Chapter 11 - Population Growth

Why might average rates of dispersal be misleading? (Ask) (Chapter 10 Review Question)

Ask

A stable meta-population implies no sub-populations are declining, true or false? (Chapter 10 Review Question)

False

What type of Survivorship curve best describes a typical plant?(Chapter 10 Review Question)

Type 3

What might we infer from an age distribution that is almost entirely young? (Chapter 10 Review Question)

The population will exhibit rapid growth

What is the equation for population size?

Nt = Nt-1 + B + I - D - E

Explain each factor within the population size equation

Nt-1 = Initial Population size

B = Births

I = Immigration

D = Deaths

E = Emigration

What is the equation for Geometric Population growth?

Nt​=N0​λA^t

Explain each factor within the Geometric Population growth equation

N0 = Population size at time 0

λ = Average number of offsprings for one individual

t = time passed

Where may we see a Geometric Population growth?

A population with abundant resources, few limiting factors, and generations do not overlap

Is the Geometric Population growth realistic?

HAIL NAH DAWG

What is the equation for Exponential Population growth that expresses population change as PRODUCT OF r and N

dN/dt = rN

Explain all the factors for Exponential Population growth that expresses population change as PRODUCT OF r and N

dN = Change in number

dt = Change in time

r = Per capita rate of increase

N = Number of Individuals

What is the equation for Exponential Population growth that CALCULATES FOR POPULATION SIZE

Nt=N0e^rt

Explain all the factors for Exponential Population growth that CALCULATES FOR POPULATION SIZE

Nt = Number at time t

N0 = Number at time 0

e = natural log

r = Per capita rate of increase

t = time passed

Where may we see Exponential growth?

A population with abundant resources, few limiting factors, and generations overlap

What is the equation for Logistic Population growth?

dN/dt = rN (1 - N/K)

Explain all the factors for the Logistic Population growth equation

dN = Change in number

dt = Change in time

r = Per capita rate of increase

N = Number of Individuals

K = Carrying capacity

What happens to Logistic growth when N approaches K?

Population growth stops

Which type of population growth is the most realistic?

Logistic Population Growth

What are density-dependent factors?

Factors whose effects increase with population size, such as competition, predation, and disease.

What are density-independent factors?

Factors that affect populations regardless of their size, such as floods, droughts, and fires.

How do wet years affect Galápagos Finches?

Wet years lead to more food, resulting in higher survival and reproduction rates.

What happens to Galápagos Finches during dry years?

Food scarcity during dry years leads to population crashes.

What impact do extreme wet years have on cacti and finches?

They cause abiotic damage (like rot) and biotic damage (from vines and birds), leading to delayed recovery.

What is the distribution pattern of the human population?

Humans tend to have a clumped distribution, concentrated along coasts, valleys, and river systems.

What is the population density comparison between Singapore and Alaska?

Singapore has a density of ~8,000 people/km², while Alaska has <1 person/km².

What is the global trend in human population growth?

The trend is moving from exponential growth towards logistic growth, but it is uneven by region.

What factors contribute to rapid population growth in the Southwest US?

Rapid growth is due to migration and economic factors.

What kind of growth is this?

Geometric

3 multiple choice options

What kind of growth is this?

Exponential

3 multiple choice options

What kind of growth is this?

Logistic

3 multiple choice options