Document 198104

How to Write a Lab Report Forest Biology (FRST 200 and 210) Prepared by Ian MacLachlan & Sierra Curtis-­‐McLane 1.
Read this document carefully, it outlines the content and formatting that should be used for lab reports in FRST 200 or 210 and will be the basis for our marking system. You should note that marking for your first lab report will be reasonably relaxed, but in the second and subsequent reports the number of marks deducted for mistakes will increase substantially. We will give you numbers (e.g., 1a, 1b, 2a, 2b, etc.), corresponding to specific feedback comments detailing common mistakes and how to fix them. The numbers and comments will be posted on the course website for your future reference. This system encourages you to rapidly adopt a simple, clear and systematic style of scientific writing. The easier your report is to read the more likely you are to get good marks. Report Purpose: You should aim to produce a clear, concise report that reviews current knowledge on the subject, develops the research objectives, summarizes the methods used, presents the results generated, and then discusses how the results meet the objectives and what they mean relative to the current knowledge or literature that was used to develop your objectives, which may include applications to which this knowledge is relevant. Report Structure & Content: Use the following sections to structure your report. Pay close attention to the section details and suggested content. All sections should be concise and informative. Introduction (1 page max.): The introduction provides readers with the background information required to understand the whole report. Introductions are funnel-­‐like, starting broadly with an introductory sentence that introduces the report’s context (see example 1), and end narrowly with clear definition of specific objectives or questions being investigated in your report (see example 2). Relevant background information fills the funnel and sets up topics that will be covered in your discussion section. Example 1: A good introductory sentence could be, “Germination and early growth differ amongst species, in part as a factor of long-­‐term life history strategies.” Example 2: A good last sentence might be, “In this lab, differences in germination and early primary growth in red alder (Alnus rubra Bong.) and Douglas-­‐fir (Pseudotsuga menziesii Mirb.) seedlings were compared”. You should assume that your reader is educated, but unfamiliar with your subject. Therefore, the introduction should also define and contextualize any terminology that is fundamental to your study. To do this you will need to concisely summarize relevant information from class notes and include background research. Do not include any methods, results or conclusions in your introduction. These are only included in abstracts that summarize scientific research. Materials and Methods (0.75 pages max.): The materials and methods should concisely provide enough information so that your experiment is repeatable. Every critical step of the methods should be explained so that scientific aspects of the experiment can be replicated exactly. Materials and methods must be written in clear sentences, not in point form. Be sure to outline all the different types of data collected, the measurements that were made, and the units of measurement used. Also describe any drawings that were made and their purpose (do not include the actual drawings here). Details of any data manipulation and statistical methods should also be given if used. Do not include unnecessary details about how the lab was performed. For example, another scientist does not need to know that you collected data in groups of three or that the TA dissected a seed for you. Do not copy the lab instruction sheet which describes what you should do during the lab, not what you did during the experiment (see example 3). You should summarise the methods in your own words. 3.
Example 3: “Douglas-­‐fir seeds were cut longitudinally using a razor blade and then examined under dissecting microscopes at 30X magnification” is good, while “Douglas-­‐fir seeds: cut longitudinally and examine under dissecting microscope, 30X magnification” is not. Results (0.75 pages of text max., tables and figures unlimited space): Use the results section to report noteworthy trends in your data. Do not discuss how, why, or what may be the basis for these trends until the discussion section. The results section should include three key elements that are essential to all FRST 200 & 210 lab reports: 1) Tables to display summary values for the data you collected (if you choose to include it, raw data should always be placed in the appendix); 2) Appropriate graphs to show trends in your data; and 3) A paragraph or two summarising the trends observed in the tables and figures. Tables and graphs should be included in the main body of the text, but drawings or photographs can be essential to your results for some reports, and they may be included in the results section or the appendix at your discretion. See the ‘Writing and Formatting Rules’ section below for instructions on how to present and refer to tables, figures and appendix items. Discussion (1.5 pages max.): The discussion section systematically explains possible reasons behind all trends reported in the results section, as well as limitations of the methods used. Writing the discussion always involves using additional sources of information (i.e., references from the scientific literature or from texts, not course notes), statistical interpretation (if any), deductive reasoning and logical inference to explain the results that you reported. Discussion of reported trends should also briefly include suggestions for tests you might perform to validate your explanations. For each trend a simple procedure is to make a statement of what the trend is (see example 4), then follow this statement with explanations of why this trend might have occurred. Example 4: A good discussion sentence stating an observed trend could be, “While the two species displayed similar growth rates over a ten-­‐week period, there was a clear difference in the allocation of resources between root and shoot growth”. After making the statement in example 4, the author could discuss possible explanations for why Douglas-­‐fir seedlings seemed to put more energy into root growth while red alder seedlings prioritized shoot growth. One might also explore other related questions such as, why did the two species have different numbers of cotyledons? Or why does red alder have more lateral roots? In most cases each discussion topic is likely to be a separate paragraph and this should guide the length of your discussion section, but it should be a maximum of about 2 pages. Conclusion (10 lines max.): The conclusion is a concise (usually one paragraph; maximum two short paragraphs) summary of the report’s main findings, why they occurred and what their further implications are. References: List in alphabetical order (according to first author's last name) all the references that you have cited in your report (see the ‘Writing Rules and Formatting’ section for information on using references). Appendix: The appendix contains data and figures that do not belong or fit in the rest of the report. Raw data sheets, sampling maps, or large drawings are common appendix items. They should appear in the appendix in the same order that they are referred to in the text. Only include items in the appendix if they are mentioned in the report and cite them in the same style as tables or figures. To do this, each appendix item needs to be clearly numbered. Not all reports require an appendix. Writing and Formatting Rules: a)
General Writing Etiquette: Proper paragraph formatting, clear sentence structure, good spelling and grammar are basic expectations for all assignments. Reports must be typed, preferably with size 11 font, 1.5 or 2 line spacing, single-­‐ or double-­‐sided printing and no cover page. b) First vs. Third Person: Most scientific journals accept only limited first person language, especially in the introduction and discussion; therefore, it’s a good idea to learn how to write without using the first person. Example 5: Rather than saying, “We measured the seedlings’ total length, root length, shoot length...,” say “Several measurements were taken including total length, root length, shoot length….” Try to use minimal first person references in your write-­‐up. If using first person – stick to using ‘I’ since you performed the experiment and avoid ‘we’ statements unless you have additional authors on your report. c) Using Latin and Common Names: The first time a species name is used, include the whole Latin name and authority (i.e.: Pseudotsuga menziesii (Mirb.) Franco) as well as the common name (i.e.: Douglas-­‐fir). As long as there is no potential for confusion, the genus may be abbreviated following the first use (e.g., P. menziesii) or the common name may be used throughout the write-­‐up. Latin names (in fact all non-­‐English words) must always be italicized or underlined. Common names do not use capitals unless they include proper nouns such as a place or person's name (e.g., black spruce, Sitka spruce and Douglas-­‐fir are all correct, whereas Black Spruce, sitka spruce and douglas-­‐fir are all incorrect). d) Citations and References: Citing and referencing appropriate literature is an essential component of all scientific reports. We expect you to use up to 5 or 6 additional peer-­‐reviewed scientific papers in journals for your reports. You can find these by using search engines such as Web of Science (available through the UBC Library) or Google Scholar, and access them through the UBC Library. A citation is required whenever you use information from somebody else’s text or their ideas. ‘Citation’ is the mention of literature in the main body of your text, whereas a ‘reference’ is the full bibliographic information for a given citation that is listed in the reference section. You should use the ‘author – date’ citation style given in the reference writing instructions document provided on the FRST210 course website. e) Measurement Units: Report your data using appropriate SI (i.e., metric) units and always give the units of measurement for any data when it is first mentioned in your report as well as in every table or figure. Think carefully about what your measurements mean in reality to determine the appropriate number of decimal places or significant figures that should be used. f) Figures and Tables: What They’re Good For: Figures such as graphs, drawings and photographs are tools for illustrating written content that is not otherwise easy to visualize. Tables present values that summarise raw data across several categories or variables. In your FRST 200 & 210 reports, tables and figures are essential requirements because formal statistical analysis is optional, but we still expect you to identify and discuss trends. Formatting Rules: When creating a figure or table ask yourself what you’re trying to demonstrate to the reader and stick to the following rules: • Do not use snazzy graphics – we will not be impressed. We are looking for figures that are simple, clear and informative. • All graphs and tables except the first graph of the stem analysis lab (FRST 210) should be word processed. • Size matters – don’t use small figures. As a guideline, graphs should be full-­‐page-­‐width. Table size depends on the amount of data, if the table doesn’t fit on a single page it belongs in the appendix. • Figures and tables are separate entities – do not label tables as figures. • Don’t give graphs a title, even though the Excel default does. This information is provided by the caption. • Label each axis of a graph with the variable it represents and the units of measurement. • Consolidate two or more trends (i.e., data sets) in the same graph if they have identical units of measurement and values in the same order or magnitude. •
Include a legend if you have more than one trend per graph and make sure that the colours or symbols are organized such that the reader can draw fast visual conclusions about each trend. Drawings include a scale bar and must be clearly labelled with any parts described in your report. •
Citing Figures and Tables: Figures and tables can never stand alone; they must be cited and explained in the results section. It is best to cite a figure or table in parentheses at the end of the respective sentence (see example 6). It is never acceptable to simply list attached figures or to say “see attached figures”. All figures and tables should be positioned in the report close to the relevant paragraph and in the same order that they are mentioned in the text, so the reader is not confused trying to find the correct figure. Example 6: “The average total length of P. menziesii and A. rubra increased at approximately the same rate over the ten week growing period (Figure 1).” Figure and Table Captions: Every figure and table must have a caption that includes a number and a brief written description (in complete sentences) of what the figure contains, but doesn’t describe any trends (see example 7). Captions for figures (graphs and drawings) are placed below the figure, but captions for tables are placed above the table. Example 7: A good example of a figure caption might be “Figure 1: Root, shoot and total growth in A. rubra vs. P. menziesii over a ten-­‐week period.” Bar Graphs, Line Graphs and Scatterplots: Your chosen graph should be determined by the type of data on your x-­‐
axis. Bar graphs are only used when the x-­‐axis is categorical (e.g., “pines”, “spruces”, “firs”), but line graphs are required whenever the data is continuous and shows change from one measurement point to the next (e.g., latitude, longitude or a time series such as day of year). Scatterplots are used to display numerous data points for continuous x-­‐ and y-­‐axes. Data points on line graphs can be connected, but never use a smoothing function in your FRST 200 & 210 lab reports. Points in scatterplots should never be connected with lines, but if you want to show a general trend in your data in a scatterplot, you can insert a line of best fit through the data points (called a trend line in Excel). Useful Hints and Tips: a) The secret to writing great lab reports: Your first lab reports can be daunting and challenging to write, but once you’re familiar with the format they will become much easier and obtain higher marks. We recommend writing the materials and methods section first because it’s simple, straightforward and familiar to you. Next, analyse your data, create your graphs and write the results section. Then write the discussion. Finally, although it’s counterintuitive, finish by writing the introduction. This should make the content of the introduction easier to judge and prevent it from being too short or long. b) Include only meaningful information: A good scientific writer will use the minimum number of words possible to clearly state their point, so don’t use sentences that don’t tell the reader anything meaningful. For example, “This lab was interesting and helpful for understanding germination better” tells the reader nothing what you learned, so leave it out. c) The Meaning of ‘Significant’: In science, ‘significant’ refers to the outcome of a statistical test. We’re not doing statistical tests in most of these labs, and don’t mind if you use the word significant to mean “highly notable”, but do not try calling a trend notable when it isn’t. d) Avoid Making Overly Large Scientific Inferences: Extrapolation of your data trends to larger scientific concepts will be required; however, it is not acceptable to do so without adequate supporting information. For example, applying the concepts learned from observing physiological differences between red alder and Douglas-­‐fir to all angiosperms and gymnosperms would be inappropriate. Unfortunately, a small amount of research will show you that red alder and Douglas-­‐fir do not show germination or primary growth trends that are necessarily representative of their respective phyla. You need to use valid scientific references to support any conclusions you draw or speculations you make based on your results. When you are suggesting possible explanations for results, if those are speculative, write it in a way that reflects the uncertainty, e.g., using words such as “may result from”, or “could be explained by”. If you want to know more about how to write good scientific papers, there is lots of information available online. One particularly user-­‐friendly resources is: