Population Ecology

Question 1

What is population ecology?

Answer 1

• science that deals with measuring changes in population size and composition
• identify the factors that cause the changes

Question 2

It consists of all the individuals of a species in a given area

Answer 2

Population

Question 3

It describes the age distribution of individuals, and how those individuals are spread over the environment

Answer 3

Population structure

Question 4

Why is it important for scientist to describe natural populations?

Answer 4

• to asses the health of population
• to determine the endangered or threatened status
• to predict the population dynamics

Question 5

• study how and why population size changes over time
• study the factors affecting growth, stability and decline of populations

Answer 5

Population Dynamics

Question 6

3 phases in life cycle

Answer 6

• growth
• stability
• decline

Question 7

Characteristics of Dynamics

Answer 7

• size
• density
• dispersal
• immigration
• emigration
• births
• deaths
• survivors

Question 8

The _____ of a population is measured as the number of individuals per unit area

Answer 8

density

Question 9

The _______ of a population is the patten of spacing among individuals within the geogrpahic boundaries

Answer 9

dispersion

Question 10

It is a way to estimate the size of a population

Answer 10

Mark and recapture method

Question 11

Three general patterns of population distribution

Answer 11

• Clumping
• Uniform distibution
• Random dispersion

Question 12

• also known as aggregated distribution
• individuals aggregate in patches

Answer 12

Clumped distribution

Question 13

Clump Distribution
Caused by:

Answer 13

environment where the resources concentrated in patches

Question 14

Clumped Distribution
Other factors:

Answer 14

• mating
• limited seed dispersal

Question 15

Clumped Distribution
Importance:

Answer 15

• for protection
• reducing competition
• increasing feeding efficiencies

Question 16

• patterm of equallyspaced individuals
• used the resources found immediately around them

Answer 16

Uniform Distribution

Question 17

Unifrom Distribution
Caused by:

Answer 17

the ability to survive anywhere in the habitat

Question 18

Uniform Distribution
Importance:

Answer 18

able to set up the zone of territories for feeding, nesting, breeding

Question 19

Individuals in a population are spaced all over an area in a way that in unrelated to the presemce of others

Answer 19

Random Dispersion

Question 20

Random Dispersion
Spacing pattern:

Answer 20

based on total unpredictability

Question 21

Random Dispersion
Caused by:

Answer 21

the ability to live anywhere in a given area except, they are limited to grow whenever they are first set root (for plants)

Question 22

3 factors to determine population changes

Answer 22

• births
• deaths
• migration (immigration & emigration)

Question 23

Population of organism able to change ____ ____

Answer 23

over time

Question 24

Increase in population size usually due to _______ (birth rate)

Answer 24

natality

Question 25

Decrease in population size as a result of ______

Answer 25

mortality

Question 26

Population growth can be describe by using a growth curves, what are those?

Answer 26

- Exponential Growth - Logistic Growth

Question 27

It is called an S-curve necause of its shape

Answer 27

Growth curve

Question 28

Factors that tend to reduce population growth rates

Answer 28

Environmental resistance

Question 29

- the growth rate is always positive - NO upper limit to population size

Answer 29

Exponential Growth

Question 30

- mode of population that assume birth rate and death rate remain constant over time - describing an idealized population in an unlimited population - ignoring immigration and emigration

Answer 30

Exponenetial Growth Curve

Question 31

The result in exponential growth

Answer 31

b >d , r > 0

Question 32

Population growth is therefore regulated by _____ ______ (K), which is the maximum stable population size a particular environment can support

Answer 32

carrying capacity

Question 33

Population Growth Rate

Answer 33

- Logistic Growth Rate - Carrying Capacity

Question 34

- S-shaped curve - the rate of population growth slows as the population size approches carrying capacity, leveling to a constant level

Answer 34

Logistic Growth Rate

Question 35

Factors influencing population density

Answer 35

- interaction of density-dependent factors - interaction of density-independent factors

Question 36

Density-dependent Factors

Answer 36

- limiting resources (eg., food & shelter) - production of toxic waste - infectious disease - predation - stress - emigration

Question 37

Density-independent Factors

Answer 37

- severe storms and flooding - sudden unpredictable severe cold spells - earthquakes and volcanoes - catastrophic meteorite impacts

Question 38

General types of population fluctuations

Answer 38

1. Stable 2. Irruptive 3. Chaotic Behavior 4. Cyclic

Question 39

Population size fluctuates slightly above and below carrying capacity

Answer 39

Stable

Question 40

General types of population fluctuations: Stable, usually found in

Answer 40

- undisturbed areas - little change in climate

Question 41

- a population explosion but then rather return to a lower size rather than quickly - impacted by favorable weather, increase in food supply, decrease in predators

Answer 41

Irruptive

Question 42

Irregular changes in size with no real pattern seen

Answer 42

Chaotic Behavior

Question 43

Changes occur in a pattern over a period of time

Answer 43

Cyclic