What a critique is: Your goal in writing a scientific critique is to evaluate the scientific merit of a paper.  You will consider strong and weak aspects of the scientific content of a paper and determine what can really be concluded from the research reported in the paper.  Note that in a critique you can conclude that all the paper's conclusions are very strong, that they are all very weak, or, most commonly, that some are strong and others weak.  The important point to a critique is that you evaluate and explain why you reach the conclusions you do.

For this class, you will write a critique of a paper in which a phylogeny of some group of organisms is developed, and used to draw conclusions about some aspect of the evolution of those organisms.  You will focus on evaluation of methods used to construct the phylogeny, methods for using the phylogeny to reach conclusions about evolution, and how strongly the resulting phylogeny supports the conclusions that are given in the paper about the evolution of the group.  You will use your knowledge of these areas from lecture and from the textbook to help you critique this paper.
 

• For Spring, 2003, the required paper is: Parker, J.D. and S.M. Rissing.  2002.  Molecular evidence for the evolution of workerless social parasites in the ant genus Pogonomyrmex.  Evolution 56: 2017-2028.

There are some terms used in this paper that may not be familiar to you and that we haven't learned in class.  Click here for some comments on the assignment with regard to this particular paper, and definitions of some terms.

Instructions for writing your critique: You will write your critique in standard essay format with an introductory paragraph or two in which you present background and a thesis which you will support through the rest of the paper, a body of the paper in which you develop points relevant to your thesis, and a concluding paragraph in which you tie the points you made in the body together and reach your final conclusions about the paper.  Specifically, the sections of your critique should have the following information:

Introduction: give brief background on why the questions being studied in the research paper are of interest in evolutionary biology.  Explicitly state the hypotheses being tested in the research paper, and the predictions of the hypotheses that are tested.  Give a one to two sentence summary of the methods -- no detail, just the basics of what was done, and then state the main conclusions about the hypotheses by describing how the phylogenetic pattern discovered does or does not meet the predictions of the hypotheses.  Finally, give a thesis statement which includes YOUR conclusions about what can REALLY be concluded about the paper, based on evaluation of the methods and results.  Be specific: briefly state what weak or strong aspects of methods or results make some specific conclusions well or poorly supported.

Body: to evaluate the methods and results of the paper, address the following three questions (don't number them as questions, but do address the material in the questions.)

1.  How well did the researcher(s) select study organisms, populations, and characters to test their hypothesis?  Consider whether there are enough populations, species, and/or species groups to test the hypothesis well, whether adequate outgroups were used for phylogenetic analyses, whether appropriate characters were selected for phylogenetic analysis, and whether appropriate ecological, structural, and/ or geographical factors (choose those that are relevant to the paper) were studied to address the hypothesis being tested.

2.  How well did the researchers conduct their phylogenetic analyses?  Evaluate the methods of character and phylogenetic analysis used by the researchers, and the methods they used to check the validity of the hypotheses of phylogeny they obtained.

3. How well do the phylogenies presented by the researchers support the conclusions about evolution reached by the researchers?  Here, you should consider the pattern observed in the phylogeny really supports the conclusions stated, and whether any parts of the phylogeny that may not be well supported are crucial to the some or all of conclusions about evolution drawn by the researchers.

Conclusion: In your final 1-2 paragraphs, give a justified explanation of what can really be concluded about the hypotheses being tested by the results obtained in the paper.  Your conclusion must be based on the points you have evaluated in the body of the paper.  You should not add any new points of evaluation here; rather, you should consider whether any problems you have identified are likely to be so serious as to invalidate some or all of the conclusions, and whether any strong points you have identified make some or all of the conclusions very well supported.

Literature Cited: At the end of the paper, present a literature cited section in which you give the citation for the research paper (this should be copied EXACTLY from the way it is presented above, where the research paper is assigned!)  If you used information from the textbook, you should also cite it.

Grammar and Style: Be sure to use appropriate grammar, style, and format for citing papers both in the body of the paper and in the literature cited section at the end.  Information on all of these aspects of grammar and style is given on Rebecca Irwin's web pages on scientific writing; click here to see them and READ THEM CAREFULLY!!!

Some Important Final Notes:

• the author(s) of a paper may or may not explicitly state these hypotheses; if they do not, then it is up to you to figure out what the hypotheses, which should be presented as explanations of some aspect of evolution or pattern of character distribution amon species, really are!  Since points in the introduction, body, and conclusions of the paper are based on the hypotheses, it is VERY IMPORTANT that you determine what they are; feel free to ask me for help.
• when considering aspects of the methods, focus on the methods of phylogenetic analysis; do NOT spend much (or any) time evaluating methods such as molecular methods used to come up with DNA sequences -- if you were evaluating this paper for a class in molecular biology, you'd want to consider those, but for this class, on evolution, focus on the phylogenetic methods.
• it is likely that the researcher(s) have used some phylogenetic methods that we have not considered and that are not addressed in your textbook.  You can ask me about these if they seem important to you in evaluating the paper, but you are not required to address the details of any such methods in your critique.  You should be able to find enough points that we HAVE addressed in class or that ARE discussed in your textbook to write a good critique of the paper selected.