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Investigating Microbial Growth

Hypothesis
If the bacteria contaminated petri dishes containing sterile nutrient agar are left in an incubator set at 37 ° C, then there should be a considerable amount of colony growth within the 48 hours because it is the optimal temperature for microbial growth. We presume that the more human visited areas such as the bathroom, store counter, and door handle will have a high bacteria influence where as the fishtank will be consierably less since it is cleaned regularly and no people touch it. The stove theoretically will have the least bacteria due to the extreme temperatures. 50% estimated coverage with a wide range of bacteria species.
Materials
Obtain 5 sterile cotton swabs and 5 sterile agar petri dishes along with a sharpie pen, tape, and an incubator. 
Swabs
Agar
Incubator
pen
Tape
Method
Open the swab package and wipe/drag the cotton tip along the desired surface making sure to contaminate the swab. After obtaining a sample using the cotton swab, open the petri dish and swipe the contaminated cotton swab along the agar surface. The swipes should span over most of the agar surface to evenly distribute the bacteria. Make sure to keep the swab and petri dish away from any alternate bacterial exposure, once successful with contaminating the dish close the lid and tape it shut. Label the dish using a wax pencil or permanent marker and place the dish into an incubator set to 37°C. Repeat this 5 times using separate sterile swabs and agar plates, be sure to swab different locations to obtain different results. After 48 hours examine the petri dish for bacterial growth.
Data/Results
Conclusion
Our original approximation of 50% coverage and a wide range of bacteria was disproved with an average coverage of 20.6% and only 4 visably different species of bacteria. Although we over estimated the growth-rate of most samples the fish tank sample successfully succeeded the estimated coverage at 70% and had a total of 4 visibly different colony species. We have come to the conclusion that bacteria do not actually thrive from constant human interaction, like a dirt path in the forest more contact will translate to less existing bacteria.
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