Chap4 Deer growth Example

Question 1

The model represents a deer population which is assumed to live in an environment which is large enough for not restricting the growth of the population. We also assume that only births but no deaths are occurring in that population. The population’s age structure is also neglected. Which type of growth is observed ?

Answer 1

Exponential Growth

Question 2

Draw the cuasal loop diagram for this system. What type of feedback is in there, why ?

Answer 2

Question 3

Draw the Stock and Flow diagram.

Answer 3

Question 4

If we change the initial population size, how does the curve of number of deers change, how does the doubling time change ?

How about changing the growth rate how would that influence te curve and doubling time ?

Question 5

Try to guesstimate the population size we would have if this growth process would be going on for 50 years. After that, change the simulation time accordingly (Menu Model/Settings, Final Time = 50) and run the model again. How near was your guess?

Answer 5

It’s exponential growth, what we get after 50 years is a huge number. N50 = N0*e^( 0.3*50) = 326.9 Mio