Factors Influencing Population Growth

                          Playing "Oh Dear"

Round 1 of the game "oh dear" started off with two deers and habitat component such as: food, water and shelter.  ( Density dependent factors). The deers are placed on one side while the habitat components are on the other side, while the backs are facing each other. The deers decide what resource they want and the habitat components  decide what resource they want to be.  When the two groups face each other, the deers either walk or run (depending on if there is any competition among the dears) towards the resources (habitat components) and mate. Therefore, deer's resource (shelter, food or water) become a deer, because they've been feeding and they are able to reproduce. This process is repeated several times until there are more deers on one side and few amount of resources on the other.  If the deers don't find a resource they die. Then they will decompose and eventually become the resources. 
After the third and fourth round, the deers become nervous, since there are more dears and few resources. Therefore competition builds up between the dears as they compete among each other for resources. Deers run with full speed towards the resources!!!!

Round 2 is similar to round 1. However this time we have independent factors (factors that influence population regardless of density. These include hunters, poor weather and predators). This time the entire class is divided into two groups: deers and resources. In the first round, there are no other resources for dears other than water. So all the other deers (searching for food or shelter died) become resources. The reason for this is, the environment is effected by flood, therefore there is only water left. In the second round, due to forest fire (deforestation) all the deers in search for shelter died because the fire ruined the homes. 
In the third round, due to drought that had occured in the environment, deers in search for water lost their lives. In the fourth round, some of the deers die before even starting the search for resources. So they decompose and became resources. Since there are a fewer amount of deers left competition was less between them. In the next round, two hunters are placed in the middle of the field ready to hunt deers. For every two deers hunted, one deer would become hunters and the other would become resource. If the number of deers caught were odd, one of them would automatically become resource.  


 So what did I learn ?????

• In the end the resources survive
• Density dependent factors include water, food, shelter
• Exponential population works under ideal conditions. When we have  an abundance of resources
•  At  carrying capacity (k), resources become completed and the deers will have nothing to eat, so their population will die
• The reason population populations eventually stop growing is caused by density dependent and density independent factors
• As population density (number of individuals within a certain volume ) increases, birth rate declines ---> less population, and death rate increases---> more competition, less resources
• Negative feed back----> prevents unlimited population growth. When we reach a certain capacity it affects the population so that it decreases, this will reset everything. Decrease in population would increase the amount of resources ----> wave pattern in graph
• Density independent factors (flood, drought, disease, hunting and predators) are unrelated to population density. There is no feed back to slow down population. Here is when we see significant changes. Extinction ---> when we have intervention with no feedback and no regulation, we can loose populations.
• Right now, humans still have enough resources to flourish. However it's only a matter of time for us to reach human carrying capacity. 
• Resource limitation can stop population growth
• Interspecific competition is competition between species.
• Due to predation or insufficient amount of resources, animals will leave their territory
• Everything is in balance. The predators need the prey.  The prey need resources. We can't have too much of something because that will create disorder 

* This game was not only fun, but it also was very helpful in learning the concepts related to factors affecting population growth. It really got the students involved, and helped in building a deep understanding :)