1. 53.2 Exponential Growth Model
Population Ecology
53.2 Exponential Growth Model

2. Population Density
The amount of individuals per unit area

4. Population Density Practice
Watch your math! ?
Suppose the population density of a sample of deer is 55 per square kilometer.
Assuming that the population size would be if the deer encompassed an area that was 20km by 20km?
If 300 blue jays were found in a 20 hectare plot. How many blue jays per hectare?

5. Describes a population growth in an IDEAL environment
What might limit the growth of the bacteria?

7. Variables N = population size t = time
dN (delta N) which means the change in population
dt (delta t) which means the change in time
B = births
b = birth rate
D = deaths
m = mortality rate
Class
Group A
Group B
Class 1 82 95
Class 2 76 88
Class 3 84 90

8. There are 2000 mice living in a field
There are 2000 mice living in a field. If 1000 mice are born each month and 200 mice die each month, what is the per capita growth rate of mice over a month? Round to the nearest tenths.
N=2000
r= =800
800/ =0.4
r= Births-Deaths
Per capita means r/N

9. Find birthrate and deathrate
17 births in a population of 1500,
what is the birthrate?
8 deaths in a population of 1500
What is the deathrate?

10. Model: If we know the birthrate and the population, can you find the number of births?
Using the birthrate in India in 2011, determine the number of births in 1.3 billion people.
B = b N
D = m N

11. Revise the model
Population increasing or decreasing?

12. How to figure the Amt of time to Double A Population

13. Add a Slide Title - 5

15. Calculate the following parameters for each population
Calculate the following parameters for each population. Round each to whole number or hundredth where applicable .
Parameter Population A Population B
B (births during time interval
D (deaths during time interval
b (per capita birth rate) /500=0.20
d (per capita death rate /500=0.04
r (per capita rate of increase =0.16 or (100-20)/500

16. N(1+r)t Time (year) Population Size 0 500
1 (.16)(500)+500 = r(N)+N or
(.16) (1+.16)2 3 4 5
N(1+r)t

17. Q: growth rate = dN/dt = rN, r = b-d; dN/dt = rmaxN(K -N/K)
A hypothetical population has a carrying capacity of 1,500 individuals and rmax is 1.0.
a. Fill out the following table:
Population size N Population growth rate r 1,600
1,750
2,000
b. What is happening to this population? Why?

18. Population Size Population Growth
(1.0)(1600)[( )/1500] -107
(1.0)(1750)[( )/1500] -292
(1.0)(2000)[( )/1500] -667

19. TEST-Study your BILL –”Knowing is not enough: we must apply
TEST-Study your BILL –”Knowing is not enough: we must apply. Willing is not enough: we must do. Johann Wolfgang von Goethe
Feeding Scenerio
Task 1
Animal Behavior
Innate vs Learned altruistic
Proximate vs Ultimate
Population Ecology
Exponential vs logistic density dependent and independent limiting factors negative feedback
Survivorship Curve life history
Population dispersion r and k
Multiple Choice (15)
Grid in Math (2)
Population density
Per capita growth rate
FRQ-long-experimental design on behavior (1)
Taxis vs kinesis and interactions
FRQ-short (3)
Solve data table logistic and exponential scenario
Age structure