Guide: Biology Research Papers

Biological Research Papers Style Guide

These are instructions for writing a research paper that is the result of an original laboratory or field investigation. These guidelines would be modified for library research papers since they have a slightly different format; specifically, they may lack methods and results sections, and may have ad hoc names for major headings (TYPES OF SECONDARY SUCCESSION, PERCEPTIONS OF GEOLOGIC TIME BEFORE 1990, etc.).

1. Title

The title should be centered, about 2" down on the first page, and typed in all capital letters. It does not need to be in italics or quotation marks, and it is obvious that it is a title, so it does not need to be labeled as such. A good title is short and accurately describes the content of the paper. A title would be long and involved only when there is no other way of conveying the content of the paper to the prospective reader. There is often an inverse relationship between the scope of a paper and the lengths of its title.

There are three styles:

Indicative Titles Indicative titles simply indicate the content of the article (e.g., “Post-fire succession in a lodgepole pine forest”). Descriptive Titles Titles may be descriptive (“Post-fire succession in lodgepole pine forest is faster on granite than basalt soils”), giving the reader a one-sentence summary of the most striking result. Interrogatory Titles Titles may also be interrogatory (“Is succession in lodgepole pine forest faster on granite or basalt soils?”), trying to “hook” the reader with a catchy but appropriate title (the marketing approach).

2. Authors

The author or authors name(s) go under the title in mixed upper and lower case letters. Order of authors is usually in order of their respective contributions. If the authors all contributed equally, the order of authors can be determined by any mutually agreeable manner. Alphabetical order and coin tosses are popular methods. The preposition “by” is typically omitted (e.g., “by George Jones”). The author’s address can be included (e.g., “Department of Biology, The College of Idaho, Caldwell, Idaho 83605”) as is seen in professional papers in journals.

3. Abstract

The abstract is a short statement of the essence of the paper. It clearly states 1) the problem, 2) the methods of investigation, 3) the results, and 4) the conclusions and implications in one succinct paragraph. An abstract should not exceed 5-10 percent of the length of the paper.

You must select only the most essential details to include in the abstract. Keep it short. Make every word count. For many people, it is easier to write the abstract after writing the rest of the paper. Writing a good abstract forces one to think clearly about what was really accomplished.

An abstract should be specific rather than vague and general. When the results are quantitative and significant, the abstract should include numerical results. For example, compare the following two statements: “Oxygen levels in Indian Creek were significantly lower (3.2 ppt) downsteam of Nampa than above (5.4 ppt; t = 5.6, P< 0.001) …” with “We include data on oxygen levels above and below Nampa.”

It should be double-spaced, like the rest of the manuscript. An abstract is never written in the future tense (eg. "We will investigate the effects of caffeine on laboratory rats.") because it is a summary of work that has already been completed. It (and most of the rest of the paper) should be written in the past tense ("We investigated the effects of caffeine on rats.")

The abstract has to stand alone and independent. Therefore, don’t cite literature (or if you must, use an abbreviated format. As an example using one of the references above, Hershkovitz (1949) would be cited as (Hershovitz, 1949, J. Mammal. 30:289-301).

4. Introduction

All papers must have an introduction. It should be labeled as such, although some journals leave this section of the paper unlabeled. The introduction "sets the stage" for the rest of the paper by orienting the reader. It tells briefly what you set out to do, what has been done before by others, why you did the research, and why the work was important. The introduction is the place to "paint the big picture" so that the reader will realize what is original and significant about your work.

Never say "I did it to get a grade," or "I did it because it was assigned." The professional researcher, after all, does not say, "I did it to get a pay raise," or "I did it to fulfill the terms of my grant."

Generally, the opening sentences should be a clear statement of the problem or hypothesis. This is followed by a concise review of the literature relevant to the problem. Be as thorough as possible with the literature review. One reason for doing a literature review is to be certain what you plan to do has not already been done by someone else. Do the literature review BEFORE starting the investigations. Otherwise, you may expend much energy "reinventing the wheel." Begin with the earliest known observations on the subject (Aristotle and Darwin seem to have many first observations!). Scrupulously avoid plagiarizing by giving credit for every fact and idea that is not your own original contribution.

5. Methods

Science is the business of producing reproducible results. An investigation is scientific only if it has the potential of being repeated by another investigator following the procedures given in your methods section. The methods section also allows others to evaluate your results, even if they have no intention of repeating them. It is labeled METHODS or sometimes METHODS AND MATERIALS if many supplies were used.

The methods section records the procedures you used in enough detail to allow another investigator to repeat the work. Omit trivia, such as how you label the test tubes or where you placed them on the shelves, but do include any details which could have influenced your results. If a power surge raised the temperature of your cultures, or you didn't set your traps at one location until after midnight, or it snowed the night before your behavioral observations, record these events in the methods section so that others can evaluate your results. Include such types of information as the variety of seeds used, the exact location of your study area, the dimension of your trapping grid, the strain of fruit flies, the concentration of reagents, the wave lengths of radiation, and (where pertinent) the brand names and model numbers of equipment used. How did you choose your samples? Are your water temperature readings from random depths or fixed intervals? Were they all taken at the same hour every day?

Avoid the type of running explanation which goes, "First I did this, and then I did that." This mindless "cookbook" narrative is boring and also leaves out the reasons for using each of the procedures you catalogue. Tell why you used the procedures you did. Be concise and to the point. Remember to use the past tense.

If you used a method developed by someone else (which happens quite often in science), you must cite the reference for that method (e.g., "I estimated differences between samples using the Student-Newman-Keuls procedure [Sokal and Rohlf 1981]”). If part of your procedure involved using a specific method, by citing the original source of the procedure you free yourself to the necessity of having to explain the method in your paper. A few methods are so well-known (chi-square test, for example), that is no longer necessary to cite an authority. But until you get a "feel" for these, it is safer to cite the source.

Avoid the passive voice; it can be ambiguous and boring. If you say, "It was discovered," the reader will wonder if you discovered it, or if someone else had discovered it earlier. Use the active voice: "I found --" or in a co-authored paper "We found ---."

All measurements should be taken and reported in metric units. Time should be referred to using the 24-hour clock (1700 hours, not 5:00 p.m.), and dates should follow the continental system (17 January 1985 rather than January 17, 1985). If you take measurements in the English system, provide metric equivalents.

6. Results

This section reports your data. It is labeled RESULTS and includes:

  1. a verbal account/written summary of your findings,
  2. tables and/or figures to display numerical data in greater detail
  3. any statistical analyses of the data.

Data which consists of numbers is best displayed in tables and/or figures. The text summarizes data found in the tables and figures but never restates it, number by number. Tables and figures must be mentioned or referred to in the written text, to direct the reader's attention to the appropriate figure at the appropriate time.

The results section does not include interpretation or discussion, although you may use the results section to report that your findings are new and/or unique.

  • Tables and Figures

Tables and figures should have captions which explain the contents in enough detail that the figures or tables are understandable without reading the paper (for example: "Fig. 1. Percent chromosome breakage in 60 white rats after injection of caffeine at daily intervals").

What is the difference between tables and figures? Tables consist of columns and rows of numbers. The caption appears at the top of the table. Each column is clearly labeled. Please give careful attention to the logical arrangement of each table so that it can be interpreted easily! Tables should be numbered consecutively with Arabic numerals (Table 1, Table 2, etc.) in the order in which they are mentioned in the text.

Figures are maps, graphs, charts, histograms, drawings, photographs, or other visual presentations of data. Figures are captioned at the bottom and should also be numbered sequentially with Arabic numerals in the order mentioned in the text (Fig. 1, Fig. 2, etc.). The same data should not be presented both in a table and in a figure. The independent variable is plotted on the x axis of a graph and the dependent variable on the y axis. Tables and figures can be placed in order at the end of the paper after the literature cited.

7. Discussion

You discuss your results in this section; it is labeled DISCUSSION. Here you tell the reader what you have found that is new, what your results mean, and why the results are important. It is also the place in which to discuss any anomalies in the data, compare your results with your expected results, compare your results with the results of others in the literature, and perhaps suggest possibilities for further study.

The discussion is an interpretive section, but your interpretations must be supported by the data. Don't make statements you cannot support. Be careful with speculation. Do not "stack you cards" by citing only data and authors that support your point of view. You must deal openly with opposing views: "Smith (1972) found fewer species in his study, but his study was not done during the breeding season..." Do not fail to mention problems or ambiguities which are difficult to explain. Discuss any disagreement between expected and actual results.

Finally, return to your initial statement of your problem and draw a conclusion that is supported by your data. Sometimes you will conclude that no conclusion can be drawn. While this isn't very satisfying, it is a legitimate conclusion.

8. Acknowledgements

It is customary to have a section between the discussion and the literature cited sections in which you thank all the people and institutions that have aided you in your study, record the use of grant or institutional funds, and give credit for ideas which are not directly credited in the body of your text.

9. Literature Cited

The final section is usually a "literature cited" rather than a "references" or "bibliography" section. A literature cited section includes just those references you actually cite in the text. (A "references" section includes all the works that you cite, plus some that you do not cite but which are relevant to the subject. A "bibliography" is a exhaustive list of all that has been written on a subject.).

The entries in the literature cited section are placed in alphabetical order, and then arranged chronologically (Jones 1982, Smith 1995a, Smith 1995b, Smith 1996, Smith and Jones 1994, Smith and Wesson 1992, Smith and Wesson 2003). Entries are usually not numbered, and all of the references should be included in a single list rather than in sublists of books, periodical articles, theses, etc. Note that book and journal titles are not italicized or underlined in this section because their position in the entry makes it obvious what they are. Here are several examples of correct form:

  • Journal Format

Conover, D. O., and S. B. Munch. 2002. Sustaining fisheries yields over evolutionary time scales. Science, 297:94-96.

Dyer, N. W., and L. E. Huffman. 1999. Plague in free-ranging mammals in western North Dakota. Journal of Wildlife Diseases, 35:600-602.

Ebensberger, L. A. 1998. Strategies and counterstrategies to infanticide in mammals. Biological Reviews 73:321-346.

French, A. R. 1988. The patterns of mammalian hibernation. American Scientist 76: 568-575.

Griffith, B., J. M. Scott, J. W. Carpenter, and C. Reed. 1989. Translocation as a species conservation tool: status and strategy. Science 245:477-480.

  • Book Format

Verts, B. J., and L. N. Carraway. 1998. Land mammals of Oregon. University of California Press, Berkeley, California.

  • Thesis Format

Harmin, S. A. 1979. The influence of selected water quality parameters on the growth of fish in Tobacco Juice Creek. M. S. thesis, Mississippi State Univ. 375 pp.

Holekamp. K. E. 1983. Proximal mechanisms of natal dispersal in Belding's ground squirrels (Spermophilus beldingi beldingi). PhD Dissertation, University of California, Berkeley, California.

  • Edited Volume Format

Holekamp, K. E. 1984. Dispersal in ground-dwelling sciurids. Pages 297- 320 in J. O. Murie and G. R. Michener (editors). The biology of ground- dwelling squirrels. University of Nebraska Press, Lincoln, Nebraska.

  • Multiple citations in same year by an author

Michener, G. R. 1993a. Lethal myiasis of Richardson’s ground squirrels by the sarcophagid fly Neobellieria citellivora. Journal of Mammalogy 74:148-155.

Michener, G. R. 1993b. Sexual differences in hibernaculum contents of Richardson’s ground squirrels: males store food. Pages 109-118 in C. Carey, G. L. Florant, B. A. Wunder, and B. Horowitz (editors). Life in the cold: ecological, physiological, and molecular mechanisms. Westview Press, Boulder, Colorado.

Sherman, P. W. 1981a. Kinship, demography, and Belding's ground squirrel nepotism. Behavioral Ecology and Sociobiology 8:251-259.

Sherman, P. W. 1981b. Reproductive competition and infanticide in Belding's ground squirrels and other organisms. Pages 311-331 in R. D. Alexander and D. W. Tinkle (editors). Natural selection and social behavior. Chiron Press, New York, New York.

All lines after the first line on which a reference is written are normally indented. No quotation marks are used. In the literature cited, an entry such as "Scientific American, 222: 13-21" means that the article is found in volume 222 of Scientific American on pages 13 to 21. The name of the first author is inverted; the others are not. Only proper names and the names of taxonomic groups are capitalized in titles. Only the names of genera and species appear in italics (underlined). (Note that the journal name, above, is underlined or italicized when used outside the Literature Cited section, as it is here.).

Some of your sources may abbreviate the names of journals, e.g., “Sci. Am.” for Scientific American, “J. Wildl. Dis.” for Journal of Wildlife Diseases, etc.

Journal titles are abbreviated according to standard lists such as the BIOSIS List of Serials. (If you do not have access to such a list, a safe procedure is to consult the journal you are using as a style guide and abbreviate journal titles the same way or write out the entire name of the journal, as is more common in recent years.)

10. Citing Sources in the Body of the Text

Any information (data, figures, ideas, etc.) that is not original with you in this paper must be cited. Failure to cite the sources of your information is plagiarism. Plagiarism is one of the worst academic crimes, and is in the same category as cheating on exams. AVOID IT BY SCRUPULOUS USE OF LITERATURE CITATIONS!

There are several systems for citing literature in scientific papers. The author-date system is the most widely-used system in science, and is also the simplest to use. It is explained below. (Please note that footnotes, ibid., op. cit., etc. are not used in scientific papers.)

Rather than using a footnote to point out the source of your information, simply incorporate the last name of the author(s) and the year of the publication into the sentence in which the borrowed information is included: (Smith 1985). Two authors are both listed (Smith and Jones 1985); but for three or more authors (of the same paper), use et al. (Smith et al. 1985).

If several sentences take their information content from one source and this is obvious from the way your paragraph is written, you do not have to repeat the citation in every sentence as long as it is apparent to the reader that all of the material is coming from the same source, but at least there must be a citation at the end of the paragraph.

The sources you cite are listed, of course, at the end of the paper in the literature cited section. For direct quotations, the page number on which the quoted passage is found must be given (Jones 1976:111); do not give the page number in a citation unless it is a direct quotation. If you wish to quote part of the sentence but not all, use ellipsis periods to indicate omitted material (see examples 4 and 5 below).

Here are six examples of the use of the author-date system. Notice the use of parentheses, periods, and commas in these examples.

  • According to Honacki et al. (1982), there are two species of Dolichotis in South America.
  • There are two species of Dolichotis in South America (Honacki et al. 1982).
  • The Patagonian "hare" (Dolichotis) is convergent with North American jackrabbits (Vaughn 1978). There are two species of Dolichotis (Honacki et al. 1982) which differ from other members of the rodent family Caviidae by having elongate legs, long ears, and a general resemblance to rabbits (Paradiso and Nowak 1983).
  • This thought was clearly expressed by Darwin (1871:436), ". . . we must acknowledge . . . that man with all his noble qualities, with his god-like intellect which has penetrated into the movements and constitution of the solar system . . . still bears in his bodily frame the indelible stamp of his lowly origin."
  • "Doing science is not such a barrier to feeling or such a dehumanizing influence as is often made out. It does not take beauty from nature. The only rules of scientific method are honest observations and accurate logic . . .no one should feel that honesty and accuracy guided by imagination have any power to take away from nature's beauty" (MacArthur 1972:1).
  • Goodenough and Levine (1970) believed that the photosynthetic and structural lesions of mutant ac-20 Chlamydomonas reinhardtii were quite similar to cells in which protein synthesis was blocked by chloramphenicol. However, other investigators (eg. Smith 1971, Jones 1973, Smith and Jones 1974, Smith et al. 1975) did not agree.

What if you cite two papers written in the same year by the same author? The first article to be published (if you can determine that) becomes Smith 1975a, the second becomes Smith 1975b, and so on. In the literature cited section, be sure to include the a and b after the year for each article, and list them in this order.

Suppose that you find a passage written by Charles Darwin in a paper by Smith (1979), and you wish to quote Darwin's words but you haven't actually seen Darwin's the original source; therefore, you cannot know if Smith quoted him accurately. What you do in this case and in all others in which you haven't seen the original source is to cite it as follows: (Darwin 1859, in Smith 1979). Cite both Darwin (1859) and Smith (1979) in the literature cited section.

Direct quotations are used infrequently in scientific writing. It is often better to put the material of others into your own words; your paper will read more smoothly and will contain only the most relevant material. But make them your own words, and make the sentence structure your own. Do not change a few words and call the material your own; this is still plagiarism. Direct quotations must be word for word, comma for comma, absolutely the same.