Community ecology

Question 1

Principle of allocation

Answer 1

when resources are devoted to one use, they cannot be allocated to another

Question 2

niche

Answer 2

the range of conditions a species lives in

Question 3

fundamental niche

Answer 3

the range of physical conditions that a species can tolerate (defines habitat)

Question 4

range of tolerance

Answer 4

the range of environmental conditions within which an organism can survive, grow, and reproduce

Question 5

realized niche

Answer 5

the range of physical conditions that a species actually occupies, given the constraints of biotic interactions

Question 6

treatment

Answer 6

transplant outside current range

Question 7

control

Answer 7

transplant inside current range

Question 8

range shift

Answer 8

occurs when the geographical location of a species changes its location

Question 9

range expansion

Answer 9

the process by which species increase its geographical distribution, usually by moving into new areas where it was not previously found

Question 10

range contraction

Answer 10

occurs when a species reduces its geographical distribution, either by withdrawing from certain areas or through local extinction

Question 11

Competition

Answer 11

the interaction between two species that has a negative impact on both species involved (aka both populations decrease)

Question 12

Exploitative competition

Answer 12

the indirect competition between individuals or species for limited resources within an environment

Question 13

Interference competition

Answer 13

the direct interactions between individuals or species that impede access of competitors to essential resources

Question 14

the competitive exclusion principle

Answer 14

states that if two species with identical niches compete then one will inevitably drive the other to extinction

Question 15

Temporary co-existence

Answer 15

both species continue to live in an area, but at lower #’s (lower carrying capacity)

Question 16

competitive exclusion

Answer 16

one of the species disappears from the area (usually not random - some species are better competitors than others)

Question 17

niche partitioning

Answer 17

both species continue to co-exist but they diverge to occupy diff ecological niches (realized niche changes = type of character displacement)

Question 18

foundation species

Answer 18

provide an ecological foundation for many other species, even though they might not benefit from the interactions

Question 19

keystone species

Answer 19

species with a disproportionately large impact on its environment relative to its abundance or biomass

Question 20

biomass

Answer 20

total mass of living organisms in a specific area

Question 21

mutualism

Answer 21

+,+

Question 22

consumption

Answer 22

+, - (predation, parasitism, herbivory)

Question 23

commensalism

Answer 23

+, neutral

Question 24

amensalism

Answer 24

-, neutral

Question 25

food web

Answer 25

ecological network that shows who eats whom and how much, aka the trophic relationships (diagram)

Question 26

trophic levels

Answer 26

a position in the food chain that represents a group of organisms sharing the same primary source of nutrition and energy
- primary producers
- primary consumers (herbivores)
- secondary consumers (omnivores, carnivores
- tertiary consumers (feed on secondary consumers, largest)

Question 27

ecosystem services

Answer 27

goods and services humans derive from the natural ecosystem

Question 28

humus

Answer 28

organic matter