Competition

Question 1

Effects of competition on population size may only be seen under conditions of

Answer 1

resource limitation

Question 2

What is competiton?

Answer 2

a negative-negative interaction that harms all “players” while it is going on

Question 3

What is resource competiton?

Answer 3

indirect competition by exploitations of resources (winner is better than competitors)

Question 4

What is interference competition?

Answer 4

direct competition by interception of resources (winner excluded competitors)

Question 5

What are examples of interference competition?

Answer 5

allopathy, territoriality, preemption

Question 6

What is allopathy?

Answer 6

chemicals produced by plants or microorganisms that have effect growth, development, and distribution of other plants and microorganisms

Question 7

What is preemption?

Answer 7

species competing for limited space

Question 8

What is a fundamental niche?

Answer 8

all biotic and abiotic factors that are within the tolerance range of a given species

Question 9

What is Hutchinson niche?

Answer 9

multi-dimensional “map” of all the environmental conditions that a species is able to tolerate (maintain a stable population

Question 10

What is a realized niche?

Answer 10

the actual range of abiotic and biotic factors occupied by a given species when in competition with others, or when limited by predation or parasitism

Question 11

Is fundamental or realized niche always smaller?

Answer 11

fundamental

Question 12

What is the competitive exclusion principle?

Answer 12

when 2 species fundamental niches are too similar, one will drive the other extinct

Question 13

What is intraspecific competition?

Answer 13

among members of the same species

Question 14

What does intraspecific competition decrease?

Answer 14

access to resources and leads to more deaths and less reproduction

Question 15

In intraspecific competition, when is average fitness per individual lowered?

Answer 15

at high densities

Question 16

What is interspecific competition?

Answer 16

among members of at least 2 different species

Question 17

What are births equal to at carrying capacity?

Answer 17

deaths

Question 18

Lowering resources lowers what and allows for what?

Answer 18

lowers K and allows for competition at lower densities

Question 19

When is there the highest level of intraspecific competition?

Answer 19

when population is near or at K

Question 20

What does phase plane diagram plot?

Answer 20

plot of population sizes of 2 competitors as they change over time

Question 21

What do zero growth isoclines show?

Answer 21

show when population growth of species 1 and 2 is zero

Question 22

What are the 4 possible outcomes of competition?

Answer 22

• species 1 wins
• species 2 wins
• stable equilibrium
• unstable equilibrium

Question 23

What does graph look like when species 1 wins?

Answer 23

lines don’t cross, species 1 line above species 2

Question 24

What does graph look like if species 2 wins?

Answer 24

lines don’t cross, species 2 line above species 1 line

Question 25

What does stable equilibtrium graph look like?

Answer 25

K1/alpha1,2 above K2

Question 26

What does unstable equilibrium look like?

Answer 26

K2 > K1/alpha 1,2

Question 27

What competiton is more important for stable equilibrium?

Answer 27

intraspecific

Question 28

What competition is more important for unstable equilibium?

Answer 28

interspecific competition

Question 29

What other factors can modify competition outcomes?

Answer 29

predations, environmental conditions

Question 30

What is metanalysis?

Answer 30

competition is most important for herbivores and filter feeders, lowest for deposit feeders

Question 31

Species able to coexist may be due to?

Answer 31

• environmental variation
• character displacement or niche diversification
• predations, herbivory, disturbance

Question 32

What does evolutionary change lead to?

Answer 32

lowered competition

Question 33

What does predation, herbivory, and disturbance lead to?

Answer 33

keeps N’s low, preventing competition

Question 34

What is spatial environmental variation?

Answer 34

variation across physical environment

Question 35

What is temporal environmental variaiton?

Answer 35

changes in environment over time