Test 2 Vocab

Front 1

Geometric Growth

Back 1

J-shaped graph

A result of unlimited population growth

p. 190

Front 2

Intrinsic rate of increase

Back 2

"r" is at its maximum rate when conditions are optimal for the population

r- per capita rate of increase

r decreases as generation time increases

Front 3

Exponential growth

Back 3

Results in a characteristic J-shaped curve

rate of increase is slightly greater for exponential growth than geometric growth

p. 194

Front 4

Carrying capacity (K)

Back 4

The upper boundary for the population size

(Logistic growth results in an upper limit to population size)

Front 5

Logistic Equation

Back 5

=rN((K-N)/K)

N= population size

discovered by Belgian mathematician P. F. Verhulst in 1838

Front 6

Time Lag

Back 6

a delay in response to change

p. 200

Front 7

Density-dependent factor

Back 7

a factor whose influence varies with the density of the population

affects higher proportion of individuals when pop. densities are higher...

examples p. 202

Front 8

Density-independent factor

Back 8

mortality factor whose influence is not affected by changes in population size or density

physical factors such as weather, drought, freezes, floods & fires ---> may also act as dependent factors

p. 204

Front 9

Inverse density-dependent factor

Back 9

a source of mortality that decreases with increasing population size

ex: lions eating same amount of wildebeest regardless of wildebeest density

Front 10

Life history strategies

Back 10

sets of physiological and behavioral features that incorporate not only reproductive traits but also survivorship and length-of-life characteristics, preferred habitat type and competitive ability

Front 11

Semelparity

Back 11

where all offspring are produced in a single reproductive event

Front 12

Iteroparity

Back 12

pattern of repeated reproduction at intervals throughout the life cycle

(common in most vertebrates & perennial plants)

Front 13

r-selected species

Back 13

high rate of per capita pop. growth (r) but poor competitive ability

Ex: A weed

Front 14

K-selected speices

Back 14

have more or less stable populations adapted to exist at or near carrying capacity

Ex: Oak tree

Front 15

Fecundity

Back 15

potential reproductive output

p. 208

Front 16

Demographic transition

Back 16

shift in birth and death rates

(3 stages) ---> 209

Front 17

Age structure

Back 17

relative numbers of individuals of each defined age class (commonly displayed as pop. pyramid)

Front 18

Fertility

Back 18

actual reproductive output of women

Front 19

Total fertility rates (TFR)

Back 19

the average number of live births a woman has during her lifetime if she were to live to the maximum age

Front 20

ecological Footprint

Back 20

the aggregate total of land needed for survival in a sustainable world

Front 21

Intraspecific

Back 21

competition between individuals of the same species

Front 22

interspecific

Back 22

competition between individuals of different species

Front 23

exploitation competition

Back 23

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

Front 24

interference competition

Back 24

individuals interact directly with one another by physical force or intimidation

Front 25

allelopathy

Back 25

asymmetric competition, where one species produces and secrets chemicals from its roots that inhibits the growth of another species

Front 26

apparent competition

Back 26

two species do not compete for the same resource but they do share at least one natural enemy

p. 223

Front 27

associational susceptibility

Back 27

occurs in plants where herbivores spill over from one species onto another

p. 223

Front 28

guid

Back 28

a group of species that feed on the same resource and in the same way

p. 227

Front 29

enemy release hypothesis

Back 29

suggests invasive are released from their natural enemies, which do not accompany them during invasions, and can devote more resources to growth and thus competition

...leading to the evolution of increased competitive ability

Front 30

superior competitor hypothesis

Back 30

suggests invasives are more efficient users of natural resources than natives

Front 31

propagule pressure hypothesis

Back 31

suggests invasives produce more progeny than some native species, and by sheer weight of numbers this permits them entry into natural communities and competitive superiority

Front 32

lack of environmental constraints hypothesis

Back 32

suggests preadaptation of some invaders to existing environmental conditions. With few limitations to many abiotic environments, these invaders can grow quickly and outcompete native species

Front 33

competitive exclusion principle

Back 33

By Garrett Hardin: complete competitors cannot coexist. Species may avoid competitive exclusion by partitioning resources or being of different sizes, which permits them to feed on different sized resources

Front 34

resource partitioning

Back 34

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

(also known as ghost of competition past)

p. 239

Front 35

proportional similarity analysis

Back 35

2nd approach to determine how much resource partitioning is necessary to permit coexistence:

a measure of how much overlap exists between species in their use of resources

Front 36

niche overlap

Back 36

the overlap in resource use by two or more species; sharing of niche space

Front 37

character displacement

Back 37

divergence in the characteristics of two otherwise similar species where their ranges overlap; caused by competition between the species in the area of overlap

Front 38

obligate mutualism

Back 38

neither species can live without the other

ex: lichens are inseparable of fungi and algae

Front 39

facultative mutualism

Back 39

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

Front 40

dispersive mutualism

Back 40

mutualism between plants and their pollinators or seed dispersers

Front 41

defensive mutualism

Back 41

mutualism involving defense of one species by another

often an animal defending a plant or herbivore

Front 42

resource-based mutualism

Back 42

involves the increased acquisition of resources for both species

Front 43

pollination syndromes

Back 43

the pattern of co-evolved traits between particular types of flowers and their specific pollinators

ex: flowers pollinated by hummingbirds have bright colors to attract the bird but little order b/c birds cant smell

Front 44

competition avoidance hypothesis

Back 44

the idea that seed dispersal is advantageous to plants because competition between seedlings and parent plants is avoided

Front 45

predator escape hypothesis

Back 45

the idea that seed dispersal is advantageous to plants because seedlings escape the seed predators that tend to congregate under the parent tree

Front 46

colonization hypothesis

Back 46

the idea that seed dispersal is advantageous to plants because parental locations are not always ideal for seed germination

Front 47

directed dispersal hypothesis

Back 47

the idea that seed dispersal is advantageous to plants because dispersers are likely to distribute seeds into optimal sites

Front 48

endosymbiosis

Back 48

a close association where one organism lives inside the body of another

ex: parasites, fungi in grasses, etc.

Front 49

endosymbiosis theory

Back 49

mitochondria of eukaryotes evolved from aerobic bacteria and that chloroplasts evolved from cyanobacteria, and both took up residence within a primordial eukaryotic cell

Front 50

inquilinism

Back 50

when one species used a second species for housing

ex: orchids grow in forks of tropical trees

Front 51

epiphytes

Back 51

plants which use other plants for support but gain water and nutrients from moist air or from runoff

Front 52

phoresy

Back 52

when one organism uses a second organism for transportation

ex: flower mites travel from flowers in the noses of hummingbirds

Front 53

metabiosis

Back 53

organism uses something produced by the first, usually after its death

ex: hermit crabs use snail shells for protection

Front 54

associational resistance

Back 54

the protection of one species by its close association with unpalatable neighbors

Front 55

aposematic coloration

Back 55

"warning coloration"

advertises an organisms unplatable taste

ex: ladybird beetles and tropical frogs

Front 56

cryptic coloration

Back 56

"camouflage"

the blending of an organism with the background of its habitat

ex: grasshoppers

Front 57

mimicry

Back 57

the resemblance of a species to another species

to secure protection fro predators

Front 58

batesian mimicry

Back 58

mimicry of an unplatable species by a palatable species

ex: fly with yellow and black stripes to look like bee but themselves are harmless

Front 59

mullerian mimicry

Back 59

noxious species converging to look the same to reinforce predator avoidance

Front 60

predator satiation

Back 60

the synchronous production of many progeny by all individuals in a population to satiate predators

ex: cicadas only coming out every 13 to 17 yrs

Front 61

aggressive mimicry

Back 61

predators mimic a harmless model, allowing them to get close to prey

ex: crab spiders look like flowers and sit in the center waiting to capture a pollinator

Front 62

maximum sustainable yield

Back 62

the largest number of individuals that can be removed without causing long-term changes in the population

Front 63

constitutive defenses

Back 63

plant defenses that are always present

Front 64

induced defenses

Back 64

plant defenses that are only switched on following herbivore attack

Front 65

secondary metabolites

Back 65

chemicals that are produced by plants that are not essential for cell function but are useful deterrents against herbivores

Front 66

quantitative defenses

Back 66

substances that are ingested in large amounts by the herbivore as it eats and that prevent energy gain from the digestion of food

(tested with caterpillars & oaks)

Front 67

qualitative defenses

Back 67

toxic substances that are effective in very small doses

Front 68

apparent plants

Back 68

long-lived, large and easy for herbivores to find

their defenses are usually quantitative effective against monophagous & polyphagous herbivores

Front 69

unapparent plants

Back 69

small, difficult to find, & unavailable to herbivores for long periods

defenses mainly qualitative

Front 70

carbon-nitrogen balance hypothesis

Back 70

explain how the types of defense produced are influenced by the environmental conditions

Front 71

optimal defense hypothesis

Back 71

suggests certain plants parts, such as flowers and seeds, are not so easily replaced as others such as leaves and twigs

such parts contain a higher proportion of plants defenses

Front 72

semiochemicals

Back 72

behavior-altering chemical messengers

Front 73

pheromones

Back 73

chemicals that act as sex attractants between males and females

Front 74

allelochemicals

Back 74

a substance produced by one organism that affects the growth and behavior of another species

Front 75

nitrogen limitation hypothesis

Back 75

the idea that organisms select their food based on its nitrogen content

Front 76

plant vigor hypothesis

Back 76

the idea that herbivores select the fastest growing plant parts because their richest in nitrogen

Front 77

plant stress hypothesis

Back 77

the idea that plant stressors, such as drought, tend to increase the susceptibility of plants to herbivores

Front 78

microparasites

Back 78

parasites that cause diseases

Front 79

parasitoids

Back 79

a specialized insect parasite that is usually fatal to its host and therefore might be considered a predator rather than a classical parasite

Front 80

ectoparasites

Back 80

parasites that live on the outside of the hosts body

Front 81

endoparasites

Back 81

parasites that live inside the hosts body

Front 82

holoparasites

Back 82

a parasitic plant that is wholly dependent on its host

ex: rafflesia

Front 83

hemiparasites

Back 83

a parasitic plant that is partly dependent on its host

ex: mistletoe and water

Front 84

definitive host

Back 84

the host in which macroparasites exhibit sexual reproduction

Front 85

intermediate host

Back 85

one or more species of host in which macroparasites develop but do not undergo sexual reproduction

Front 86

macroparasites

Back 86

parasites that live inside the host but do not cause disease

Front 87

kleptoparasitism

Back 87

form of feeding where one animal takes food that another has caught

Front 88

mafia hypothesis

Back 88

the idea that parasitic birds, such as cockoos or cowbirds, destroy all the eggs in a nest if their own egg has been removed

Front 89

biological control

Back 89

use of natural enemies ( diseases, parasites, predators) to regulate populations of pest species

Front 90

trophic cascade

Back 90

that idea that in a food web, each trophic level strongly influences that one below it so that in the end, top predators influence the density of primary producers

p. 334

Front 91

green earth hypothesis

Back 91

the idea that since the earth appears green, herbivores must have little impact on plant abundance

Front 92

indirect effect

Back 92

an effect of one species on another that is mediated by a third species; for example spiders benefit plants by eating insect herbivores

Front 93

ecosystem exploitation hypothesis

Back 93

the idea that the strength of mortality factors in communities varies with plant productivity

Front 94

environmental stress hypothesis

Back 94

in stressful habitats, higher trophic levels have little effect b/c they are rare or absent, and plants are effected mainly by environmental stress

Front 95

key factor

Back 95

a mortality factor that mirrors most closely the overall population mortality

Front 96

compensatory mortality

Back 96

mortality that increases or decreases following changes in other mortality factors operation on a population

ex: hunting could act in a compensatory way

Front 97

additive mortality

Back 97

mortality that occurs in addition to other existing mortality

ex: hunting could act in an additive way

weather kills off deer but hunting ADDS to the mortality

Front 98

diversity indices

Back 98

a measure of the number of species in a area and the relative distribution of individuals among those species

Front 99

rank abundance diagrams

Back 99

graphical plots of numbers of individuals per species against rank of species commonness in the community

measure of biodiversity

Front 100

organismic model

Back 100

a view of the nature of a community that considers it to be a tightly knit, interdependent association of species in much the same way as an organism is an interdependent association of organs

Front 101

individualistic model

Back 101

a view of the nature of a community that considers it to be an assemblage of species coexisting primarily because of similarities in their physiological requirements and tolerances

Front 102

principles of species individuality

Back 102

a view of the nature of a community that regards species distribution according to physiological needs and that most communities therefore integrate continuously

Front 103

relative abundance

Back 103

the frequency of occurrence of species in a community

Front 104

effective number of species

Back 104

the conversion of a species diversity index to an equivalent number of species

Front 105

dominance preemption model

Back 105

the first species to invade the community preempts a large fraction of the available resources

Front 106

similarity indices

Back 106

indices that directly compare how many species are in common to two communities

Front 107

denodrogram

Back 107

tree diagram

a figure that clusters similar things (sites) together

Front 108

species-time hypothesis

Back 108

the idea that communities diversify with time so that older communities areas contain the highest number of species

Front 109

species-energy hypothesis

Back 109

the idea that communities diversify with energy so that communities rich in energy, from the sun and with abundant water, as in moist tropical forests, contain the highest number of species

Front 110

evapotranspiration

Back 110

the sum of the water lost from the land by evaporation and plant transpiration

Front 111

intermediate disturbance hypothesis

Back 111

the proposal that moderately disturbed communities are more diverse than undisturbed or highly disturbed communities

Front 112

megadiversity

Back 112

those countries with the greatest numbers of species; used in targeting areas for conservation

Front 113

endemic

Back 113

an organism that is native to a particular region

Front 114

biodiversity hot spots

Back 114

those areas with greatest number of endemic species

Front 115

biophilia

Back 115

the idea that humans have an innate love of life

Front 116

diversity-stability hypothesis

Back 116

Elton's idea that species-rich communities are more likely to be stable than species-poor communities

Front 117

rivet hypothesis

Back 117

the idea that not all species are vital to the functioning of ecosystems and that many species are not needed; in the same way the airworthiness of a plane depends on specific critical rivets

Front 118

redundancy hypothesis

Back 118

the idea that most species are not vital to the functioning of ecosystems; in the same way only a few people, the crew, are needed in the functioning of an airplane, the passengers are redundant

Front 119

keystone hypothesis

Back 119

the idea that most species are vital to the functioning of ecosystems and that function decreases immediately as species richness declines

Front 120

idiosyncratic hypothesis

Back 120

the idea that community function and species richness are not linked in a predictable way

Front 121

species complenentarity

Back 121

the idea that species are complementary in their use of resources in a community; some species tap into deep soil moisture while others use water near the soil surface

Front 122

sampling effect

Back 122

the idea that species-rich communities perform better than species-poor communities b/c they have a better chance of containing a "superspecies"

Front 123

resistance

Back 123

the size of a force needed to change community structure

Front 124

resilience

Back 124

the ability of the community to return to equilibrium following disturbance; usually measured by the speed of the return, or the degree of disturbance from which the community can recover

Front 125

biotic resistance hypothesis

Back 125

the idea that species-rich communities are more resistant to invasion that species-poor communities

Front 126

invasional meltdown

Back 126

the idea that invasion of a community by exotic species predisposes the community to further invasion by more exotic species

Front 127

evolution of increased competitive ability hypothesis

Back 127

the idea that loss of natural enemies allows invasive species to devote more resources to competition and less to defense