Be organized. Work from your outline.

Each paragraph should have one major point. Try to link the theme of each paragraph to the next.

Support all of your statements, preferably with evidence from the scientific literature. If you are guessing, making an arbitrary judgement, or relying on an unsupported assumption, say so. Admit to uncertainty in your or others’ conclusions.

Make sure that your paper accomplishes the goals you set in the introduction.

When finished, make sure to trace the logic of your arguments from introduction to conclusion. Many papers lack logically cohesive arguments or are contradictory. Don’t let this happen to you. It often helps to read work out loud or to have a classmate or friend read it.

Rewriting is the key to good writing. Most writers need to revise their work multiple times. Begin writing your paper well before the deadline so that you have time for rewriting.

Edit carefully. You will likely find yourself having to reorganize, cut unnecessary or redundant sections, and add sections to clarify key points. Do not be discouraged by this?it is part of the normal revision process.

Your writing should be grammatically correct. A good resource for writing is The Elements of Style by W. Strunk Jr. and E. B. White.
 
 

Scientific writing advice

Special formatting rules apply to scientific names.

Scientific binomials and trinomials, and genus names used alone are always italicized (or underlined). The genus should be capitalized; the species and subspecies start in lower case.
    e.g.     Homo sapiens
              Homo sapiens sapiens
               Salamanders of the genus Batrachoseps are the most beautiful of all salamanders.

The first time the scientific name of a species is mentioned, it should be spelled out in full. After that, the genus name is usually abbreviated (e.g. H. sapiens).

Higher taxonomic categories (e.g. families and phyla) are capitalized but not italicized.
    e.g. Chordata, Insecta, Pongidae, Plethodontidae, Scincidae

Many taxonomic category names are also used informally (with different endings), in which case they are not capitalized.
    e.g. Not everyone is as fond of plethodontid salamanders as the author is.

Common names should generally be capitalized (e.g. Turkey Vulture).

Write in a scientific style. In general, discuss ideas, not "papers" or "articles".  Do not talk about the "assignment". Avoid a book report style. Write for a professional audience.

For example, do NOT begin with a long-winded introduction:
Dr. Elizabeth Jockusch and Dr. Ima Nobody of the University of Connecticut published the following paper in the Journal of Evolutionary Biology:  “The role of hybridization in salamander evolution.”

Appropriate would be:  Jockusch and Nobody (2001) investigated how birds use their sense of smell.
 

Avoid excessive quotation:  In general, you should paraphrase what the authors say, not quote it, in scientific writing.  Quoting is appropriate only when the original phrasing is particularly memorable.  Unlike in some fields, where support for a claim comes from citing statements made by authorities, in science, the primary support comes from presentation of the authors' data, not of their words.  Remember that you still must use citations to give credit for the ideas, even when you are explaining them in your own words.

Avoid "touchy-feely" writing that relies on personal experience or feelings.  Your papers should not contain the phrase "I feel that X".  The important question is what you think and what you can support.  (In general, "I feel that X" can be appropriately replaced by "I think that X" in scientific writing).

The word "data" is the plural of "datum". Therefore, it is correct to say that "the data show..." not "the data shows...".