NS202: Ecological Niche

Jane Choi Ani Galtian Joung Soo Han Bo Kyung Kim Description of Video Our movie clearly shows the procedure and results of the lab. It depicts how the different environments the shrimp were put in affected their survival. We used pictures to show each step of the procedure of the lab, by showing the setup of each test tube. To expose one of the tubes to different shades of light, we wrapped half of it with black tape. Using the other test tube, we tested the reaction of the shrimp to light, but shining a light on one of the edges of the test tube, which was completely covered with black tape. We also show the results we received, and include graphs plotting the data. Results and Analysis This lab investigates the adaptability of organisms to certain environments. Organisms which are better suited for selective pressures in an environment will survive and reproduce, while those that are not will die. The objective of this lab was to observe the fundamental niche of brine shrimp. By looking at the variability of the reactions of shrimp to different stimuli, we could understand what conditions they were best suited for. We hypothesized that the shrimp would be more comfortable in the dark, and that they were better suited for cool temperatures. Throughout this experiment, we tested how the shrimp reacted to different temperatures, and shades of light. We also had a control group. Our results were successful in showing the reactions of the shrimp to these different stimuli. In the control tube that was in room temperature, the shrimp were evenly distributed at the end of 20 min. The numbers of individuals in the 4 sections of the tube were thirteen, twelve, eleven, and fifteen. The results of the tube that was exposed to different levels of temperature however, were quite different. In the section of the tube that was the warmest, at 40.2 degrees Celsius, there were only four shrimp, and all four were dead. In the next section, which was 29.7 degrees Celsius, there were three alive shrimp, and one dead. The third section was 25 degrees Celsius, and it included seven alive, and one dead shrimp. Finally, the last section, which was the coolest, at 24.9 degrees Celsius, included four alive shrimp. By looking at these results, we can see that most of the shrimp tried to move towards the cooler area of the tube. More than 50 % of the shrimp that were left in the warmer half of the tube died. Thus, we can see that the niche of shrimp would have to be a cool area. The results of the tube that was exposed to different levels of light were slightly different. No shrimp were dead in any areas of the tube. However, most of the shrimp swam to the darker half of the tube. In total, there were twelve shrimp in the darker half and seven shrimp in the lighter half. These results show that even though the light difference was not fatal to any of the shrimp, they prefer to be in darker environments. One area of this experiment that could have allowed for error is when we tightened the screw clamps own on four sections of the tubes. If we had not tightened them all down together, some of the shrimp could have moved to different sections of the tube. Thus, by looking at our results, we can realize that they may not be 100% accurate. Through this experiment, we realized that shrimp prefer cooler and darker environments, by their movements to different areas of the tubes. Our hypothesis was correct in our assumptions that they would prefer these types of environments. This experiment was overall very affective in investigating the niche of brine shrimp.