Experimental Design. The Mass Gain Found in Monarchs Subject to Four Different Food Sources

Transcription

1 Experimental Design The Mass Gain Found in Monarchs Subject to Four Different Food Sources October 30th, 2008 EDU-246 Professor Michele Koomen Experimenters: Molly Mathiowetz Cassandra Brady Lena Miller

2 Abstract To start off, we separated sixteen monarchs into four cages, with four monarchs (two females/two males) respectively in each cage. Then, over the course of the next sixteen days we fed the monarchs every two days with the cage s specified food source. The first cage of four monarchs was fed a 100% grape juicy juice solution, the second a 100% white grape juicy juice solution, the third cage was subject to the New England Aster flower, and the fourth cage of monarchs was fed a honey water solution of 80% water/20% pure honey. The liquid food sources were manually fed to the monarchs every second night by one of us experimenters through the Petri-dish system. The monarchs in the flower cage had access to the New England Aster flowers everyday, all day long, to ensure the monarchs had enough time to nectar. The way we collected our data was to weigh the monarchs every morning in little envelops on an electric balance. The balance massed out the monarchs in grams. The reason we massed the monarchs on a daily basis was to see what food source led to the greatest mass gain in the monarchs. Another step we took in gathering data was to make daily observations (See Appendage A) of the monarchs two times a day, one time in the morning and another in the evening, to see what kind of activity the monarchs participated in at different times of the day. We wanted to see if there would be any indications of how the monarchs were reacting to the food source, whether this be a positive or negative reaction, that would essentially backup the massing data we would collect from the monarchs. The purpose of this experiment was to see whether or not the type of food source the monarchs were subject to affected the average mass gain of the monarchs, no matter the sex. After struggling to keep our sample size constant, due to unforeseen deaths and illness, we only managed to

3 get seven days of usable data with a total sample size of sixteen monarchs. Over the course of these seven days, the results suggested that the greatest mass gain of the monarchs occurred first in cage two then in cage three, cage four, and finally cage five. Based off of the fact that this data was gathered over the course of seven days makes our results inconclusive due to the small sampling and testing size. When we further evaluated our findings over the entire duration of our experiment, which was sixteen days, we randomly selected two monarchs(f1 s and M1 s) per cage to find the average mass per cage. This created a sample size of two monarchs per cage, which was the only way our data could be collected due to multiple deaths in the monarchs after day seven of our experiment. The way we randomly selected two monarchs in each cage was to take the first male and female in each cage. These results pointed to cage one having the most mass gain, then cage four, and finally cage two. After seven days, we were forced to discontinue the research of the monarchs in the third cage, because the monarchs got severely ill. As a result, we collected no data from the third cage after day seven of our experiment. Through this experiment, we realized how hard it is to keep monarchs alive and happy outside of their natural environment. The room in Mattson Hall in which we kept the monarch cages was very dry and hard on the monarchs bodies due to the ventilation system in the building. We also learned how unforeseen death and illness can change the direction of one s experimental data in a flash, as was seen when we were forced to discontinue the natural food source cage where the monarchs were being fed New England Aster flowers. Introduction After having raised monarchs from the stage of an egg to an adult monarch

4 butterfly, we felt the urge to continue experimenting with the monarch butterfly to learn more about the last stage all of our larva would live out. The eating habits of the monarch butterflies really intrigued us, because some of us remembered having butterflies in the classroom when we were younger and feeding them with juicy juice. We also realized that our professor, Michele Koomen, preferred a honey water solution of 80% water/ 20% honey to feed her research monarchs. Through this same class, we were given power point information about the food that monarchs find nutrients from, and started to inquire what type of food sources monarchs have preferences towards. The information in this packet was from a website called Monarch Lab, Monarchs in the Classroom a program from the University of Minnesota. We found out that they can eat the nectar from a flower, a honey liquid solution, and even certain fruits from research on the internet, talking to Professor Koomen, and through past science teachers that had monarchs as part of our elementary educational units. We also looked on the web, and found out from numerous sources that people feed their monarchs juicy juice such as: Another one of the sources we used was Monarch Watch, a website that is dedicated to providing information about monarchs. We also found an experiment on the internet that had been done by Robert Richardson of Richardson Academy of Avon, Indiana. In this experiment he tested to see if monarch butterflies would have a larger

5 mass if they ate sugar water or a variety fruit. Another experiment that we found was done by Gustavus students a couple of years ago that tested to see if monarchs had a preference between honeydew melon and cantaloupe melon. After having looked at all of these experiments and websites, we decided that we wanted to see if monarch butterflies were healthier ( as measured by mass) if they ate from the nectar of a flower, a honey water solution of 80% water/ 20% honey, grape juicy Juice, or white grape juicy Juice. The following is our hypothesis for our experiment: HA1: The monarchs show the greatest mass gain from feeding off the natural nectar from the flowers food source. HA2: The monarchs show the greatest mass gain from feeding off the grape flavored juicy juice. HA3: The monarchs show the greatest mass gain from feeding off the white grape juicy juice. HA4: The monarchs show the greatest mass gain from feeding off the honey water solution. H0: There is no difference in the mass of the monarchs when subjected to different food sources. Design and Methodology Materials -4 butterfly cages -16 monarch butterflies -butterfly envelope -electronic scale (in grams)

6 -spray bottle containing water (to mist monarchs) -honey water solution (80% water, 20% honey) -white grape juicy juice (100% juice) -grape juicy juice (100% juice) -black-eyed Susan flowers (from Gustavus Arb) -Petri dishes (for feeding) -Plastic containers to place over the monarchs while they feed We used 16 butterflies in our experiment, 8 males and 8 females. We split them up into 4 cages. There were 2 males and 2 females in each cage. The cages were stored in Mattson Hall in the Curriculum lab. We observed the monarchs in the morning and evening at 8:00am and 8:00pm respectively. We all observed the butterflies the same way, by following an observation rubric (see appendix A). We noted which butterflies were on the top and bottom of the cage, where they were located in terms of the other butterflies in the cage, and any sort of movement they were making. Each morning the butterflies were massed. Each butterfly was taken out of its cage, on at a time, put in a special butterfly envelope, and placed on the scale to find its mass. The mass was then recorded on a sheet of paper. We kept track of the butterflies by marking the butterflies with a certain number of spots on their wings by using a fine, blacked tipped permanent marker. In each cage, the monarchs were fed a different type of food source. In cage 1 the butterflies were fed grape juicy juice, in cage 2 they were fed white grape juicy juice, in cage 3 they were fed Black-Eyed Susan s, and cage 4 was fed a honey water mixture of 20% honey and 80% water. When feeding the monarchs, we made sure to do it the same way every time. The solution was poured about half way into a Petri dish, and then

7 the monarchs were able to drink out of the dish using their proboscis. (Note: if the monarchs did not put out his/her proboscis to eat on his/her own, the experimenter used a paper clip to assist in the unfolding of the proboscis.) The four monarchs were placed by the solution were they were allowed to eat until they were finished. The monarchs notified the experimenter that they were finished by moving around in the cage and flapping their wings. A container was put over each monarch while it was feeding so that it could not fly away. The fourth cage s food source was assessable at all times to the monarchs, to ensure the monarchs had enough nectaring time with the flowers. The monarchs in each cage were fed the same solution or flowers the entire length of the experiment with the exception of the butterflies that were fed the flowers. These butterflies started to die due to lack of abundant fresh flowers. So, after day seven we were forced to discontinue the natural food source (New England Aster), and had to feed the monarchs in this cage the honey water solution to try and get the monarchs back up to health. While conducting our experiment we maintained control of the temperature and light and dark variables by keeping the monarchs in the same room environment in Mattson Hall: the Curriculum lab. By putting all of the cages in the same room next to each other, the monarchs in each cage were subject to the same weather, temperature, and light verse dark variables. We made our monarch observations at the same time each day: 8:00 a.m. and 8:00 p.m., to ensure that we observed the monarchs habits consistently. Another control factor was feeding all the monarchs at the same time, with the exception of the New England Aster flower cage. In general, the sample size of the monarchs per cage, number of cages we kept the monarchs in, and the ratio 2:2 of male

8 and female monarchs in each cage all had to be kept constant. When looking at how the data was collected, each monarch was weighed individually in the same butterfly envelope on the same electronic balance ensuring that there would be a consistency in the net mass gain or loss in each monarch over the course of the experiment. This made the different food sources that we fed the monarchs the independent variable of the experiment, and the weight/mass gain of each monarch the dependent variable of our study. Procedure for observing: - at 8:00am and 8:00pm we wrote down the following - which butterflies were on the top and bottom of the cage -where they were located in terms of the other butterflies in the cage - any sort of movement they were making and the way their wings were positioned Procedure for massing the butterflies - the butterflies were massed in the morning - each butterfly was taken out of its cage, and put in an envelope - they were placed on the scale to find its mass - mass was recorded on a sheet of paper *We kept track of the butterflies by marking the butterflies with a certain number of spots on their wings. Procedure for feeding the butterflies * In each cage the 4 butterflies were fed a different type of food grape juicy juice, white grape juicy juice, Black Eyed Susan s, and honey water mixture of 20% honey and 80% water.

9 - solution was poured about half way into the Petri dish - four monarchs from specified cages were placed by the solution to eat - container was put over each monarch while it was feeding so that it could not fly away *The butterflies that were eating the flowers had the flowers in their cage the whole time and were given fresh flowers every other day. Results: * Refer to the Appendix A. Observation Guidelines B. Table Including Daily Mass and Observations C. Bar Graph Showing Average Mass Gain of Cages (Days 1-7) D. Bar Graph Showing Average Mass Gain of Cages (Days 1-16) E. Scatter Plot Showing Average Mass Gain of Monarchs (Days 1-7) F. Scatter Plot Showing Average Mass Gain in Monarchs (Days 1-16) Interpretation and Discussion: After computing the values needed for the t-test from our collected data, we came to the conclusion that the t-test cannot be applied to our experiment. When looking deeper into the meaning of the t-test, we discovered that the core comparison being done with the t-test has to deal with the comparison of the responses of two groups. The two groups were to come form different populations, and the results of the dependent variable had to be continuous. True enough, the results we got from our dependent variable (mass of the monarch) was continuous, the mass of a monarch is such a small value and undergoes such small changes in mass that it is hard to show these changes with confidence. As a result, when we computed our t-test results, we got answers that

10 were many powers off from being able to be applied to the degrees of freedom in the critical values chart of t. When looking at our own learning through the Nature of Science principles, we discovered that this was the first real experience we had in designing, conducting, collecting data, making hypothesis s, summarizing our findings, and making a conclusion. Through this experiment, we had to do past research to discover what other scientists, teachers, and monarch admirers thought was the best way to rear the critters, and, as a result, we had to be open to other s ideas in caring for the monarchs and their well-being. The research we collected through different sources was created by a variety of different people with different educational backgrounds. This gave us confidence to pursue with our experiment, for we believed we could scientifically conduct this experiment and find some interesting findings just like other scientist did before us. Also, through the observations we made throughout our experiment we got a chance to include interdisciplinary learning, for we had to use a lot of detail and creative verbs to describe the monarch behaviors. These are all great aspects that the Nature of Science principles points out should be accomplished through students in their education. As a future teacher, having this experience in creating and completing an experiment will give us confidence to do similar tasks with our own students. By not being afraid of allowing our kids to learn science hands-on, the students will get a better picture of what it means to experience science on a fun and interesting level. It will be a better experience for the teacher and students if learning science was based on the realworld, verse demanding the students understand tough topics and theories from a textbook with few pictures. By allowing students to plan their own experiments, they can

11 pick a topic of their choice, and learn a step by step process that can and will be used in many other classes to organize and express their findings. Implications and future work: This experiment was conducted in hopes of finding what food source would lead to the most mass gain in monarchs. We found that our experiment results over the course of the first seven days of our experiment suggest that the greatest mass gain of the monarchs occurred first in cage two, then in cage three, cage four, and finally cage five. Based off of the fact that this data was gathered over the course of seven days makes our results inconclusive due to the small sampling and testing size. When we further evaluated our findings over the entire duration of our experiment, which was sixteen days, we randomly selected two monarchs (F1 s and M1 s) per cage to find the average mass per cage. This created a sample size of two monarchs per cage, which was the only way our data could be collected due to multiple deaths in the monarchs after day seven of our experiment. The way we randomly selected two monarchs in each cage was to take the first male and female in each cage. These results pointed to cage one having the most mass gain, then cage four, and finally cage two. After seven days, we were forced to discontinue the research of the monarchs in the third cage, because the monarchs got severely ill. As a result, we collected no data from the third cage after day seven of our experiment. The difference in these results surprised us, and would be great to look into further. To do this, perhaps a longer study of four to six weeks would help strengthen this finding. Also, a larger population of butterflies would significantly help reinforce the results as well. We started out with 16 butterflies and ended with 10 butterflies. If we had a larger population, we would be able to be more confident in our result. Another factor

12 that needs to be considered is doing the experiment at a time where there are multiple types of flowers available for the monarchs to nectar on. This would allow us to compare the results with the results of the juices and honey on a more accurate terms. It would also be interesting to use more than one flower and other types of juices. The environment should also be a factor that should be changed. The building that the monarchs were placed in had low humidity and lots of sunlight. We believe that the environment of the experiment may have affected the results of the experiment, and therefore think that for future tests, the monarchs should be set up as close to their natural habitat as possible. Overall, we think the timing of our experiment could have been better, not only would a different time have helped with the flower source, but it would have included a different generation of monarchs. It just so happened that the monarchs we received from Professor Koomen was the migrating generation. These monarchs are programmed to head to Mexico for the winter, and, as a result, have a different life-span than other generations of monarchs. We feel that the other generations of monarchs might have given us different results. This idea could lead to the formation of a similar experiment based on the idea of whether or not the migrating generation of monarchs has different eating habits or preferences than that of the neighboring generations. Limitations: Whenever an experiment is being conducted, many limitations can occur. It is a normal process that should be recognized in every experiment. The limitations of our experiment included sampling size, consistency of getting data, the environment that our experiment was done in, and the season it was being conducted in.

13 By using the resources made available to us through Professor Koomen, we were able to obtain 16 monarch butterflies for our experiment, which was very helpful, but not quite enough to gather accurate data over a period of time. In order to get a more accurate result, a larger population of monarch butterflies should be studied. Due to the small sampling size, we only ended up getting complete data from all sixteen monarchs over the course of seven days. After this, we were forced to only collect data from two monarchs per cage, while eliminating the third cage completely. This, unfortunately, decreased our sample size even more. The environment was also another issue. At the beginning of the experiment, we had the butterflies in the curriculum lab of Mattson Hall on top of some book shelves. This room had lots of sunlight, and also had dry humidity. We believe these dry conditions had a negative affect on the monarchs, which led to unforeseen death and illness. When we started our experiment, it was the beginning of fall. By this point, most of the flowers that the butterflies nectar on were either dried out, scarce, or non-existent. However, we were able to find some Black Eyed-Susans for one of our cages. The only problem with this was that it wasn t fresh enough for the butterflies to get enough nutrients from it. As a result, the monarchs died, possibly due to this reason. This issue caused the results of the experiment to change significantly, because we were expecting to get more results on this cage, in order to compare these results with the other food sources. In conclusion, our experiment had many general limitations such as sample size, time, unforeseen death and illness, and limited data collection, still we did see some

14 changes between the average mass gain in the monarchs in each cage. The problem with these results is that the numbers are so small scale, that we cannot have much confidence in our findings as we mentioned with our inability to use the t-test earlier on in the paper. Conclusion: By creating and conducting the experiment, The Mass Gain Found in Monarchs Subject to Four Different Food Sources, we used an electronic balance to mass out the sixteen monarchs over the course of sixteen days, and concluded that our findings were not significant enough to allow us to confidently suggest that one of the four food sources: grape juicy juice, white grape juicy juice, honey water solution 80% water/20% honey, New England Aster flower, were responsible for the net mass gain or loss in the monarchs. We did, however, learn as experimenters what it means to be able to design, conduct, gather data, and make conclusions based off the experiment findings. Acknowledgements: We must thank professor Michele Koomen for guiding us through this experiment. Without her help, we would not have had most of the supplies or ideas to get the experiment going.

15 References: Cohen, L. (August 9, 2003). School project takes flight: Pleasantville 4th-graders release monarch butterflies raised from eggs. PressofAtlanticCity.com, Retrieved October 19, 2008, from Harris, J. (2006). Monarch s Preference of Honey Water. Retrieved October 19, 2008, from Monarch lab: Monarchs in the classroom Web site: King, C. 'Plant more milkweed,' Monarch butterfly lovers urge. The Sylva Herald, Retrieved October 19, 2008, from Koomen, M. (2008). EDU 246: Science for Elementary educators fall 2008 course packet. October 19, Monarch Watch, (2007). What to feed monarchs?. Retrieved October 19, 2008, from MonarchWatch.org Web site: On my honor, I pledge that I have not given, received, or tolerated others use of unauthorized aid in completing this work. Molly Mathiowetz Cassandra Brady Lena Miller mmathiow@gustavus.edu cbrady@gustavus.edu lmiller@gustavus.edu

16 Appendix A Date: Time: Experimenter Name: Observations 1. What half of the cage are the monarchs on? Top _ or Bottom _? Cage One: Cage Two: Cage Three: Cage Four: 2. Are there any monarch groupings? What gender is each monarch? Is there male/female groups, female/female, Etc.? Cage One: Cage Two: Cage Three: Cage Four: 3. What is each monarch doing? Is the monarch still, flapping its wings, flying, walking, mating? Is the monarch stationary? Cage One: M1: M2: F1: F2: Cage Two: M1: M2: F1: F2:

17 Cage Three: M1: M2: F1: F2: Cage Four: M1: M2: F1: F2: 4. Are there any additional comments about the monarchs color, behavior, and or energy level displayed? Are there any monarchs looking sick? Is there a cage of monarchs showing more energy than all the others? Etc.

18 Appendix B Couldn t get it to paste on this word document. Handed in as a paper document spreadsheet.

19 Appendix C

20 Appendix D Appendix E

21 Appendix F

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