ch. 54 part 1

Question 1

community

Answer 1

assemblage of populations of various species living close enough for potential interaction

Question 2

interspecific interactions

Answer 2

relationships between species in a community

Question 3

ex. of interspecific interactions

Answer 3

• competition
• predation
• herbivory
• parasitism
• mutualism
• commensalism

Question 4

how can interspecific interactions be summarized

Answer 4

positive, negative, no effect

Question 5

competition

Answer 5

species compete for resource in short supply that limits survival and reproduction

Question 6

what can strong competition lead to

Answer 6

competitive exclusion

Question 7

competitive exclusion

Answer 7

local elimination of a competing species

Question 8

G.F. Gause

Answer 8

Russian ecologist that concluded that 2 species competing for the same limiting resources cannot coexist permanently in the same place

Question 9

ecological niche

Answer 9

sum of an organism’s use of biotic and abiotic resources - ecological role

Question 10

how can ecologically similar species coexist in a community

Answer 10

if there are one or more significant differences in their niches

Question 11

resource partitioning

Answer 11

differentiation of ecological niches, enabling similar species to coexist in a community

Question 12

temporal partitioning of common spiny and golden spiny mouse

Answer 12

• both normally nocturnal
• where they coexist, golden spiny becomes diurnal (active during day)

Question 13

fundamental niche

Answer 13

niche potentially occupied by that species

Question 14

realized niche

Answer 14

niche actually occupied by that spcies

Question 15

character displacement

Answer 15

tendency for characteristics to be more divergent in sympatric populations of 2 species than in allopatric populations of the same 2 species

Question 16

sympatric

Answer 16

occurring within the same geographical area - overlapping in distribution

Question 17

allopatric

Answer 17

occurring in separate non-overlapping geographical areas

Question 18

exploitation

Answer 18

any +/- interaction in which one species benefits by feeding on the other species

Question 19

exploitative interactions include:

Answer 19

1. predation
2. herbivory
3. parasitism

Question 20

predation

Answer 20

interaction in which one species (predator) kills and eats the other (prey)

Question 21

what do predators have adaptations for

Answer 21

finding, identifying, catching, and subduing prey

Question 22

what adaptations do prey have

Answer 22

to avoid being eaten - behavioral defenses

Question 23

aposematic coloration

Answer 23

bright warning coloring in animals w/ effective chemical defenses

Question 24

cryptic coloration

Answer 24

camouflage - makes prey difficult to spot

Question 25

Batesian mimicry

Answer 25

palatable/harmless species mimics and unpalatable or harmful model

Question 26

Mullein mimicry

Answer 26

2+ unpalatable species resemble each other

Question 27

what can mimicry do for predators

Answer 27

enable them to approach prey

Question 28

herbivory

Answer 28

interaction in which an herbivore eats parts of a plant or algae

Question 29

what are most herbivores

Answer 29

invertebrates

Question 30

specialized adaptations of herbivores

Answer 30

- specialized teeth and digestive systems

Question 31

plants defenses against herbivory

Answer 31

- toxic/distasteful chemicals - mechanical defenses (spines/thorns)

Question 32

parasitism

Answer 32

one organism (parasite) derives nourishment from another organism (host), which is harmed in process

Question 33

endoparasites

Answer 33

parasites that live within body of their host

Question 34

ectoparasites

Answer 34

parasites that live on the external surface of a host

Question 35

life cycle of many parasites can involve what?

Answer 35

multiple hosts

Question 36

why do some parasites change the behavior of their host?

Answer 36

to increase the likelihood that the parasite will be transmitted to the next host

Question 37

what can parasites affect

Answer 37

survival, reproduction, density of host population - directly/indirectly

Question 38

positive interactions

Answer 38

at least one species benefits and neither is harmed

Question 39

mutualism

Answer 39

positive interaction for both species involved

Question 40

commensalism

Answer 40

positive for one species, neutral (neither harmed nor helped) for other species

Question 41

2 fundamental features of community structure

Answer 41

1. species diversity 2. feeding relationships

Question 42

in some cases, a few species in a community exert strong control on _____________

Answer 42

that community's structure

Question 43

species diversity

Answer 43

variety of organisms that make up the community

Question 44

2 components of species diversity

Answer 44

1. species richness 2. relative abundance

Question 45

species richness

Answer 45

number of dif species in the community

Question 46

relative abundance

Answer 46

proportion each species represents of all ind. in the community

Question 47

communities w/ higher diversity are:

Answer 47

1. more productive - produce more biomass 2. more stable 3. can withstand/recover from environmental stresses 4. more resistant to invasive species

Question 48

invasive species

Answer 48

organisms that become established outside their native range

Question 49

trophic structure

Answer 49

feeding relationships between organisms in a community

Question 50

food chains

Answer 50

link trophic levels from producers to top carnivores

Question 51

trophic level

Answer 51

position an organism occupies in a food chain

Question 52

trophic levels from bottom to top

Answer 52

- primary producers - primary consumers - secondary consumers - tertiary consumers - quaternary consumers

Question 53

food web

Answer 53

group of food chains linked together forming complex trophic interactions

Question 54

does a species only play one role on one trophic level?

Answer 54

no - can play more

Question 55

how can food webs be simplified:

Answer 55

- group species w/ similar trophic relationships - isolate portion of community that interacts very little w/ rest of community

Question 56

how long is each food chain in a food web

Answer 56

only a few links long

Question 57

energetic hypothesis

Answer 57

length of food chain is limited by inefficient energy transfer

Question 58

how much of energy stored in organic matter at each trophic level is converted to organic matter at the next trophic level?

Answer 58

10%

Question 59

what can also limit the length of the food chain

Answer 59

carnivores tend to be larger at higher trophic levels - can't obtain enough food from small prey efficiently enough to meet metabolic needs