Post a composite review
Unpost a composite review
Search all MERLOT
Click here to go to your profile
Select to go to your workspace
Click here to go to your Dashboard Report
Click here to go to your Content Builder
Click here to log out
Search Terms
Enter username
Enter password
Please give at least one keyword of at least three characters for the search to work with. The more keywords you give, the better the search will work for you.
select OK to launch help window
cancel help

MERLOT II


    

Peer Review


Evolution Through Natural Selection

by The Open University
 

Ratings

Overall Rating:

4.25 stars
Content Quality: 3.75 stars
Effectiveness: 4.25 stars
Ease of Use: 4.75 stars
Reviewed: Mar 29, 2013 by Biology Editorial Board
Overview: This is an online course in the theory of evolution by natural selection, hosted by The Open University. The course is an excerpt of a longer course, which is archived (not currently being supported by the Open University), so it would not count for credit. The focus on natural selection primarily comprises a detailed exposition of Endler's experiments with guppies.
Learning Goals:
  • By biological evolution we mean that many of the organisms that inhabit the Earth today are different from those that inhabited it in the past.
  • Natural selection is one of several processes that can bring about evolution, although it can also promote stability rather than change.
  • The four propositions underlying Darwin's theory of evolution through natural selection are: (1) more individuals are produced than can survive; (2) there is therefore a struggle for existence; (3) individuals within a species show variation; and (4) offspring tend to inherit their parents’ characters.
  • The three necessary and sufficient conditions for natural selection to occur are: (1) a struggle for existence; (2) variation; and (3) inheritance.
  • Endler's experiment with guppies demonstrated that evolution through natural selection can occur in relatively few generations.
  • Mutation is the ultimate source of variation.
  • The frequency of a particular character in a particular population may be due to chance events
  • Target Student Population: Undergraduate students, including non-science majors, or lower division science majors
    Prerequisite Knowledge or Skills: Basic biology.
    Type of Material: Online course with objectives, content, and three questions with discussion answers available.
    Recommended Uses: Instructors and students could use this course to improve their own knowledge or the course could be incorporated in a class as a unit.
    Technical Requirements: Web browser.

    Evaluation and Observation

    Content Quality

    Rating: 3.75 stars
    Strengths:
  • Covers basic outline of Darwin's theory of natural selection and microevolutionary mechanisms that impact evolution.
  • Objectives clearly stated.
  • Material presented in clear, simple language.
  • Three questions concerning the example of evolution of color in guppies are proposed; discussion of answers is also available.
  • The text is well-written, concise and well-organized
  • Some images add to the course quality
  • All material is accurate
  • Background and historical context is provided
  • Concerns:
  • No history of evolution as a concept presented.
  • The social and cultural world in which Darwin's theory was developed is not mentioned.
  • Few details are given to support the points presented (eg., no discussion of role of artificial selection in development of the theory or of the events/organisms in Darwin's life that led to development of the theory.
  • Wallace"s contributions not mentioned.
  • This resource is text dense, and could use more images and subsections.
  • Additional examples beyond the guppy would improve the content.
  • Emphasis on the evolutionary context of natural selection could be more inclusive.

  • Potential Effectiveness as a Teaching Tool

    Rating: 4.25 stars
    Strengths:
    • This resource is effective in presenting the topic of natural selection.
    • The text is organized into sections and is easily searchable.
    • The writing is accessible.
    • Discussion questions are provided, with hidden responses, so students can consider the questions before reading a response.
    • Easily understood material. Presented without excessive detail.
    • Outline of objectives and summary of the material provided.
    • Figures included closely follow the textual material and support the concept well.
    Concerns:
    • This resource is text dense, and could use more images and subsections.
    • The writing relies overmuch on semi colons. Full stops would add to clarity.
    • While simplicity of presentation is a plus for high school and non-majors introductory biology, the presentation leaves out much of the detail that accompanies today's conception of evolution.

    Ease of Use for Both Students and Faculty

    Rating: 4.75 stars
    Strengths:
    • This resource is easy to use.
    • All buttons and links work, except for one.
    • The printing function works.
    • Lots of links and information is presented for other Open University courses.
    • A summary of the contents is provided at the end and a clickable Table of Contents is available in all pages of the course.
    Concerns:
    • The description of the course appears at the top of every page of the course. I figured out that I could hide this half way through, but I am not sure everyone will (the button is quite small). The course description is distracting.
    • The web page on which the course is presented is very busy, with six levels of banner buttons, a right column menu, a left column menu (TOC) and material below the course. There does not seem to be a way to view the course as a full screen page, without the other material
    • Printing retains the extraneous material (except for the right column)

    Other Issues and Comments: The discussion of natural selection is well-written and includes an extensive and detailed example of research demonstrating the characteristics of natural selection. However, some aspects of natural selection that students commonly misunderstand are not addressed. These include: 1) What level(s) natural selection acts on. This is mentioned but might be emphasized more. 2) Other mechanisms of evolution are mentioned (genetic drift and mutation) and it is noted that natural selection can promote change or stability. Why not mention gene flow, for the sake of completeness? More importantly, it is not emphasized that among the possible causes of evolution, only natural selection typically results in increasingly better adaptation of organisms to their environment.