chapter 54

Question 1

community

Answer 1

a group of populations of different species living in close enough proximity to interact

Question 2

interspecific interactions

Answer 2

competition, predation, herbivory, paratism, mutualism, commensalism

Question 3

competitive exclusion

Answer 3

local elimination of the inferior competitor, often a reproductive advantage causes this

Question 4

ecological niche

Answer 4

the specific set of biotic and abiotic resources that an organism uses in its environment.

Question 5

resource partitioning

Answer 5

the differentiation of niches that enables similar species to coexist in a community, different species will live in one place and separate the resources accordingly so there isn’t competition, ex. dominican republic lizards

Question 6

character displacement

Answer 6

the tendency for characteristics to diverge more in sympatric than in allopatric populations of two species

Question 7

exploitation

Answer 7

any interaction in which one species benefits by feeding on the other species, which is harmed by the interaction. ex. predation, herbivory, paratism

Question 8

predation

Answer 8

interaction between species in which one species kills and eats the other

Question 9

predator adaptations

Answer 9

claws, teeth, fans, stingers, poison

Question 10

prey adaptations

Answer 10

coloration- cryptic (camo) mimicry(batesian vs mullerian), poisons, behavioral adaptations

Question 11

prey behavior adapptations

Answer 11

hiding, fleeing, schools/groups, self defense, alarm calls

Question 12

herbivore adaptations

Answer 12

chemical sensors, offactory, specialized teeth, specialized digestive system

Question 13

plant adaptations

Answer 13

molecule level defense, cellular level defense, organ level defense

Question 14

paratism

Answer 14

where one organism derives nourishment from a host

Question 15

mutualism

Answer 15

interspecific interaction that benefits both species

Question 16

commensalism

Answer 16

an interaction where one species benefits and the other is neither harmed nor helped

Question 17

batesian mimicry

Answer 17

harmless species mimics a harmful species it is not closely related to

Question 18

mullerian mimicry

Answer 18

two or more species will resemble eacother, one is unpalatable

Question 19

endoparasites

Answer 19

parasites that feed on the internal body of their host

Question 20

ectoparasites

Answer 20

feed on the external surface of a host

Question 21

positive interactions

Answer 21

a term that refers to an interaction in which at least one species benefits and neither is harmed

Question 23

species diversity

Answer 23

the variety of different kinds of organisms that make up the community, deals with species richness and relative abundance

Question 24

species richness

Answer 24

the number of different species in the communityr

Question 25

relative abundance

Answer 25

the proportion each species represents of all individuals in the community

Question 26

importance of diversity

Answer 26

more productive and more stable, better able to withstand and recover from environmental stress, more resistant to invasive species

Question 27

energetic hypothesis

Answer 27

suggests that length is limited by inefficient energy transfer, explains why food chains are so short because energy is so low at the end

Question 28

dynamic stability hypothesis

Answer 28

proposes that long food chains are less stable than short ones

Question 29

dominant species

Answer 29

species that are the most abundant or that collectivley have the highest biomass, example is american chestnut tree, can have large effecst and can not

Question 30

keystone species

Answer 30

not usually abundant in a community but they exert a strong control, example is coral

Question 31

ecosystem engineers

Answer 31

species that dramatically alter their environment, ex. beaver

Question 32

food web

Answer 32

a group of food chains that are linked together

Question 33

trophic structure

Answer 33

the structure and dynamics of a community depend on the feeding relationships between organisms. the transfer of food energy upward from its source in plants and other autotrophs

Question 34

trophic level

Answer 34

the position an organisms occupies in a good chain

Question 35

bottom up model

Answer 35

a unidirectional influence from lower to higher trophic levels, vegetation to herbivores. increasing plant growth will increase biomass.

Question 36

top down model

Answer 36

predation mainly controls community organization, also called trophic cascade model

Question 37

pathogens

Answer 37

alter community structure locally and globally

Question 38

zoonotic pathogens

Answer 38

have been trasnferred from other animals to humans

Question 39

vector

Answer 39

how the transfer of pathogens can be direct or thorough an intermediate species

Question 40

intermediate disturbance hypothesis

Answer 40

states that mdoerate levels of disturbance foster greater species diversity than high or low levels of disturbance