer 38

Species Richness

Question 39

proposes that temperate regions have fewer species-rich communities than tropical ones because they are younger

Answer 39

Species-Time Hypothesis

Question 40

the observation that the number of species tends to increase with increasing area

Answer 40

Species-Area Effect

Question 41

proposes that greater production by plants results in greater overall species richness

Answer 41

Species-Productive Hypothesis

Question 42

the rate at which water moves into the atmosphere through the processes of evaporation from the soil and other surfaces and transpiration by plants, which are influenced by the amount of solar energy

Answer 42

Evapotranspiration rate

Question 43

frequency of occurrence

Answer 43

Relative Abundance

Question 44

a measure of the diversity of an ecological community that incorporates both the number of species and their relative abundance

Answer 44

Species Diversity

Question 45

converts values from species diversity indices into equivalent numbers of species.

Answer 45

Effective Number of Species

Question 46

outbreaks of pests are often found on cultivated land or land disturbed by humans, both of which are species-poor communities with few naturally occurring species

Answer 46

Diversity-Stability Hypothesis

Question 47

describes the gradual and continuous change in species composition of a community following a disturbance

Answer 47

Succession

Question 48

refers to succession on a newly exposed site that has no biological legacy in terms of plants, animals, or microbes, such as bare ground caused by a volcanic eruption or the sediment created by the retreat of glaciers

Answer 48

Primary Succession

Question 49

succession on a site that has previously supported life but has undergone a disturbance such as a fire, tornado, hurricane, or flood

Answer 49

Secondary Succession

Question 50

succession as proceeding through several stages to a distinct end point

Answer 50

Climax Community

Question 51

each colonizing species makes the local environment a little different, such as a little shadier or a little richer in soil nitrogen, so that it becomes more suitable for other species, which then invade and outcompete the earlier residents

Answer 51

Facilitation

Question 52

early colonists prevent colonization by other species

Answer 52

Inhibition

Question 53

any species can start the succession, but the eventual climax community is reached in a somewhat orderly fashion

Answer 53

Tolerance

Question 54

the number of species on an island tends toward an equilibrium number that is determined by the balance between two factors: immigration rates and extinction rates

Answer 54

Equilibrium Model of Island Biogeography

Question 55

suggests that species-rich communities are more stable than those with fewer species

Answer 55

Diversity-Stability Hypothesis

Question 56

ecosystem function increases rapidly at fairly low levels of species richness, but then levels off because most additional species are functionally redundant

Answer 56

Redundancy Hypothesis

Question 57

proposes that ecosystem function rises dramatically as species richness approaches its natural level

Answer 57

Keystone Hypothesis

Question 58

suggests that although ecosystem function can change as the number of species increases or decreases, the amount and direction of change are unpredictable

Answer 58

Idiosyncratic Hypothesis