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Page 1: Writing a Scientific Paper - Biology1experience's Blog · Writing a Scientific Paper Department of Biology, George Mason University ... o Incomplete sentences, mismatched nouns and

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Writing a Scientific Paper Department of Biology, George Mason University http://classweb.gmu.edu/biologyresources/writingguide/ScientificPaper.htm

A well-written scientific paper o explains the scientist’s motivation for doing an experiment, the experimental design and

execution, and the meaning of the results o is written in a style that is exceedingly clear and concise o informs an audience of other scientists about an important issue and documents the

particular approach used to investigate that issue.

Tips for Good Scientific Writing University of Wisconsin – La Crosse http://www.uwlax.edu/biology/communication/Recipe.html

Have knowledge and mastery of the subject area o Carefully read relevant reference materials

Use a working outline o Write and rewrite your hypotheses/objectives until they are simply and clearly stated

Consistently focus on your hypotheses and objectives o As you write, always think, “Does this directly pertain to my hypotheses or objectives?”

Create well-written paragraphs o Clear topic sentence: introduces the general topic covered in the paragraph o Other sentences

Logically connected to topic sentence Maintain a logical flow of ideas

Have an understanding and mastery of key technical words and phrases o Improper use of technical terms (or not using them at all!) is a clear indication that your

understanding of the subject matter is incomplete. o Proper use of such terms results in writing that is clearer and more concise.

Avoid glib superlatives, colloquial expressions, and awkward phrases o Maintain an objective, unemotional, and professional writing style o Examples to avoid: “Fantastic”, “Very”, “Terrific”, “Since the dawn of history…”

Avoid common writing errors o Incomplete sentences, mismatched nouns and verbs, misspelled words, use of quotes,

use of contractions, improper use of common words (e.g., affect vs. effect, data vs. datum, since vs. because), writing numbers less than 1.0, writing numbers (e.g., 5 vs. five, fifteen grams vs. 15 grams), writing species names, using “et al.”

o For more errors to avoid: http://www.uwlax.edu/biology/communication/DirtyDozen.html

Page 2: Writing a Scientific Paper - Biology1experience's Blog · Writing a Scientific Paper Department of Biology, George Mason University ... o Incomplete sentences, mismatched nouns and

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Writing an Introduction University of Wisconsin – La Crosse http://www.uwlax.edu/biology/communication/ResearchManuscripts.html

The introduction should o establish the existing state of knowledge of your research topic o identify the specific focus of your work

Information typically flows in the following manner: o Start with a broad background

Start with a relatively broad background of the topic you are investigating. Include relevant citations from primary literature and other appropriate technical references.

o Progressively narrow the scope Progressively narrow the scope of the ideas considered so that the reader is led to

the specific topic that you are studying. Using primary literature, justify how this topic requires additional study.

o State 1-3 specific objectives or hypotheses In the last sentences of the final paragraph, succinctly state 1-3 specific objectives or

hypotheses that your study addresses. A crystal-clear statement of objectives/hypotheses is critical. Virtually all material in your manuscript should directly pertain to these objectives and hypotheses.

Example of an Introduction

Although the water economies of a number of species of amphibians have been studied, the majority of these investigations have been interspecific in nature (Smith et al., 1998). Such studies have often sought to elucidate adaptive differences among species inhabiting different habitats (Thorson and Svihla 1943, Littleford et al. 1947, Thorson 1955, Schmid 1965, Farrell and MacMahon 1969, Ralin and Rogers 1972, Gillis 1979). Comparable adaptive differences may also occur between developmental stages of a single species, especially when these stages occur in different environments. However, correlations between developmental stage and ecophysiological parameters have been relatively unstudied.

The red-spotted newt (Notophthalmus viridescens) has a more complex life cycle than many amphibians. In most amphibians, an aquatic larval stage is followed by the adult stage that occurs in either aquatic or terrestrial habitats. In this species, however, larvae develop rapidly and metamorphose into terrestrial salamanders, the red-efts. After spending up to seven years in terrestrial habitats, these subadults go through a second metamorphosis to become aquatic adults (newts) that spend the remainder of their lives in water (Conant 1975).

In view of the difference in habitats occupied by these two stages it was hypothesized that newts and salamanders should differ in terms of their water economy. Specifically, terrestrial efts should have lower rates of evaporative water loss and be more tolerant to dehydration than aquatic newts.

Page 3: Writing a Scientific Paper - Biology1experience's Blog · Writing a Scientific Paper Department of Biology, George Mason University ... o Incomplete sentences, mismatched nouns and

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o Note how the introduction started with a relatively broad idea (water economies in amphibians) and that it identified a general “hole” in the literature (that most studies have studied interspecific patterns – that is, “among-species” patterns rather than “within-species” patterns).

o In paragraph 2, note that the topic is narrowed to introduce the species studied in this investigation.

o The final sentences of the Introduction state the hypotheses considered in this study. o Thus, the Introduction looks like an upside-down triangle -- broadest topic at the top

and progressively narrows to a "point" which is the statement of specific hypotheses or objectives.

o Also note that the Introduction includes a number of citations to primary literature.

Criteria for Grading the Introduction

Criteria Points

1. Demonstrates good biological insight, understanding, and accuracy 3

2. Reviews and interrelates relevant scientific literature 2

3. Cites literature correctly; used name-year convention 1

4. Logical flow of ideas – starts broadly, then leads to specific topic, then ends with clearly and concisely stated 1-3 hypotheses/objectives

3

5. Well-constructed paragraphs, no writing errors, etc 1

TOTAL 10

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Writing the Materials and Methods University of Wisconsin – La Crosse http://www.uwlax.edu/biology/communication/ResearchManuscripts.html

In writing the Materials and Methods section, you need to o describe what you did in such a way that other scientists can follow and duplicate your

experiment o decide how much detail to give the reader

too much detail can make this section excessively long be concise, but complete

Other pointers o Write in third person and past tense. o Describe what you did. o Do not tell the reader how to do the experiment as if you were writing a cookbook or

lab manual. o For field studies, include the locations and times that data were collected. o Avoid the use of slang or jargon.

Good Examples of Materials and Methods

"Twenty-five µl of each sample were loaded onto a 10% polyacrylamide gel and subjected to electrophoresis for one hour at 120V."

o Comment: The number 25 is spelled out . Although this number is greater than nine, and hence would normally be expressed as "25," numbers at the beginning of sentences are always spelled out. In addition, the abbreviation for microliters is used, and the sentence is written in third person and past tense. This is a good sentence!

"Newts and efts of N. viridescens were collected in Cattaragus County, New York in September 1982.

Animals were dehydrated in an apparatus similar to that used by Ray (1958). Compressed air from a SCUBA tank was adjusted to enter a 6 x 6 x 32 cm chamber at a flow rate of 2 l/min. Prior to entering this chamber, the air passed through a column of CaCl2. The entire apparatus was maintained at a temperature of 20-22°C. Food was withheld from all specimens for 3-5 days prior to testing to ensure their being in a postabsorptive state. Before being placed in the chamber, each animal was dried with absorbent paper, its bladder was emptied by applying gentle pressure to the abdomen and total length (cm) and mass (g) were recorded.

Dehydration was continued to the critical activity point (CAP), the point at which animals lost their righting response (Ray 1958). At this time, each specimen was removed from the chamber, weighed and placed in a dish containing water-soaked cotton. Only individuals that survived 24 h after testing were used in the statistical analysis of these data. All means were compared with the t-test while analysis of covariance (ANCOVA) was used to compare the regressions of rate of water loss on body mass (Sokal and Rohlf 1973)."

o Comment: Note how clearly and concisely these paragraphs were written. They were not overly detailed, although all needed information was presented.

Page 5: Writing a Scientific Paper - Biology1experience's Blog · Writing a Scientific Paper Department of Biology, George Mason University ... o Incomplete sentences, mismatched nouns and

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Poor Examples of Materials and Methods

"Take 25 µl of each sample and load them on a 10% polyacrylamide gel."

o Comment: Avoid telling the reader what to do; tell them what you did. "Next I would take 25 µl of each sample and load them on a 10% gel."

o Comment: Avoid the first person. Write in third person and past tense. "1. Load 25 µl of each sample on a 10% polyacrylamide gel. 2. Run the gel at 100 V for 30 minutes. 3. Transfer the gel to nitrocellulose for one hour at 70V."

o Comment: Avoid lists. Describe what you did in sentences. "25 µl of each of the 3 samples were then loaded on a 10% polyacrylamide gel."

o Comment: Avoid starting sentences with numbers or abbreviations. In addition, spell out numbers less than 10.

"Then we ran the proteins on a gel."

o Comment: Avoid slang ("ran the proteins") and first person. "Twenty five µl of each sample were drawn up and loaded onto the top of a 10% polyacrylamide gel. Buffer was then added to the upper and lower chambers and the electrodes were connected. The samples were then subjected to electrophoresis for one hour at 120V."

o Comment: Factually correct, but three times longer than necessary. "Samples were subjected to electrophoresis on a gel."

o Comment: Too little detail.

Criteria for Grading the Materials and Methods Section

Criteria Points

1. Accurately described what was done, w/o giving instructions 2

2. (Statistical and) Quantitative methods were explained 2

3. Concise and complete 2

4. Cited literature correctly; used name-year convention 1

5. Written in the 3rd person, past tense 2

6. Well-constructed paragraphs, no writing errors, etc. 1

TOTAL 10