Ap/ib Bio Chapter 53

Front 1

species richness

Back 1

The number of species in a biological community.

Front 2

relative abundance

Back 2

Differences in the abundance of different species within a community.

Front 3

species diversity

Back 3

The number and relative abundance of species in a biological community.

Front 4

Predation

Back 4

An interaction between species in which one species, the predator, eats the other, the prey.

Front 5

individualistic hypothesis

Back 5

The concept, put forth by H. A. Gleason, that a plant community is a chance assemblage of species found in the same area simply because they happen to have similar abiotic requirements.

Front 6

interactive hypothesis

Back 6

The concept, put forth by F.E. Clements, that a community is an assemblage of closely linked species, locked into association by mandatory biotic interactions that cause the community to function as an integrated unit, a sort of superorganism.

Front 7

secondary succession

Back 7

A type of succession that occurs where an existing community has been cleared by some disturbance that leaves the soil intact.

Front 8

interspecific interactions

Back 8

Relationships between species of a community.

Front 9

Coevolution

Back 9

The mutual evolutionary influence between two different species interacting with each other and reciprocally influencing each other’s adaptations.

Front 10

Parasitism

Back 10

A symbiotic relationship in which the symbiont (parasite) benefits at the expense of the host by living either within the host (as an en-doparasite) or outside the host (as an ectoparasite).

Front 11

Parasitoidism

Back 11

A type of parasitism in which an insect lays eggs on or in a living host; the larvae then feed on the body of the host, eventually killing it.

Front 12

Herbivory

Back 12

An interaction in which an herbivore eats parts of a plant or alga.

Front 13

Community

Back 13

All the organisms that inhabit a particular area; an assemblage of populations of different species living close enough together for potential interaction.

Front 14

Biogeography

Back 14

The study of the past and present distribution of species.

Front 15

cryptic coloration

Back 15

Camouflage, making potential prey difficult to spot against its background.

Front 16

aposematic coloration

Back 16

The bright coloration of animals with effective physical or chemical defenses that acts as a warning to predators.

Front 17

Mimicry

Back 17

A phenomenon in which one species benefits by a superficial resemblance to an unrelated species. A predator or species of prey may gain a significant advantage through mimicry.

Front 18

Predator

Back 18

An organism that eats other living organisms.

Front 19

Batesian mimicry

Back 19

A type of mimicry in which a harmless species looks like a species that is poisonous or otherwise harmful to predators.

Front 20

Mullerian mimicry

Back 20

A mutual mimicry by two unpalatable species.

Front 21

Parasite

Back 21

An organism that benefits by living in or on another organism at the expense of the host.

Front 22

Hosts

Back 22

The larger participant in a symbiotic relationship, serving as home and feeding ground to the symbiont.

Front 23

Endoparasites

Back 23

A parasite that lives within a host.

Front 24

Ectoparasites

Back 24

A parasite that feeds on the external surface of a host.

Front 25

interspecific competition

Back 25

Competition for resources between plants, between animals, or between decomposers when resources are in short supply.

Front 26

interference competition

Back 26

Competition in which one species activley interferes with the ability of another to use a resource

Front 27

exploitative competition

Back 27

Occurs indirectly through a common limiting resource which acts as an intermediate. For example the use of the resources depletes the amount available to others, or they compete for space.

Front 28

competitive exclusion principle

Back 28

The concept that when populations of two similar species compete for the same limited resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population.

Front 29

ecological niche

Back 29

The sum total of an organism's utilization of the biotic and abiotic resources of its environment.

Front 31

fundamental niche

Back 31

The place or function of a given organism within its ecosystem

Front 32

Prey

Back 32

An organism eaten by another organism

Front 33

realized niche

Back 33

The niche a viable population of a species occupies in the presence of competitor species

Front 34

resource partitioning

Back 34

The division of environmental resources by coexisting species populations such that the niche of each species differs by one or more significant factors from the niches of all coexisting species populations.

Front 35

character displacement

Back 35

The tendency for characteristics to be more divergent in sympatric populations of two species than in allopatric populations of the same two species.

Front 36

Symbiosis

Back 36

An ecological relationship between organisms of two different species that live together in direct contact.

Front 37

Symbiont

Back 37

The smaller participant in a symbiotic relationship, living in or on the host.

Front 38

Commensalism

Back 38

A symbiotic relationship in which one organism benefits but the other is neither helped nor harmed.

Front 39

Mutualism

Back 39

A symbiotic relationship in which both participants benefit.

Front 40

keystone species

Back 40

A species that is not necessarily abundant in a community yet exerts strong control on community structure by the nature of its ecological role or niche.

Front 41

exotic species

Front 42

Stability

Back 42

intermediate variants by acting against extreme phenotypes

Front 43

Disturbances

Back 43

A force that changes a biological community and usually removes organisms from it. Disturbances, such as fire and storms, play pivotal roles in structuring many biological communities.

Front 44

ecological succession

Back 44

Transition in the species composition of a biological community, often following ecological disturbance of the community; the establishment of a biological community in an area virtually barren of life.

Front 45

primary succession

Back 45

A type of ecological succession that occurs in a virtually lifeless area, where there were originally no organisms and where soil has not yet formed.

Front 46

Recruitment

Back 46

The process of progressively increasing the tension of a muscle by activating more and more of the motor neurons controlling the muscle.

Front 47

dynamic equilibrium hypothesis

Back 47

The idea that long food chains are less stable than short chains.

Front 48

intermediate disturbance hypothesis

Back 48

The concept that moderate levels of disturbance can foster greater species diversity than low or high levels of disturbance.