Growth Patterns
Factors Affecting Populations
Survivorship
Demographics MATH
Potpouri
100
What shape does a logistic growth curve have?
What is S shape
100
What type of survival strategy is defined by organisms that are fairly large, mature slowly, live fairly long, and care for their offspring.
What is K selected species.
100
Which survivorship curve demonstrates a mortality rate that is more or less constant with age?
What is type II.
100
The number of individuals per unit area is the population's ______________.
What is density
100
The doubling time for a population with a growth rate of 2% is ____________ years.
What is 35 years.
200
What shape does an exponential growth curve have?
What is J shape
200
What type of survival strategy is defined by organisms that are are opportunistic pioneers and do not care for their offspring.
What is r-selected
200
Which survivorship curve is typical for organisms that have a large number of offspring with only a few surviving to maturity.
What is type III.
200

A municipality with a total population of 80,000 recorded 1,120 live births and 640 deaths over the course of one year. What is the Crude Birth Rate (CBR) for this population?

14 births per 1000. 

Crude birth rate is calculated by dividing total births (1120) by total population (80,000) and multiplying by 1000 (because crude birth rate is the # births for every 1000 people). resulting in 14 per 1,000.

200
A population growing at 1% per year should double in about _____________ years.
What is 70.
300
Define exponential population growth.
What is increasing population size at an ever increasing rate
300
Widespread starvation would be an example of density dependent/density independent population control.
What is density dependent
300
Which survivorship curve shows a high juvenile survival rate, high survival in reproductive ages, and a tendancy for most individuals to reach old age.
What is type I
300

A national population has a Crude Birth Rate (CBR) of 22 per 1,000 and a Crude Death Rate (CDR) of 7 per 1,000. Assuming net migration is zero, what is the annual population growth rate (r)?

1.5%

Subtracting CDR (7) from CBR (22) gives net increase of 15 per 1,000. 

Dividing 15 by 10 converts this rate to a percentage of 1.5%.

300
A network of distinct but interacting populations is called a ______________________.
What is metapopulation.
400
Define logistic growth.
What is rapid growth when conditions are good, then slowed growth as the population approaches carrying capacity.
400
What survival strategy (k or r) is defined by organisms that produce many offspring in a short period of time and have low survivorship early in life.
What is r-selected
400
Which survivorship curve is typical of trees that experience a high early mortality, but once established live a long time.
What is type III
400

A county of 250,000 inhabitants reported 1,500 births, 750 deaths, 200 immigrants, and 100 emigrants during a 6-month observation period. Assuming these rates remain constant, what is the annual population growth rate (r)?

0.68%

Net gain over 6 months is (1,500 + 200) - (750+100) = 850 people. Doubling this yields an annual net gain of 1,700 new people over the year. 

Dividing 1,700 by 250,000 and multiplying by 100% gives 0.68%

400
Why is Russia's population declining?
What is the standard of living has decreased leading to higher death rates & lower birth rates.
500
Define Carrying Capacity.
What is the maximum population size that can be supported by the available resources on a long term basis.
500

A nature reserve spanning $4,500hectares is home to a population of 1,800 bison. What is the population density of bison in the reserve in bison per square kilometer? (1 km^2 = 100hectares)

40 bison / km. 

Converting 4500hectacres to km2 = 45 km2. divide 1800 bison / 45mk2 = 40 bison/km2

500
What type of survivorship curve do humans have?
What is type I.
500

An island population is growing at a constant annual growth rate of 2.5%. According to the Rule of 70, how many years will it take for this population to double in size?

28 years 

RULE of 70 formula: Doubling Time = 70/r

70/2.5 = 28 years

500
Summarize the human population theory held by Thomas Malthus.
What is humans would outstrip resources and then suffer starvation and misery.
M
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