Biology 342 Fall 2012
In teams of two or more (up to four), students conducted an independent research project for the second half of the semester. The projects were based on ideas generated during the planned labs. They were open to explore any area of animal behavior using techniques that are available at Reed College. Projects were presented at a formal poster presentation session attended by all students during finals week. (see the end of this page for assignment details)
Not All It's Quacked Up to Be: Mallard Ducks and the Motivation-Structural Reule Hypothesis
Harvesting Heat: The effect of Capsaicin in Pogonomyrmex barbatus Coloines as a Tunneling Mechanism Inhibitor
A Good, Clean Fight: Effects of Laundry Detergent Ingredient 4-nonylphenol on Agonistic Behavior in Crayfish
Cray-Crayfish: Increased Acidity and Predatory Response
Don't Use That Tone With Me!
Would you like some lithium chloride with that?: An Attempt at Cricket Food Aversion.
The Biological Link Between Time and Space
Guppy DUIs (Decisions Under the Influence of Stress)
GABA-(A) neuroreceptors have been found to be upregulated in dominant male Astatotilapia burtoni cichlids, but their role in the regulation of social behavior is not completely understood. To investigate the importance of GABA-(A) receptors to the maintenance of social hierarchies, we suppressed their activity in dominant male cichlids. Six male pairs were observed by continuous focal sampling, and behavior scores were calculated to establish dominance hierarchies. Dominant males were injected with the GABA-(A) antagonist (+)-Bicuculline and returned to their original pairing. Social behavior was observed three hours post-injection and new dominance scores were calculated. Due to a large loss of test subjects, the results of this study are inconclusive. However, comparison of dominance scores from the remaining experimental group pre-and post-injection suggest that the inhibition of GABA-(A) receptors decreases aggressive behaviors. Further research is needed to confirm the active role of GABA-(A) in regulating social behavior of cichlids. (top)
The motivation-structural rule hypothesis (MS rule) states that aggressive vocalizations are low-frequency and high bandwidth, while fearful or friendly vocalizations tend to be high frequency and tonal (Morton 1977). The MS rule has been applied to multiple taxa (August 1987, Gouzoules and Gouzoules 1999, Compton et al. 2001), but not yet to mallard ducks (Anas platyrhynchos), a widespread and easily-observed waterfowl. We attempted to test whether the MS rule can be applied to mallards by using a shotgun microphone to obtain digital audio recordings of mallard vocalizations in aggressive and non-aggressive contexts and then characterizing the recordings using Raven Lite bioacoustics software. While a small sample size prevents us from claiming statistical significance, our data suggest the MS rule does not apply to mallards, as both aggressive and non-aggressive vocalizations share similar frequencies and bandwidths, primarily differing in amplitude. This result may support an alternative hypothesis that the volume, rather than the frequency, is correlated with aggression. (top)
Prior literature has shown that circadian rhythm of an organism is directly involved in the prediction and recognition behaviors that that organism exhibits in response to repetitive events. This indicates that placing a fish on an extended light-dark cycle might interact negatively with the natural feeding cycle of the fish. However regulating the feeding of the fish acts as an exogenous cue to potentially override the effect of the extended circadian rhythm, defined as an increase in typical pre-feeding activity during the behavioral assay. Two sample groups of white clouds (n=20) were put on a 28 hour cycle with a single control group (n=20) on a regular 24 cycle. After a ten day acclimation period, increases in activity were assessed during the four hours leading up to feeding. (top)
Few behaviors know to biology are as prevalent-- yet so able to elude definition and adaptive explanation -- as play. Only a modest amount of research has been published regarding play since Robert Fagen’s 1981 review of the phylogenetic distribution of play. Hypothesized functions of play include refinement of skills, especially combat skills (Fagaen 1981; Caro 1988)]; the “getting into shape” hypothesis, that proposes that the function of play is exercise (Bekoff & Byers 1998). Regarding the evolution of play, recent studies across animal phyla, such as Burghardt’s observations of turtles engaging in object play, have turned previously accepted ideas about play being an exclusively mammalian trait have been turned on their head. As Byers and Bekoff commented, the small amount of observational data available has limited hypothesizing about the evolution and function of play. Aiming to contribute to filling in knowledge gaps concerning differences in the nature of play based on trophic strategies and the social behaviors of animals, we observed behavior of Asian elephants (Elephas maximus) and caracals Caracal caracal at the Oregon zoo. Focal sampling revealed that though both species engaged in social play, the time budget of the caracals favored hunting and combat related behaviors than the elephants. (top)
The purpose of our experiment was to observe the ways in which cayenne powder, containing capsaicin molecule C18H27NO3 affects behavior in ants, specifically their ability to construct tunnels, in order to find targeted insect mechanisms to control and then aid in garden pest control. The experiment had two parts: in the first, 3 ants farms were constructed containing 0%, 10% and 20% cayenne powder by mass in the sand. At the same time, ants were placed individually in Petri dishes with 0%, 5%, 10% and 20% cayenne powder by mass in sand. After 200 Petri dish trials, a Tukey-Kramer HSD comparison of means was done and it was proved statistically significant that ants in dishes with higher levels of cayenne attempted to climb out to the dish with greater frequency than ants in dishes with low levels of cayenne. This supplemented the observations from the ant farms in which only ants in the farm containing 0% cayenne in the sand did any tunneling at all. The study is relevant because it proves that cayenne, probably due to capsaicin (which, according to background research is shown to reduce thermoregulation in insects) agitates the ants enough to cause them to avoid tunneling. (top)
Detergent metabolites like 4-nonylphenol, as well as pharmaceuticals, hormones, and antibiotics, are found in worrying concentrations throughout the nation’s waterways on a regular basis, and detrimentally affect associated ecosystems (Kolpin, et al. 2002). Organisms like crayfish have chemically-mediated communication systems that warn of injured conspecifics or predators; damage to these and other physiological systems by pollutants can have profound effects on behavior, and indicate the quality of water in a given environment. Agonistic behavior in crayfish (Orconectes rusticus and Procambarus clarkii) was compared before and after treatment to gauge the toxicity of two environmentally-relevant concentrations of 4-nonylphenol: 40 μg/L and 0.8 μg/L (Kolpin, et al. 2002). Animals were numbered, and then paired and divided randomly between treatments or control with a random number generator. Each pair consisted of either a treated or a control crayfish versus a control, and were allowed to interact for a fifteen-minute observation period in a five-gallon, clear plastic tank to establish a dominant and submissive and to determine the latency to aggression of the dominant (Cook, M. and Moore, P. 2007). Crayfish were then separated into treatment or control tanks and exposed for six hours to mimic a runoff event, after which they were allowed to interact a second time, with latency to aggression recorded again. Possibly due to small sample size (each treatment group had N=4, and control had N=16) and errors in execution and design, no significant differences between the means of pre- and post-treatment latencies to aggression were detected with a Wilcoxon matched pairs test. Results suggest that the maximum and median concentrations of 4-nonylphenol found in Kolpin, et al. are not harmful enough to alter agonistic behavior, but further research is required. (top)
Serotonin has been shown to play a role in animal aggression. In fish, specifically, exposure to serotonin has been implicated in lowered levels of aggression in dominant males and the reverse in subordinate males (Le Page 2005, Munro 1986, Perreault 2003). We hypothesized that dominant A. burtoni males injected with serotonin would display reduced levels of aggression. To condition dominance, focus males were each housed for 23 days with two females and one smaller male before being paired by weight. One individual was injected with 0.25 M serotonin in saline (aprox. 3 μL / g), the other with saline. After an acclimation period, aggressive interactions between the two individuals were observed and tallied. Due to small sample size (n =2) and difficulties in inducing agonistic behavior, the data gathered was not sufficient to show any significant effects. However, qualitatively serotonin-treated individuals were observed to be particularly lethargic, which would preclude aggressive behavior. These results are promising, but more extensive experimentation is necessary to answer this question definitively. (top)
Pigment dispersing factor, neuropeptide that controls Drosophila melanogaster locomotion and behavioral rhythmicity on a circadian timescale. Is is expressed in a manner determined by PER nuclear translocation. While PDF mutants have been employed to examine the relationship between PER gene expression and PDF release in lateral and central neurons, no studies have use PER mutants and wild type flies to examine potentially existing reverse relationship. I microdissected the brains of PER short (21 hr cycle) and PER wild type (24 hr cycle) Drosophila melanogaster (N=9 for each group) at a time point just prior to lights on. These brains were labeled rabbit anti-PDF at 1:1000 dilution and counterstained with Goat Anti-rabbit IgG conjugated to Alexa 488 at 1:600 dilution. The label was visualized on a Leica epiflourescent microscope. Because of the short time period in which I learned microdissections, only one brain showed differential expression of PDF. Further studies should allow sufficient time to train microscopy skills and dissection skills so that the hypothesis, that PER short mutants display less PDF expression at the time of shift in their cycles than PER wild type flies, can be tested. Counterstaining with DAPI to locate all cell nuclei in the brain could be of some assistance if glia/astrocytes and neural tissue were to be compared for PDF expression levels. (top)
Use the Project Management Template to plan your indpendent project. Where a grant proposal emphasizes the strengths and feasibility of a project, putting the best spin on everything, a project management plan is meant to help identify potential difficulties before they arrise. While not required for the assignment, you may also find it helpful to construct a timeline of work to be done (in project management speak this is called a Ghant Chart)
Dec 9th :: Abstracts due
An abstract (~250 word) with a descriptive (fun) title and the authors names.