Chapter 4 - Species Interactions and Community Ecology

Question 1

phytoplankton

Answer 1

microscopic photosynthetic algae, pratists, and cyanobacteria that drift near the surface of water bodies and generally form the first trophic level in an aquatic food chain.

Question 2

zooplankton

Answer 2

tiny aquatic animals that feed on phytoplankton and generally make up the second layer of the food chain

Question 3

competition

Answer 3

a relationship in which multiple organisms seek the same limited recourse

Question 4

intraspecific competition

Answer 4

competition that takes place among members of the same species

Question 5

interspecific competition

Answer 5

competition that takes place among members of two or more different species

Question 6

fundamental niche

Answer 6

the full niche of a species

Question 7

realized niche

Answer 7

the portion of the fundamental niche that is fully realized (used) by a species

Question 8

species coexistence

Answer 8

an outcome of intraspecific competition in which no competing species fully excludes the other and the species continue to coexist

Question 9

competition exclusion

Answer 9

an outcome of interspecific competition competition in which one species excludes another species from a resource entirely

Question 10

character displacement

Answer 10

a phenomenon resulting from competition among species in which competing species evolve characteristics that better adapt them to specifically use the portion of the resource that they use. the species essentially become more different from each other reducing their competition

Question 11

resource partitioning

Answer 11

the process by which species adapt to competition by evolving to use slightly different resources, or to use their shared resources in different ways, thus minimizing competition with one another

Question 12

predation

Answer 12

the process in which one species (the predator) hunts, tracks, captures, and eventually kills its prey

Question 13

predator

Answer 13

an organism that hunts, capture, kills and consumes individuals of another species, the prey

Question 14

prey

Answer 14

an organism that is killed and consumed by another species

Question 15

paratism

Answer 15

a relationship in which one organism, the parasite, depends on another, the host, for nourishment or some other benefit while simultaneously doing the host harm

Question 16

parasite

Answer 16

the organism in a parasitic relation ship that extracts nourishment or some other benefit from the host

Question 17

host

Answer 17

the organism in a parasitic relationship that suffers harm while providing the parasite nourishment or some other benefit

Question 18

parasitoid

Answer 18

an insect that parasitizes other insects, generally causing eventual death of the host

Question 19

pathogens

Answer 19

a parasite that causes disease in its host

Question 20

coevolution

Answer 20

the process in which two or more species evolve in response to each other. parasites and hosts may coevolve , as may flowering plants and their pollinators

Question 21

herbivory

Answer 21

the consumption of plants by animals

Question 22

pollination

Answer 22

a plant-animal interaction in which one organism (for example a bee or hummingbird) transfers pollen (containing male sex cells) from flower to flower, fertilizing ovaries that grow into fruits with seeds

Question 23

trophic levels

Answer 23

ranking in the feeding hierarchy of a food chain. organisms that have higher trophic levels consume those at lower trophic levels

Question 24

mutualism

Answer 24

a relationship in which all participating organisms benefit from their interactions

Question 25

symiosis

Answer 25

a relationship between different species of organisms that live in close physical proximities. people most often use this term to reference mutualistic relationships, but it can be used for both parasitic and mutualistic relationships

Question 26

tertiary consumer

Answer 26

an organism that consumes secondary consumers and feeds at the fourth trophic level

Question 27

carnivore

Answer 27

an organism that consumes animals

Question 28

detritivore

Answer 28

an organism such as a fungus or bacterium, that breaks down leaf litter and other non-living matter into simple constituents that can be taken up and used by plants

Question 29

food chain

Answer 29

a linear series of feeding relationships as organisms feed on one another, energy is transferred from lower to higher trophic levels

Question 30

food web

Answer 30

a visual representation of feeding interactions within an ecological community that shows an array of relationships between organisms of different trophic levels

Question 31

keystone species

Answer 31

a species that has an especially far reaching effect on a community

Question 32

trophic cascade

Answer 32

a series of changes in the population sizes of organisms at different trophic levels in a food chain, alluring when predators at higher trophic levels indirectly promote populations of organisms at low trophic levels in check. trophic cascades may be evident when a top predator is eliminated from a system

Question 33

disturbance

Answer 33

an event that affects environmental conditions rapidly and drastically, resulting in changes to the community and ecosystem. disturbance can be natural, or it van be caused by humans

Question 34

succession

Answer 34

a stereotypical series of changes in the structure of an ecological community through time

Question 35

primary succession

Answer 35

a stereotypical series of changes as an ecological community develops overtime, beginning with a lifeless substrate in terrestrial systems, primary succession begins when a piece of rock, sand, or sediment becomes newly exposed to the atmosphere and pioneer species arrive. when soil is lost

Question 36

secondary succession

Answer 36

a stereotypical series of changes as an ecological community develops overtime, beginning when some event disrupts or dramatically alters an existing community

Question 37

resistance

Answer 37

the ability of an ecological community to remain stable in the presence of a disturbance

Question 38

resilience

Answer 38

the ability of an ecological community to change in response to disturbance but later return to its original state.

Question 39

pioneer species

Answer 39

a species that arrives earliest, beginning the ecological process of succession in a terrestrial of aquatic community

Question 40

phase shift (regime shift)

Answer 40

a fundamental shift in the overall character of an ecological community generally occurring after some extreme disturbance and after which the community may not return to its original state

Question 41

no-analog community (novel community)

Answer 41

an ecological community composed of a novel mixture of organisms, with no current analog or historical precedent

Question 42

introduced species

Answer 42

species introduced by humans from one place to another (whether intentionally or not), a minority of introduced species become invasive species

Question 43

invasive species

Answer 43

a species that spreads widely and rapidly becomes dominant in a community, interfering with the communities normal functions

Question 44

climax community

Answer 44

in the traditional view of ecological succession, a community that remains in place with little modification (until a disturbance comes along)

Question 45

restoration ecology

Answer 45

the study of the historical conditions of ecological communities as they existed before humans altered them. principles of restoration ecology are applied to the practice of ecological restoration

Question 46

ecological restoration

Answer 46

efforts to reverse the effects of human disruption of ecological systems and to restore communities to their conditions before disruption

Question 47

biome

Answer 47

a major regional complex of similar plant communities; a large ecological unit defined by its dominant plant type and vegetation structure

Question 48

climate diagram (climograph)

Answer 48

a visual representation of a regions average monthly temperature and precipitation

Question 49

temperate deciduous forest

Answer 49

a biome consisting of midlatitude forests characterized by broad-leafed trees that lose their leaves each fall and remain dormant during the winter. these forests occur in areas where precipitation is spread relatively evenly throughout the year; much of Europe, eastern china, and eastern north america

Question 50

temperate grassland

Answer 50

a biome whose vegetation is dominated by grasses and features more extreme temperature differences between winter and summer and less precipitation than temperate deciduous forests. also known as steppe, prairie

Question 51

forest

Answer 51

any ecosystem characterized by having a high density of tress

Question 52

tropical dry forest

Answer 52

a biome that consists of deciduous trees and occurs at tropical and subtropical latitudes where wet and dry seasons each span about half a year. widespread in India, Africa, south america, and Northern Australia. also known as a tropical deciduous forest

Question 53

tropical rainforest

Answer 53

a biome that consists of year-round rain and uniformly warm temperatures. found in central america, south america, southwest Asia, west Africa, and other tropical regions

Question 54

temperate rainforest

Answer 54

a biome consisting of tall coniferous trees, cooler and less species full than tropical rainforests and milder and wetter than temperate deciduous forests.

Question 55

savanna

Answer 55

a biome characterized by grasslands interspersed with clusters of acacias and other trees. savanna is found across parts of Africa (where it was the ancestral home of our species), south america, Australia, india, and other dry tropical regions

Question 56

desert

Answer 56

the driest biome on earth, with annual precipitation of less than 25 cm, because deserts have relatively little vegetation to insulate them from temperature extremes, sunlight readily heats them in the daytime, but day time heat losses quality in the night, so temperatures vary widely from day to night and in different seasons

Question 57

tundra

Answer 57

a biome that is nearly as dry as a desert but is located at very high altitudes along the northern edges of Russia, Canada, and Scandinavia

Question 58

permafrost

Answer 58

in tundra, underground soil that remains more or less permanently frozen

Question 59

boreal forest

Answer 59

a biome of Northern coniferous forest that stretches in a broad band across much of Canada, Russia, Alaska, and Scandinavia, also known as taiga, boreal forest consists of a limited number of species of evergreen trees, such as black spruce, that dominate large regions of forest interspersed with occasional bags and lakes

Question 60

chaparral

Answer 60

a biome consisting mostly of densely thickened evergreen shrubs occurring in limited small patches. its “Mediterranean” climate of mild, wet winters and warm, dry summers is induced by oceanic influences. in addition to ringing the Mediterranean sea, chaparral occurs along the coast of California, Chile, and Southern Australia

Question 61

rain-shadow

Answer 61

a region of one side of a mountain range that experiences arid climate. this occurs because mountain moist air rising over the terrain from the opposite direction releases precipitation on the windward slope as it cools, leaving the airs humidity low, it descends over the peak and into the rain-shadow region