Gammarus Setosus Experiment

Abstract: The main focus of this lab is on animal behaviors in terrestial isopods, also known as pillbugs. There are many purposes to this lab experiment. First, these pillbugs are put into four different types of enviroments, also known as chambers, light v. dark, hot vs. cold, moisture vs. dry, and lastly shelter vs. open. In these different chambers, there are 10 pillbugs, 5 placed into each individual chamber and then observed for up to 5 – 10 minutes. In this lab we observed that pillbugs prefer light areas, hot temperatures, moist environments, and lastly sheltered spaces.

Just like the tiny sowbug the small one spent most of its time in the light area. The small sowbug was less concerned about being in the dark. Discussion- My hypothesis was not completely supported by the data.

Daphnia Magna are small crustaceans that are excellent for observing the effect of depressants on their nervous system. The purpose of this specific experiment is to observe the effect of ethanol, aspirin, and caffeine on daphnia’s heart rate. Not only do these chemicals affect heart rate, but they also affect the frequency of reproduction, number of eggs produced, and body structure. Pesticides similar to these chemicals can be released into the environment and daphnia re useful in monitoring toxicity levels. The agents being tested in this experiment can be administered to determine the effects of hormones, stimulants, antidepressants, and neurotransmitters.

This behavior was observed in all the three experiments and through the period of observation, isopods seemed to move to different sponges before they settled down behind one of them. The χ2 value was 0.03842932, df was 3 and hence the P value was less than 0.001 which proves that this result is not a result of random probability and is in fact significant and reliable. In Trial 2, the hypothesis was that most isopods would go to the sponge with sucrose solution and our hypothesis was proved correct through the experiment. It was observed that a majority (55%) of the isopods preferred sucrose relative to the other sources of moisture.

This predation was seen at Hastings Point, where the limpet’s main predator, Morula marginalba (mulberry whelk), was identified 25 times in the first 35m. To survive this predation, the limpet utilises its tough clutch on the rocks, defending itself against predators by trapping them under the rim of its shell, consequently killing or starving the

The starting population of the experiment contained 100 organisms that had 10 different Dottus Variengatus phenotypes. A multicolored-city board was used to simulate the environment where these organisms lived. To perform the experiment, groups of three were formed. The first member had to act as a new predator of the population, the second member was assigned to randomly disperse the colored dots on the board, help keep count of the consumed dots, and collect materials at the end of the experiment. The third member had to collect the prey from the predator, and help keep count until 25 dots were collected.

Students started off with a population of ten Skittlefish (skittles) on an orange reef (construction paper). The skittles had varying colors, and the adaptive trait being examined was the ability to blend in with the reef so the predators would not find them. The hypothesis that was thought up was that individuals’ survival was based on their location and coloring. The first year began with two of each color, and 5 Skittlefish were eaten that “year”. The ones eaten were two green, two purple, and one red.

Tradeoffs are a frequent occurrence in Nature. They describe the compromise between two optimal but frequently incompatible traits for an organism. Andrea Pomeroy and her team applied this concept of tradeoffs to the western sandpipers, Calidris mauri, of British Columbia Canada, with the trade off of their ability to forage for food against the costs of potential predation. The main idea examined by Pomeroy was to study the spatial usage (The measure of how intensely a site is used for foraging by the sandpipers) at Boundary Bay, to determine how the birds chose their stop over sites during migration based on the tradeoffs between food abundance and predation risks.

This one explanation full illustrates the importance of a balanced ecosystem and how the introduction of a predator can make sweeping changes in the

Loggerhead turtles are species generalists. Loggerheads compete with other carnivorous predators whose diets overlaps with theirs. For example, juvenile loggerheads and Kemp’s ridleys in waters around Long Island have substantial diet overlap. Interspecific competition also occurs for nest sites for beaches shared with other sea turtles species; however, this problem was likely greater in the past before modern turtle population declines. The diet of loggerheads includes many species that are harvested by humans and consequently decreases in food resources can result in sublethal effects in the form of decreased growth rates and reproductive output (Bjorndal 2003).

Insects are drawn to light instead of their natural night habits, congregating around streetlights and house lights. The decline in some insects then affects the circle of life in nature. Other repercussions in nature are the changes in nocturnal mammal’s and rodent’s activities, due to the presence of light. Some mammals and rodents are drawn to light and, therefore, end up being hit by vehicles or killed by predators. Other mammals and rodents avoid the light, and choose to move their homes and areas of roaming.

The probability of this is uncertain, as there is a possibility that loggerhead turtles will select different nest sites as warming increases, or rapidly adapt to the changed climate (Deeming and Ferguson 1989). However, a shift in nest site preference is not the most likely option for loggerhead sea turtles, which show strong nest site fidelity. In addition, because nesting females generally return to their natal beaches and there is a low gene flow between nesting assemblages, these populations that are genetically distinct are at risk for extirpation (Ehrhart et al. 2003). Additionally, the potential for loggerheads to choose suitable nest sites is limited by human activity.

“But most important, I suppose, my experiment has made me feel important-every atom in me, in everybody” (Zindel 109). In the book The Effect of Gamma Rays on Man-in-the-Moon Marigolds by Paul Zindel, the significant symbols is the marigolds and the gamma rays. The marigolds represent Tillie, the main character, and how her mother affects her life. Her mother, Beatrice, also is important since the gamma rays in the play represent her. These symbols help reveal the characters personalities and the theme in the work.

Joshua Rabideau 11/10/2016 BIOL 380 – Lab: Monday Black-Capped Chickadee Foraging Habits There are numerous organisms and interactions occurring within any ecosystem. Many times, the interactions between organisms and habitats are based on the energy needs of the organisms. In this experiment, a null hypothesis that the Black-capped Chickadee forages on various trees at random. Upon data analysis of the gathered information, it can be determined that the Black-capped chickadee were not choosing foraging sites at random. The results of a chi square test gave a value of 19,890 which is significantly larger than the 16.812 value needed to void the null hypothesis with six degrees of freedom; the probability that this variation was due to chance is less than .01.

This theory was created to explain and understand the relationship between a size of an area and the number species therein, as the name suggests. It was concluded from the experiment that as the area increases the number of species found within increases continuously less. If graphed we notice a curve hence the species-area curve. (Vreugdenhil, 2003) The curve is very different between