Lab : Habitat Shifts by Snails in Response to Predator Cues
Title
The title identifies the important components of the paper and orients the reader by specifying the writer’s major findings or perspective. A good title is important if you want your paper to be read by others. For example, abstracting and indexing services rely heavily on titles for categorization purposes. Other scientists will use your title to determine if they want to obtain and read the paper or not. An inaccurate title may waste a reader’s time by suggesting, erroneously, that a paper contains certain information.
Organize your title around important words (keywords) of the study (e.g., antipredator behavior, snails, molluscivorous fish). You want to ensure that your paper is noticed by readers interested in this subject. Therefore, avoid being too vague in your title, but also be concise.
Abstract
The abstract is a short (approximately 250 word) passage that summarizes all major elements of the paper: introduction (including objectives), methods, results, and discussion (including major conclusions). It usually consists of a single paragraph, and a good abstract will stand on its own. In other words, readers should be able to understand what was done without having to refer to other sections of the paper. Several revisions are usually required to get an abstract into satisfactory shape. Be concise, but not too vague, so that readers can better decide if they want to read the paper. In most cases, this is the only section of your paper that readers will read. References are not cited in the abstract text.
Introduction
The introduction is where you present your argument for why the study was done. It places your work in a broad conceptual context and gives readers enough information to appreciate your objectives.
Proceed from the general to the specific, starting with a brief review of current knowledge of the topic and gradually narrowing to the specific question(s) you have addressed. For example: you could begin with “Interactions among predators and prey are important in structuring communities”, and end with, “Our specific objectives were to determine if physid snails detect predators through chemical cues, and subsequently move to habitats that provide refuges from these predators”. The introduction usually concludes with your specific research question, objectives, and/or hypotheses.
It is critical that you document (cite) key references in this and all succeeding sections of the paper. References used should be from the primary literature (e.g., peer-reviewed scientific journals). Proper citation format in the text sections of the paper (including the introduction, methods, results, discussion) consists of listing the author(s) followed by the date of publication (e.g., Brown and Jones 1998). If there are more than two authors for an article, list the first author followed by “et al.” (e.g., Brown et al. 1999).
Methods
The key point here is to include enough information so that your study could be repeated. This is also necessary so that the quality of the data can be assessed. Tell the reader where the study was conducted (do this first), then describe sampling devices, procedures, statistical analysis techniques used, etc. It is important to organize this section of the paper well. Subheadings may help in this regard. Include only those procedures directly pertaining to the results you plan to present and discuss later (e.g., you don’t need to say that your instructor went to the store, purchased aquaria, etc.).
Results
The results section should summarize important data and statistics graphically and narratively so that interpretations and conclusions you will make in the discussion section of the paper are supported. Use figures and/or tables to summarize data, number figures and tables in the order they are presented, and cite figures and tables as (Fig. 1) or (Table 1) in the text. For example, means and variance measures could be summarized using bar charts (a figure). Key results from statistical analyses must also be provided (e.g., t statistics, critical t values, degrees of freedom) in tables or parenthetically in the manuscript text. See the example of a peer-reviewed journal article that your instructor has provided for assistance in reporting statistical analysis results. Additionally, narrative summaries of key results in figures and tables must be provided in the text.
The results section should be a straightforward narrative and diagrammatic report of the data. Save narrative comparisons of your results to those of other researchers, speculations of why or why results did not support hypotheses, etc., for the discussion. Only results that are important in supporting or refuting hypotheses, or in meeting objectives should be reported here. However, you should reveal whether or not the hypotheses presented in the introduction are supported.
Discussion
The discussion is where you tell the reader what you think your findings mean, and why they are important. Do the results support the original hypotheses? Why or why not? Compare your results to those of other researchers. Additionally, discuss how your results fit into the bigger picture. In other words, what contributions does your study make to the advancement of science?
In contrast to the introduction section, proceed from the specific to the general level in the discussion. You can begin with a brief summary of your key results, then state why you think these results were found, and compare/contrast your results with those from other studies. Last, how do your results contribute to an improved understanding of the broad problem you studied?
References
In this section, list all references cited in previous sections of the paper. References should be listed in alphabetical order. Use the following examples for proper formats.
Journal articles:
Auerbach, S., F.C. Zhou, and B.L. Jacobs. 1994. Serotonin turnover in raphe neurons transplanted into rat hippocampus. Neuroscience Letters 61:147-152.
Lee, T.D., and F.A. Bazzaz. 1982. Regulation of fruit and seed production in an annual legume, Cassia fasciculate. Ecology 63:1363-1373.
Low, M.G. 1988. Structural and functional roles of various protein anchors. Science 239:269-275.
Books:
McMillan, V.E. 2001. Writing Papers in the Biological Sciences. Bedford Books, Boston, Massachusetts.
Book chapters:
Lowe, R.L. 1996. Periphyton patterns in lakes. Pages 57-76 in R.J. Stevenson, M.L. Bothwell, and R.L. Lowe. eds. Algal Ecology. Academic Press, New York, New York.
Checklist for a Scientific Manuscript
Use the following checklist to assist in constructing your scientific manuscript. When your paper is finished, you should be able to answer “yes” to each question. Note that I will use this checklist as a guide when evaluating your manuscript.
Title
Is the title sufficiently informative?_____
Is the title concise?_____
Abstract
Does the abstract summarize all major sections of the paper, including the introduction, methods, results, and discussion?_____
Does the abstract consist of a single paragraph?_____
Is the abstract sufficiently informative, yet concise?_____
Are citations of references absent, as they should be?_____
Introduction
Does the introduction begin with a review of current knowledge of the general topic to be studied?_____
Are appropriate references cited to support your statements?_____
Are references cited in the proper format?_____
Are your research questions or objectives explicitly stated?_____
Are hypotheses explicitly stated?_____
Does the introduction gradually narrow in focus and conclude with specific questions, objectives, and hypotheses to be addressed in your study?_____
Methods
Are subheadings used to help organize this section?_____
Is the study site sufficiently described? If the study was conducted in the laboratory, has this been made clear?_____
Is the experimental design sufficiently described so that the study can be evaluated and repeated? Are independent and dependent variables identified and described? Has information been provided regarding the number of treatments, the number of replicates per treatment, and statistical analysis techniques used?_____
Is the discussion of procedures restricted to those directly affecting the study results?_____
Are appropriate references cited to support your statements?_____
Are references cited in the proper format?_____
Results
Are tables and/or figures used to summarize the important results?_____
Are tables and figures properly labeled with captions and axes labels?_____
Are tables and figures referenced properly in the manuscript text?_____
Are key results from statistical analyses (e.g., t statistics, critical t values) presented in tables or parenthetically in the manuscript text?_____
Are key results in tables and figures summarized in the manuscript text?_____
Did you indicate if hypotheses were or were not supported by statistical analysis results?_____
Did you correctly refrain from interpreting results, comparing your results of other researchers, and speculating as to why results did or did not support hypotheses, etc.?_____
Discussion
Does the discussion begin with a brief summary of key results?_____
Are all key results interpreted and discussed in light of whether they did or did not support hypotheses?_____
Are key results compared and contrasted with results from other studies?_____
Are appropriate references cited to support your statements?_____
Are references cited in the proper format?_____
Does the discussion gradually broaden in focus and conclude by addressing the broader significance of this research project to advancement of science?_____
Appendix 3. Overview of the paired sample t test
From:
Zar, J.H. 1999. Biostatistical analysis. 4th edition. Prentice-Hall, Upper Saddle River, NJ.
A paired-sample t test is used to determine the significance of the difference between two sets of paired data. In the experimental design described here, initial and final counts of vulnerable snails in each aquarium within one treatment are paired for the analysis. These pairings are based on our expectation that final counts of vulnerable snails in each aquarium should be affected by initial counts of vulnerable snails in addition to whether or not predator cues were introduced.
Two paired-sample t tests are needed to test our experimental hypothesis that snails detect predator cues, then increase use of refuges from these predators. In the first t test we investigate for differences in initial and final numbers of vulnerable snails in the predator-free treatment. This first test is necessary to rule out physical disturbance associated with water transfer procedures as a cause for shifts in snail habitat use, and to separate this disturbance from chemical-cue effects in the predator-cue treatment. We should not find statistically significant changes in numbers of vulnerable snails in the predator-free treatment. However, in the second paired-sample t test (predator-cue treatment), we should find statistically significant declines in numbers of vulnerable snails following addition of water with chemical cues to aquaria.
