community ecology - exam 4

Question 1

community

Answer 1

all populations of organisms living close enough together for potential interaction

Question 2

INTERspecific interacions

Answer 2

interactions w/ individuals of DIFFERENT species in the community

Question 3

coevolution

Answer 3

reciprocal evolutionary change in interacting species

Question 4

predation

Answer 4

+/- interaction

good for predator
bad for prey

Question 5

forms of predation

Answer 5

herbivory
carnivory
parasitism

Question 6

defenses agaisnt predators

Answer 6

escape

be hard to eat

annoy

be hard to see

mimicry

tell the truth (poison)

herd

be vigilant

mob predator

leave & regrow limbs

Question 7

batesian mimicry

Answer 7

a harmless species mimics a harmful species

Question 8

aposematic coloration

Answer 8

warning coloration

bright colors warns predators that they are poison

Question 9

mullerian mimicry

Answer 9

2 or more harmful species resemble each other

predators don’t have to learn multiple colorations

Question 10

predator adaptations

Answer 10

coevolution

acute senses

speed, agility, jaws, teeth, poison

ambush

attraction

Question 11

symbiosis

Answer 11

interaction between organisms of 2 different species that involves direct physical contact

Question 12

mutualism

Answer 12

+/+

both species benefit

Question 13

obligate symbiosis

Answer 13

when at least 1 of the partners cannot complete its life cycle on its own

Question 14

facultative symbiosis

Answer 14

partners do not necessarily require one another to survive &/or reproduce

Question 15

endosymbiotic

Answer 15

one organisms lives inside another

often obligatory

Question 16

commensalism

Answer 16

+/0

one benefits
the other is neither harmed nor benefits

usually not obligatory

Question 17

parasitism

Answer 17

+/-

one benefits
other suffers but doesn’t usually die

parasites adapt to very specific hosts

Question 18

competition

Answer 18

-/-

can occur when resources are scarce

Question 19

niche

Answer 19

the match of a species to a specific environmental condition

Question 20

when does interspecific competition happen

Answer 20

when niches overlap

Question 21

competitive exclusion principle

Answer 21

2 species that share the same limiting resource cannot coexist indefinitely

1 species will win @ the expense of another

Question 22

fundamental niche

Answer 22

if no other species existed, where would you live

bigger

Question 23

realized nich

Answer 23

where you’re actually found

smaller

Question 24

how can competitive exclusion be avoided

Answer 24

if 1 or both of the species evolve:

to use a diff resource
occupy a diff area of the habitat
feed during diff time of day

Question 25

resource partitioning

Answer 25

division of limited resources by species to help avoid competition

Question 26

character displacement

Answer 26

greater difference in a trait when 2 species co-occur than when 1 is present by itself phenotypic differences ex - same beak = more competition for food

Question 27

species richness

Answer 27

total # of species in a community

Question 28

relative abundance

Answer 28

proportion that each species represents

Question 29

Shannon Diversity Index

Answer 29

takes both species richness & relative abundance into account higher = greater diversity

Question 30

Shannon Equitability Index

Answer 30

metric used to assess how evenly the individuals are distributed among the different organisms present

Question 31

benefits of diversity

Answer 31

increased productivity better able to withstand & recover from disturbance

Question 32

biomass

Answer 32

total mass of all organisms in a habitat

Question 33

trophic level

Answer 33

organisms that share the same function in the food chain

Question 34

primary producer

Answer 34

photosynthesizer creates all energy that's passed up the food chain

Question 35

primary consumer

Answer 35

grazers herbivores

Question 36

secondary consumer

Answer 36

predators

Question 37

tertiary consumers

Answer 37

top predators

Question 38

food webs

Answer 38

more realistic model accounts for omnivores / animals that fulfill more than 1 role

Question 39

ecosystem engineer

Answer 39

changes species richness & diversity by changing physical environment

Question 40

dominant species

Answer 40

species in a community that are most abundant

Question 41

2 dominant species hypotheses

Answer 41

most competitive in exploiting limited resources most successful @ avoiding disease or predation

Question 42

keystone species

Answer 42

big imapct on community structure not necessarily abundant ex - sea otter, sea urchin, kelp

Question 43

top down control

Answer 43

populations of lower trophic levels are controlled by the organisms at the top

Question 44

bottom up control

Answer 44

driven by presence or absence of the producers

Question 45

trophic cascade

Answer 45

predators alter behavior of their prey thereby releasing next lower trophic level from predation

Question 46

trophic cascade example

Answer 46

increase big fish = decrease little fish decrease little fish = increase zooplankton increase zooplankton = decrease algae