MUW Dept. of Sciences and Mathematics

Biology and Microbiology Writing Style

 

 

1. Style for Essays and Literature Reviews

 

            The style you will use is the style used in the Primers sections of PLoS Biology.  PLoS Biology is an open-acess (that is to say, free) online journal that publishes top tier papers from all areas of biology.  Note that PLoS Biology publishes articles it calls “essays”, but you aren’t using these as your guide.  PLoS essays are more like editorials than literature reviews.  The PLoS primer articles are more similar to what you will be doing in essays and literature reviews.

 

1.  Written instructions from PLoS Biology for the authors of their Primer articles are available here. 

Much of this is directed at the format for research reports, but the information on titles, references, abbreviations, nomenclature, figures, figure legends, and tables all apply to their Primer articles and your essay or literature review.  Scroll down to find the applicable information.

 

 

2.  Here are some recent Primer articles published by PLoS Biology that you can use as guides.  Look at these articles in the pdf format to see the style you should use.  Don’t look at the pages in the web or html format – use the pdf format for viewing the articles to see the proper formatting.

 

The Most Widespread Symbiosis on Earth, by A. Brachmann & M. Parniske.

 

DNA Repair: Dynamic Defenders against Cancer and Aging, by J. O. Fuss & P. K. Cooper.

 

Model Selection and the Molecular Clock, by O. G. Pybus.

 

Chromosomal Organization: Mingling with Neighbors, by J. A. Aten & R. Kanaar.

 

 

PAGE LAYOUT

Just use a single double-spaced column of text.  You should NOT divide your page into two columns of text. 

 

 

QUOTATIONS

Do NOT use direct quotations.  As a general rule, scientific writing paraphrases everything and almost never uses direct quotes.  You must cite what you paraphrase, but you must not plagiarize what you paraphrase. 

 

 

FIGURES

Figures should be incorporated in the middle of the text, not grouped together on separate pages at the end of the essay.  Figures should be incorporated into the text as close as possible to the first reference in the text to that figure.

 

Number your figures sequentially.  Figure 1, Figure 2, etc. 

 

Figures should be boxed with straight lines to make it easier for the reader to know how to distinguish between the text and figures.  (This is not done in PLoS Biology primer essays, but you should do it in your essays.)

 

All figures need a figure legend underneath the figure.  The figure legend should provide enough information to be able to make sense of the figure without having to read the surrounding text.

 

See the sample Primer essays from PLoS Biology for examples on how to incorporate figures and how to write figure legends.   

 

 

CITATIONS

When to use citations

        Every statement that is not common knowledge should be referenced with a citation.  In a densely written essay, sometimes virtually every sentence in the essay ends in citations.  Any piece of material that you didn’t know before hand, that comes from some reference or text, must be referenced with a citation.

 

How to format citations

       Use numbers in square parentheses for your citations.  E.g., “[4].”  Do not put periods inside the parentheses.

 

        Number your citations sequentially in the order they appear in the text.  The first reference you cite is [1], the second reference you cite is [2], etc.  If you cite the same reference more than once, use the same number each time.  That is, once you decide a particular reference is “[7]”, use [7] each time you cite it.

 

        Citations usually go at the end of the sentence.  E.g., “Strigolactones belong to the sesquiterpene lactones, which are believed to have a wide distribution in the plant kingdom [11].”

 

        If, however, you have a sentence that contains information from more than one reference, you can put the citation in the middle of the sentence.  E.g., “The Glomeromycota are considered the fifth fungal phylum [1] and their common ancestor dates back 600 million years [7], yet all of these fungi exist in symbiosis with phototrophic organisms.”  

 

How to refer to authors being cited

        You can occasionally put the name of  the author(s) of a reference, followed by a citation, before summarising the information from that reference, but don’t overdo this sort of thing as it begins to sound affected if used too much.  Only use the authors' surnames, not their first names or even initials.  Do not give them a title or description. 

    The following is an example of how to properly identify authors:

    "Recently, Akiyama et al. [10] provided a major breakthrough in our understanding of the very early recognition events in this process."

   

    The following are examples of how NOT to identify authors:

        "Recently Dr. K. Akiyama and colleagues at Oksaka Prefecture University Akiyama et al. [10] provided..."

        "Recently three scientists in Japan named Akiyama, Matsuzaki, and Hayashi Akiyama et al. [10] provided..."

 

Citations do not replace author names

        If you are going to put citations in the middle of your sentences, the sentence must still be comprehensible when the citation is read out loud without the citation numbers.  Do NOT leave out information that would identify the reference in the absence of the citation number.  So, do NOT write a sentence like, "Recently [10] provided a major breakthrough...".  Instead, write, "“Recently, Akiyama et al. [10] provided a major breakthrough..."

 

More than one citation in a single sentence

        If a sentence contains information that is repeated in more than one reference, you indicate that more than one reference was used in the following manner:

        two references used:  [3,8]

        three or more consecutively numbered references used:  [5-9]

   three or more non-consecutively numbered references used:  [5, 8, 12, 20]

 

Entire paragraphs taken from a single reference

        If you are using a lot of information within a single paragraph from a single reference, you need to cite that reference for each separate piece of information. Note that if you over-rely on a single reference, it becomes immediately apparent because your paragraphs cite the same source over and over again. In general, this is considered poor form and you should make an effort to find other sources of your information if your paragraph looks like this:
        “The heart is located in the thoracic cavity [5]. It consists of four chambers [5]. The upper two chambers are called atria, and the lower two chambers are called ventricles [5]. The left atrium is separated from the left ventricle with a valve called the bicuspidal valve [5]."

 

All quoted examples of proper citation style taken from a PLoS Primer essay by Brachmann and Parniske. 

 

 

REFERENCES

        REFERENCE FORMAT.

        See the sample Primer essays from PLoS Biology for examples on how to lay out and format your references.

 

        References should be listed at the end of your essay.  There should be a left-justified sub-heading of “References” before your reference list begins.

 

        References should be listed in numerical order by the citation number used to identify them in the text. 

 

        All authors should be listed by initials and surname, unless there are more than five authors, in which case only list the first five authors followed by “et al.”  Separate different authors with commas.  Do not separate surnames and initials with commas.  Do not use “and” before the last author.

 

        The full title of the reference should be listed.  Do not put the title in quotes.

 

        For journal articles, accepted abbreviations can be used for journal titles.  Give the volume number of the journal, but do not give the issue number or date.  Give the beginning and end pages of the article, but don’t use “pp” or “pg”.  If the article is available online without charge, include a URL for the article.  Do not include the date you accessed the article; you only do that for web pages that aren't published journal articles.

 

        For web pages that aren’t online journal articles, use the basic format suggested by the Council for Biological Editors (CBE), given here. Scroll down to the section labeled “1.  World Wide Web site” for information on formatting styles for web pages.  Do not use the formatting described in the section "2.  Material from a subscription service."  Modify the CBE format style so that it is consistent with the general features of the PLoS formatting style, such as having the date of publication in parentheses.

 

        For web pages you need to provide the author's name (if known) , date of publication or last revision in parentheses, title of document, title of complete work (if relevant), URL in angle brackets, and very importantly the date when you actually viewed/read the page (“date of access”.)

 

        If the author, document title, and date of last revision are not written on the web page itself (look at the top and at the very bottom of the page; look at the title on the top of your browser window), try right-clicking on the page on choosing "Page Info".  This won't work with all browsers, but is worth trying.  If some of the information (such as author) just is not available, leave it out and go to the next item in the list of information to include in the reference.

 

    For journal articles that are available both online and in print (hard copy), always format your reference as if you had obtained the article from the print version of the journal.  So, even if you go online to read a Nature article, you still format it so the citation includes the journal volume and page numbers, and you do not include the URL or the date accessed.

 

        For information taken from books, give the page number where the information you are citing can be found in the book.  Don’t give the total number of pages for the book.  If the article is from a chapter in a book where every chapter is by different authors, give the chapter title, the book title, the editors of the book, and the page numbers of the chapter (use “pp” to indicate chapter pages.)  Give the city where the book was published (but do not give the state), followed by a colon, followed by the name of the publishing company.

 

        The second and third lines of a reference should be indented to line up with the beginning of the text on the first line.

           

        REFERENCE EXAMPLES

journal articles:

5.  Redecker D, Kodner R, Graham LE (2000) Glomalean fungi from the Ordovician. Science 289: 1920–1921.

 

electronic or online journal articles

6.  Brachmann A, Parniske M (2006) The most widespread symbiosis on earth. PLoS Biol 4(7): 1111-1112. <http://biology.plosjournals.org/archive/1545-7885/4/7/pdf/10.1371_journal.pbio.0040239-L.pdf>.

 

book

7.  Chase JM, Leibold MA (2003) Ecological niches: Linking classical and contemporary approaches. Chicago: University of Chicago Press. p. 212.

 

chapter in book

9.  Simberloff D (1997) Eradication. In: Simberloff D, Schmitz DC, Brown TC, editors. Strangers in paradise: impact and management of nonindigenous species in Florida. Washington (D. C.): Island Press. pp. 221–228.

 

web pages that aren’t online journal articles

10. Daneholt B  (2006)  Advanced Information: The 2006 Nobel Prize in Physiology or Medicine:  RNA Interference.  <http://nobelprize.org/nobel_prizes/medicine/laureates/2006/adv.html>.  Accessed 2007 Jan 4. 

 

11. (2003) CBE home page. <http://www.councilscienceeditors.org>. Accessed 2006 Sept 5.

 

 

        See the sample Primer essays from PLoS Biology for examples of how to structure and format your essays and literature reviews.

 

 

 

 

Return to Writing Style Overview page

 

 

written by:  Ross E Whitwam

last updated:  29 Jan 2008.