Final Exam

Question 0

Resource competition v. Interference competition

Answer 0

Resource: Shared resource is in short supply; indirect interaction
Interference: Shared resource is usually in short supply; direct interaction

Question 1

2 Types of Competition

Answer 1

1. Resource Competition

2. Interference Competition

Question 2

Define Competition

Answer 2

One individual gains access to limited resources at the expense of another individual

Question 3

What is the Competitive Exclusion Principle

Answer 3

Populations of two species with identical niches cannot coexist indefinitely (there will be competition)

Question 4

What are the conditions for the Competitive Exclusion Principle?

Answer 4

One or more resources must be in short supply
The environment remains consistent
Must be a long enough time for equilibrium

Question 5

How can you explain competition in nature?

Answer 5

Resource Partitioning
Character Displacement
Environmental Instability

Question 6

Resource Partitioning v. Character Displacement

Answer 6

Resource Partitioning: 2+ species divide the resources to reduce competition
Character Displacement: competing species evolve traits to reduce competition

Question 7

What are the types of exploitation?

Answer 7

Predation, Herbivory, Parasitism, Disease, Parasitoid

Question 8

Hypothesized Dynamics of exploitation

Answer 8

Predator has negative effect on prey/host; Prey has positive effect on predator
Time lag between predator and prey

Question 9

What can we conclude from predator-prey interactions?

Answer 9

Predator-prey interaction is unstable without external influence

Question 10

What are the outcomes of predator-prey interactions?

Answer 10

Stable equilibrium
Stable cycles
Unstable cycles
Dampened oscillations

Question 11

What is the Evolutionary Arms Race?

Answer 11

Predator: sharp claws, enhanced vision
Prey: size, camouflage, enhanced hearing

Question 12

What is a prudent predator?

Answer 12

A predator that feeds at the maximum sustainable yield. “Cheaters” make this not happen

Question 13

What are the emergent properties of a community?

Answer 13

Diversity
Structure
Number of Trophic Levels
Number of links
Stability

Question 14

What are the measures of diversity?

Answer 14

Species Richness

Heterogeneity

Question 15

Species Richness v. Heterogeneity

Answer 15

Species Richness: # Species in a community

Heterogeneity: relative proportion of species

Question 16

How can you explain high and low diversity?

Answer 16

Habitat isolation and size (island example)
Resource Partitioning
Disturbance

Question 17

What is the intermediate Disturbance Hypothesis?

Answer 17

A communities diversity is the greatest when there is an intermediate amount of disturbances

Question 18

What is a keystone predator?

Answer 18

Predator whose removal results in a very different food web

Question 19

What is a super-organism?

Answer 19

Clumped distribution of species ie. Coral reef

Question 20

What is the facilitation mechanism of success?

Answer 20

Early species modify the environment and late species outcompete the early species

Question 21

What is the inhibition mechanism of succession?

Answer 21

Early species prevent colonization of late species by creating physical or chemical barriers, and late species arrive following the death of the early species

Question 22

What is the tolerance mechanism of succession?

Answer 22

All species colonize at the same time but late species outcompete the early species (not much evidence for this)

Question 23

What is an ecosystem?

Answer 23

A community and its physical and chemical environment

Question 24

What ecosystem has the highest Net Primary Productivity?

Answer 24

Ocean has highest followed by tropical rainforest

Question 25

What is the fate of fixed carbon?

Answer 25

Herbivory; metabolism (respiration); body tissue (growth + reproduction); death (leads to detritus)

Question 26

True/False: Energy flow is bidirectional

Answer 26

False. Energy flow is unidirectional

Question 27

True/False: energy stays the same through Trophic levels

Answer 27

False. Energy is lost each time it is transferred. Only about 10% of the energy is transferred

Question 28

How does carbon enter and exit the biotic compartment?

Answer 28

Enter through photosynthesis

Exit through respiration

Question 29

How does nitrogen enter the biotic compartment?

Answer 29

Nitrogen fixation, nitrification, then plant metabolism

Question 30

What is nitrogen fixation?

Answer 30

Process where N2 turns into NH4+

Question 31

What is nitrification?

Answer 31

Ammonia is converted into nitrite and nitrite is the converted into nitrate