Unit 2: Population Ecology I and II

Question 1

Organismal Ecology

Answer 1

Organism’s interaction with environment (biotic and abiotic)

Question 2

Population Ecology

Answer 2

interactions between members of the same species with each other and their environment

Question 3

Community Ecology

Answer 3

interactions between populations and their environment

Question 4

Ecosystem Ecology

Answer 4

interactions between communities and the climatic conditions of an entire region

Question 5

Landscape Ecology

Answer 5

effects of spatial distributions in an area that can affect a species

Question 6

What are the three key characteristics of population ecology?

Answer 6

1. Range
2. Spacing patterns
3. Changes in size over time

Question 7

Match the following with either an (A) abiotic factor or (B) biotic factor.

Sunlight
Bacteria
Rainfall
Zebras
Viruses

Answer 7

Sunlight (A)
Bacteria (B)
Rainfall (A)
Zebras (B)
Viruses (A)

Question 8

What is the difference between a biotic component and an abiotic component?

Answer 8

Biotic components are living whereas abiotic components are non-living.

Question 9

What are the two types of checks on populations?

Answer 9

Density-dependent and density-independent

Question 10

Density-Dependent Factors

Answer 10

Checks on a population that are directly correlated to the size of a population

Question 11

What are 4 examples of density-dependent factors?

Answer 11

Disease
Competition
Predation
Parasitism

Question 12

Density-Independent Factors

Answer 12

Checks on a population that have no correlation to the size of a population

Question 13

What are 3 examples of density-independent factors?

Answer 13

Weather and climate
Pollution
Rapid habitat loss

Question 14

What are the three methods used by ecologists to study populations?

Answer 14

Demography
Population Growth
Population Dynamics

Question 15

Demography

Answer 15

Study of factors that determine the size of populations through time

Question 16

Population Dynamics

Answer 16

Interactions of demography and population growth

Question 17

Population Growth

Answer 17

Change in the number of individuals in the population per unit time

Question 18

What is the formula for population growth?

Answer 18

N/t = births - deaths

Question 19

A population of snakes has a growth rate of r = -0.07. What is happening to the population?

Answer 19

The population is declining.

Question 20

If r = 1.43, then the population is said to be _______.

Answer 20

Growing

Question 21

If a population is not exhibiting change in rate, what is its growth rate?

Answer 21

r = 0.00

Question 22

What are the characteristics of exponential growth?

Answer 22

• Population increases under ideal conditions
• Experiences rapid growth but this is not limitless as the carrying capacity will be reached

Question 23

True or False: a higher r indicates that a population is growing more rapidly

Answer 23

True

Question 24

A s-curve is indicative of which population growth curve?

Answer 24

Logistical

Question 25

A s-curve is indicative of which population growth curve?

Answer 25

Logistical

Question 26

In population ecology, N stands for what?

Answer 26

Population size

Question 27

In population ecology, K stands for what?

Answer 27

Carrying capacity

Question 28

Suppose a population has the following data. Calculate its logistical growth. N = 1653 K = 1493 r = -0.97

Answer 28

-172

Question 29

Match the following relation of N and K (letter) with its definition (number). A) N --> K B) N = K C) N > K 1) Growth rate is zero 2) Population growth slows 3) Population decline until K

Answer 29

A - 2 B - 1 C - 3

Question 30

What are r-selected populations?

Answer 30

Populations where: - Age of first reproduction is early - Life span is short - Maturation time is short - Mortality rate is high - Number of offspring is high - Number of reproductions per lifetime is low - No parental care - Size of offspring is often small

Question 31

What are K-selected populations?

Answer 31

Populations where: - Age of first reproduction is late - Life span is long - Maturation time is long - Mortality rate is low - Number of offspring is low - Number of reproductions per lifetime is high - Extensive parental care - Size of offspring is often large

Question 32

How do birth and immigration, as well as death and emigration, play a role in population dynamics?

Answer 32

Birth and immigration add individuals to a population, while death and emigration remove individuals from a population.

Question 33

What do the different values of R (net reproductive rate) mean?

Answer 33

If R > 1, growth is occurring If R < 1, decline is occurring If R = 1, population is in equilibrium

Question 34

A population has a higher proportion of its individuals living early on, not surviving late, reproducing early, and minimal parental care. Which type of survivorship best explains this?

Answer 34

Type III

Question 35

Under the Mark-Recapture method, how is total population size deterimined?

Answer 35

[(# of marked individuals in 1st catch) x (total # in 2nd catch)] / (# of marked recaptures in 2nd catch)

Question 36

What is an issue with the Mark-Recapture method?

Answer 36

Previously captured animals could learn to avoid traps or intentionally get caught to gain access to food

Question 37

What are the three types of dispersion patterns?

Answer 37

Clumped spacing Uniform spacing Random spacing

Question 38

Clumped Spacing

Answer 38

Most common dispersion pattern; resources tend to be clustered and social behavior may promote this pattern

Question 39

Uniform Spacing

Answer 39

Uniform spacing between populations/resources; competition may cause this and it may result from social interaction

Question 40

Random Spacing

Answer 40

Populations are randomly spaced and may occur where resources are common and abundant; rarest dispersion pattern

Question 41

Where do metapopulations occur?

Answer 41

Areas where suitable habitat is patchily distributed and is separated by intervening stretches of unsuitable habitats.

Question 42

Semelparity

Answer 42

All offspring are produced in a single reproductive event; individuals reproduce once before they die

Question 43

Iteroparity

Answer 43

Reproduction takes place in successive years or breeding seasons

Question 44

Human population best fits which growth model?

Answer 44

Exponential

Question 45

True or False: in humans, the fertility rate is increasing

Answer 45

False

Question 46

What is the main difference in human populations between developed and developing nations?

Answer 46

In developed nations, population is stabilized, while in developing nations the population is increasing

Question 47

What sociopolitical impacts play a role in human population?

Answer 47

- Availability to resources - Educations - Healthcare

Question 48

For humans, what is the average ecological footprint for one individual?

Answer 48

Roughly 5 acres

Question 49

What is a life table?

Answer 49

Summarizes the probability that an individual will survive and reproduce in any given year over the course of its lifetime.

Question 50

In a life table, what does nx mean?

Answer 50

Number alive

Question 51

In a life table, what does dx mean?

Answer 51

Number dying

Question 52

In a life table, what does lx mean?

Answer 52

Survivorship

Question 53

Type I Species

Answer 53

Most individuals die late in life

Question 54

Type II Species

Answer 54

Uniform birth and death rate over the entire lifetime

Question 55

Type III Species

Answer 55

Most individuals die early in life

Question 56

In a life table, what is mx?

Answer 56

Fecundity/Reproduction rate