# Human Population Growth Worksheet Template

Human Population Growth
Name:
Introduction: Darwin’s first two observations in the exposition of Natural Selection involve
population ecology: Populations have the potential to increase exponentially, but usually they
remain constant in size. Both conditions are observed in nature and are associated with the
balance of (births + immigrations) minus (deaths + emigrations).
Key Concepts:
Population growth patterns
Factors influencing population growth
What’s due at the end of workshop next week:
This worksheet and graph with all of the questions answered 10 points
HOW DOES A POPULATION CHANGE?
Population size depends on how many (births + immigrations) minus (deaths + emigrations)
there are. Let’s look at four ways a population can grow.
For the following examples,
N = number of people in the population at any given time
N
= number of the original population
o
B = births (number of people joining the population)
D = deaths (number of people leaving the population)
t = time
A. EXAMPLE: The population remains constant over time (EQUILIBRIUM).
Imagine you are having a party in your living area. At the present time (N
), there are ten
o
people in your room. Every hour one person leaves and one person joins your party. How many
people are in your room three hours after the party started?
N(t) = N
+ (B-D)/hr *t
o
12
N(3) = 10 + (1-1)/hr *3hrs
10
8
N(3) = 10 people
6
4
This produces a population growth
curve that is a straight line with no
2
slope.
0
0
1
2
3
4
5
6
(1 point)
time (hours)
1. Use graph A. above to determine
how many people are in the room 5 hours after the party started.
2. Using the equation above, calculate how many are in the room 6 hours after the party
started. Does your calculation agree with the graph?