Ecology Lab Report

Ecology Lab Report Introduction An organism has several ways to avoid being prated upon. One way to avoid this is to practice crptis. Crypis is the action of organisms avoiding predation by blending in with their backgrounds and matching the color pattern of a bark, twigs or leaves. Palatable animals often utilize this strategy as well. Another type of defense is aposematism or warning coloratio. Organisms that produce noxious chemicals or accumalate them from food plants, advertise the fact that they are harmful with conspicous color patterns.

Mimicry is the resemblence of an organism toward some other organism or an object inthe enviroment, evolved to decieve predators or prey into confuding the organism with that which it mimics. The prey involved within this experiment utilized mimisry as their defense stategy. Batesia mimicry, Mullerian mimicry, and aggressive mimicry are all various forms of mimicry. Batesian mimicry is a resemblance of an unpalatable species (model) by an edible species (mimic) to decieve predators. Mullerian minicry is a mutual resemblance of two or more conspicuousyly marked upalatable species to enhance predator avoidance. Aggressive mimicry is a tactic that enables predators to avoid being detected by their prey or even to attract prey. The type of mimicry that was utilized within this experiment is Batesian mimicry.

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The purpose of thsi experiment is to observe predators or in this case birds, and determine whether or not mimicry developed based on the fact that the birds learned about what was really going on. Mimicry doesn’t always develop,. The predator must be smartiin order to realize that some are tasteful, while others are distasteful. Our predators can determine this by realizing that a color strategy is being put to use. The null hypothesis for this experiment is that if the don’t eat or remove most of the red larvae which happens to be 100%palatable, by the end of the week, then they did not realize that mimicry has occured.

These hypothesis are based on the assumption that the birds realized that the red larvae are more tasteful , while the blue and lime larvae were often distasteful. The focus of this experiment is to find out whether or not mimicry developed and whether the birds either learnt from the effects of mimicry or caught on to the color pattern. Materials and Methods The procedure that was utilize from this experiment was very time consuming and involved an assortment of small procedures. The first step was to decide upon the different colors of the food, and which speculate on whch colors would be most efficient for the experiment. In our case we choose red,which represented a kind of dangerous color, blue which was still dangerous but a little more attractive than red and lime which seemed like a nice friendly color. After than the ratios between the models were agreed upon based upon what we thought the colors would represent toward the birds.

The pattern that was used is pattern A. The red color had 100% mimicry, (palatable) and 0% for models (unpalatable). The blue color had 75% mimicry (palatable) and 25% for models (unpalatable). The lime had 25% mimicry and 75% for models (unpalatable). After that decision making the class broke up into different groups to facilitate the larvae making process.

The class divided into mixers, cutters,those that would make the charts fort what food would be place outside the food net and various other job titles. The mixers had to mix lard with 1.66g as much flour, quinine sulfate, to give the unpalatable taste, and food coloring in order to produce the larvae. After all the mixing was done it was then put into the refrigerator. Shortly after, the different lard combinations began to be placed out on wax paper awaiting the cutters. The cutters began cutting the lard combinations into reasonable sizes for the predators to feed upon, about 1.5cm.

The palatable and unpalatable were distiguished by the by the addition of quinine sulfate to the unpalatable portion. It was paramount that the students handeling the unplatable, didn’t deal with the palatable larvae for this could some how utler the results if there were more unpalatable ones than there were supposed to be. The rest of the class was to create random arrays to which the food was to be placed. These arrays are specific intructions as to where each larvae was to be placed. For example blue unpalatable would be next to the lime palatable.

By this idea, each day would have a different deployment and retrieval data. Every student was then assigned to a specific time slot, so they could either deploy the larae, or retrive the remaining data, or both deployment and retrieval on the same day but diffrenet times. The procedure of this experiment was veru time consuming, but the team effort in the class realy simplified the procedure in numerous ways. The materials for this experiment were also numerous. This experiment required water proof paper to write down data from the retrieval and deployment, in case if it rained and a thermometers to moniter the experiment.

A feeding tray was used to deploy the food outside in the bird feeder. A large mixing bowl was used for mixeing the lard and flour, while meduim size bowls were used for mixing quinine sulfate and the required colors. Cookie pressors were utilzed for seperating the paltable from the unpalatable and making them ooze out into single rows in oerder to be measured by 15 cm rulers into eatable pieces and then cut with razor blades. Weighing trays spoon and top loading balances were used to make and mesure the larvae. 2kg/5lb of white flour along with 1kg/2lb of lard were the main components of the larvae, in addition to quinine sulfate and food colorig.

The larvae were placed into little plastic petri dishes by the specific intructions laid out by the arrays. The feeing array charts were arranged on the waterproof paper and marked with marking pens. Disposable gloves, wax paper, and masking tape assisted the making process of making the food easier. A refrigerator was utalized for the storage of prepared petri dishes with larvae. The chi-sqare analysis and graphs, will help analyze how many larvae were removed or remained at the end of each deployment/retrieval period.

Results The results of this kind of experiment are typically used to either prove a null hypothesis (H) or approve an alternative hypothesis (H). The chi-square analysis is an effective means to prove or disprove hypothesis. The total # of prey removed for day 1 was 3. The # of red larvae deployed was 64. The observed removed from the red larvae was 2.

The expected removed was 64*3/200 =.96. This was calculated frm taking the total amount deployed times the total amount of larvae that was observed as being removed, divided by the total amount of larvae deployed in that day. THe chi-square analysis for the red larvaewas (2-.96)^2/.96 = 1.1. For day one, the blue larvae deployed was 70., while the observed removed was 0. The expected removed was 70*3/200=1.05.

The chi-square analysis for the blue was(0-1.05)^2/1.05= .0024. For day one, the lime larvae was 66, while the observed removed was 0. THe expected removed was 66*3/200= .99. The chi-square analysis for the green larvae was (0-.99)^2/.99=.99. In order to find the chi-square analysis for the total # of prey by color (combining AM and PM data) on day #1, you would simply add up all the chi-square numbers calculated and compare it to the (x^2 0.05, 2=5.991 …