orientation movements of Narceus americanus when presented a strawberry stimulus Michael Donkor, Jamar Hurtt, Gissel Cuestas, Rachael Adeoye Regional Math/Science Center, Frostburg State University, Frostburg, MD 21532 Methods Introduction • A 11" x 17" box was used and the grid was separated into a 5 x 7 matrix Discussion with marker. Millipedes are Arthropods, which are the largest phylum of Our data supported our null hypothesis. Since the p-values for • A decaying strawberry was placed on number 1 of the gridded box the animal kingdom. They are scientifically known as the class the decaying strawberry (0.015821) and the fresh strawberry (see figure 2). Diplopods. Millipedes are worm-like animals made up of multiple (0.000699) are less than the alpha value of 0.05, there is a body segments. They have two pairs of legs attached to each • One millipede was lightly poked at so it could be awoken for the significantly higher number of non-directed movements made by segment and most millipedes have usually have 50-375 experiment and was then placed on the numbers 18 and 19 and covered millipedes in the presence of both decaying and fresh strawberries. legs. The millipedes we are studying are the North American with a small container until the timer started. Non-directed movements are considered to be a kinesis, so the millipede (Narceus americanus). The North American millipede • Grid paper was used to replicate the box grid so we could record the millipedes used kinesis behavior towards the decaying and fresh can be found in the United States in all states east of the orientation movements of the millipede for five minutes. The orientation strawberry. There is no difference in the orientation behaviors Mississippi river and nine states to the west (Millican, 2013). movements were based on each sharp turn that the millipede made. between the strawberry types; there our null hypothesis can be They are mainly black and have a range of colors on the edges • Two different colors were used to differentiate between directed accepted. of their body segments. North American millipedes average a movement and non-directed movement of the millipedes on the grid paper. Our results were supported by information sources, in an article mass of 2.5 g and a length of 10.2 cm. Most North American • The procedure was repeated 19 times with a decaying strawberry and we read, it stated that at the base of a millipede's antennae there are millipedes are found in forests and agricultural areas, in spaces 20 times with a fresh strawberry; each trial was repeated with a different Tömösváry organs, which can measure a multitude of things. These like dead trees, and piles of moist dead leaves. They are millipede. organs also act as chemoreceptors, which allows them to sense confided to habitats of high moisture because they become • A t-test with 95% confidence intervals was performed to compare their environment's, taste food, smell odors, feel, measure dehydrated quickly. North American millipedes feed on decaying the difference between kinesis and taxis movements in the presence temperature, find water, and sense pheromones (Millican, matter, such decaying leaves, wood, roots and plants. They also of fresh or decaying matter. 2013) since their antennae are not infinitely long, they can only eat their own feces, which helps them digest nutrients that may sense their close surroundings; therefore, having to roam around or not have been digested the first time. All millipedes breathe make kinesis movements until they get to a food stimulus. through spiracles, which are connected to their tracheal If I were to repeat this experiment I would make the boxes respiratory system (Millican, 2013). When threatened, millipedes replicate the kind of habitat that millipedes prefer so that we could produce a chemical that deter potential threats. see how their orientation movements change when they are in a familiar or comfortable environment. This might make the Orientation behaviors are coordinated movements that occur experiment we already have more convincing, because then we in response to an external stimulus. They are seen as innate know that the cold box that they are not familiar with and the behaviors because they are developmentally and genetically shadows it cast would not be an extra variable that would cause fixed. Taxis and kinesis are orientation behaviors. Kinesis is a them to perform more taxis or kinesis movements towards or away change in the speed movements that occur in response to an Figure 2. A decaying or fresh strawberry was from an additional stimulus. Figure 1. Narceus americanus (North Sources of error that occurred in our experiment were that they external stimulus. Taxis is a movement directly toward (positive) American millipede) placed in box number 1 or away from (negative) a stimulus. (Meyer, 2009). For example, kept on trying to crawl out of box, and that we did not have consistency, because some trials we used saran warp to cover the if there is a flashlight pointed at a millipede and it directly moves 6 away from it that would be a negative taxis. Since we can box and other trials we didn’t. Something I would like to study in the observe this behavior by watching the millipede, it would also be 5 future is what temperature millipedes are most comfortable in. I could test that by putting them in different temperatures and seeing if considered overt behavior. 4 there is a change in the way they behave. 3 2 1 AVERAGE #OF MOVEMENTS AVERAGE 0 References Decaying Fresh Meyer, J.R .(2009). Elements of Behavior. General Entomology. Objectives TYPE OF STRAWBERRY Retrieved from https://genent.cals.ncsu.edu/bug- Direct Non-Direct • Purpose: To see how the type of orientation behaviors of bytes/elements-of-behavior/ Narceus americanus compare when in the presence of fresh Figure 3. Comparing directed or non-directed movements or decaying matter. toward decaying or fresh strawberry, 95% confidence Millican, K .(2013). Narceus americanus. AnimalDiversity. Retrieved • Importance: While gaining background information on intervals are shown with the error bars from http://animaldiversity.org/accounts/Narceus Narceus americanus, we found that decaying matter _america nus/ containing bacteria and fungi increases the availability of nutrients for a millipede. We already know that this affects Results Averages of movements of Narceus americanus in the presence of a decaying strawberry: their food preference so we wanted to find if it would affect • their orientation behaviors as well. • Directed movements = 1.85 • Null Hypothesis: There is no difference in the type of • Non directed movements = 4.3 • Averages of movements of Narceus americanus in the presence of a fresh strawberry: Acknowledgements orientation behavior made by Narceus americanus in the We would like to give a special thanks to Frostburg State Directed movements = 1.25 presence of a decaying or fresh strawberry. • University for letting us use their facility to conduct our research. • Alternative Hypothesis: There is no difference in the type of • Non directed movements = 4.15 We would also like to thank the administrative staff Rita Hegman, orientation behavior made by Narceus americanus in the • P values from T-test used with 95% confidence intervals: Angie Ferguson, and Kayla Precourt, and our tutor counselors, presence of a decaying or fresh strawberry. • Taxis vs kinesis for decaying - 0.015821 Sydney Greer, Molly McEvoy, Daniel Jones, and Brady Barnhart • Taxis vs kinesis for fresh - 0.000699 Comparison of Direct and Non-Direct Movements of N. americanus By a Decaying and Fresh Strawberry Regional Math/Science Center, Frostburg State University, Frostburg, MD 21532 Introduction Methods Discussion Narceus americanus are crustacean-like invertebrate • A 11" by 17" cardboard box was built with a 5 x 7 matrix of We are able to accept the null hypothesis, organisms classified as arthropods, which is the biggest phylum in the boxes. The squares of the matrix were labeled with numbers 1- because there was no difference in the type of behavior shown by the animal kingdom (Benson, 1999). Members of the phylum, such as 35. millipedes in the presence of either stimuli. After doing the statistical t- millipedes, are segmented organisms that have jointed limbs and an • A decaying strawberry was placed on square 1. A millipede was test, we were able to compare the alpha value of 0.05, with a p-value of exoskeleton made of chitin. One of the most important characteristic of placed on square 18, after being woken up, and the timer was .015821 for the decaying strawberry data and another p-value of the millipede is their exoskeleton (Benson et al, 1999). Millipedes prefer started for five minutes. 0.000699 for the fresh data set. Since both p-values were smaller than moist, dark environments, such as mulchy, soiled areas. There are • The movement of the millipede was traced on a separate sheet 0.05, we were able to say that kinesis was the majority movement for spiracles under their exoskeleton which are next to their joints, to help of grid paper, which was a replica of the box's matrix. both data sets; so, between each set there was no difference in the the millipedes breathe; also, these holes connect to their tracheal • The directed movements (towards the stimulus) and the non- movement type. Due to this conclusion, we were unable to accept the respiratory system. With living in such moist, dark conditions, the directed movements (away from the stimulus) of the alternative hypothesis, which was: "There is a difference in the type of millipede prefers to eat decaying organic matter. Millipedes are millipede were highlighted in two different colors and counted. A orientation behavior made by Narceus americanus in the presence of a decomposers, which means everything they eat is returned to the soil for similar procedure was followed with a fresh strawberry.