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Fundamentals of Molecular Evolution, 2nd ed.
Dan Graur and Wen-Hsiung Li. Sinauer Associates, Inc., Sunderland, Mass., 1999, $48.95 (paperback).
A book can evolve, by processes somewhat similar to those governing biological molecules. This second edition of Fundamentals of Molecular Evolution has grown from 284 pages in the 1990 edition to the current length of 478 pages. However, there are questions of book cloning as well as evolution. Once word processors colonized the publishing environment, new editions became heavily dependent on horizontal text transfer. Whether this is a second edition of the first depends on how you look at the book Molecular Evolution (1997) by Wen-Hsiung Li (487 pages), from the same publisher, and with basically the same listing of chapter titles and subtopics. To this reviewer, this is a repackaging of the 1997 volume, with minor updating. Figures, sentences, and more importantly the ideas have mostly not been revised. This is especially a problem because new science has led to new understanding.
Molecular phylogenetics is a subject that has exploded in new understanding during the last decade. Much of what is new is not here. Genomics (chapter 8 here; chapter 13 in the 1997 volume) has an attempt at updating. After all, the first (microbial) genome appeared in 1995, but eukaryote genomes are too new to have been analyzed: yeast (1997) is on the cover but really not handled. The worm genome (1998) is not mentioned, and the fly genome, which is just now complete, was not anticipated. The human genome is described more as expected for a 1997 or earlier book. These criticisms concern central questions of contemporary molecular evolution.
With that said, this is still a well-written, easy-to-read text, suitable for upper undergraduate-level courses that are mostly concerned with higher animals, with little or no microbiology. The writing is direct and fluid--comfortable phrasing and not excessively technical. The title Molecular Evolution, however, gave an expectation that major topics of interest to readers of ASM News would be considered in depth. These might include the first cell, molecular evolution between that cell and the last universal ancestor of currently existing cellular organisms, the extraordinary diversity of prokaryotes (both bacteria and archaea) and unicellular eukaryotes, and how massive horizontal movement of genes occurred early in evolution. That plants, fungi, and animals are ``mere twigs on one branch'' when one tries to relate all living organisms phylogenetically is important. Current organisms called ``protozoa'' are not unicellular animals (as was once thought) but are indeed deeply rooted ancient organisms of different origins. All these are large questions missing from the current book. Perhaps a third edition around 2010 will fix some problems. However, for this hope the authors need a much more thoughtful input of molecular microbial evolution. Instead, we are warned (for example in Chapter 5) of the importance of morphology and anatomy (with fossil records) in understanding phylogeny and told explicitly that use of DNA sequences ``to resolve . . . longstanding problems of phylogenetics . . . and evolutionary relationships among bacteria and unicellular eukaryotes (will be) in the future.'' Sorry, folks: the future has been here for a while. Contrary to the authors' contention (on p. 4) that Monod's famous ``Ce qui est vrai E. coli est vrai pour l'elephant'' was wrong, the population structure of Salmonella and Escherichia coli has more to teach us about molecular evolution of life forms than does the detailed description of population structures of sparrows, rodents, zebra and whales, as given here.
This is not a complaint that the authors have emphasized their own interests. It is rather that essential aspects of molecular evolution are either missing or treated superficially. As written, the volume appears too much like the population genetics of half a century ago with a shallow veneer of molecular tools. Archaea do not appear in the subject index, although an out-of-date early Woese picture (Fig. 5.39) with Archaea does appear briefly in chapter 5. There is much more (too much) emphasis on how to generate trees and evaluate their mathematical reliability, and less on how current trees reflect phylogenetic lineages.
Simon Silver
University of Illinois College of Medicine, Chicago
EDUCATIONAL MATERIALS
AIDS: A Biological Perspective
VHS videotape. Published by Cambridge Research Group, Ltd. &
Black Bear, 1995.
Available from Films for the Humanities & Sciences, Princeton, N.J.,
[(800) 257-5126, http://www.films.com
], $49.95.
Target Audience and Purpose:
AIDS: A Biological Perspective addresses a general adult audience to deliver an overview of HIV and AIDS. Its presentation mode is more conversational than pedagogical.
Description: This 30-minute color video begins with the faces and voices of everyday American adults infected with HIV, who help correct the early misconceptions about HIV/AIDS. Scientific experts explain the nature of viruses and HIV in particular, as well as drug treatment and prospects for vaccine. AIDS Task Force workers delineate the epidemiology of the epidemic: who got infected at what time in the U.S. Several sources paint a picture of AIDS as a disease. Vaccines and new drugs are listed as grounds for future hope, but prevention measures are only briefly mentioned.
Level of Presentation: No specific background knowledge of biology or microbiology is assumed so that precollege audiences could follow and understand the topics.
Strengths and Weaknesses: The major strength of this video is that it convincingly portrays AIDS as a disease that is not restricted to gay men. It provides many facts about the nature of the disease, the virus, and its transmission. However, it has several flaws. There is no description of drugs other than reverse transcriptase inhibitors and no mention of viral load, T-cell counts, and the basis for HIV testing. The global aspects of the epidemic are ignored. Also, teenagers are not among the cast, which leaves out an important target group for AIDS education programs.
Recommendations: This video is not sufficiently detailed and does not possess enough clarity to stand alone, but it could serve as one tool within a comprehensive AIDS education program. It would be best used to introduce the topic of HIV/AIDS to a general adult audience, if an update is also provided. The video is not as informative about the biology of AIDS as its title would imply, and thus would be of limited use in a college biology or microbiology course.
Charlotte Mulvihill
Oklahoma City Community College
Oklahoma City, Okla.
The Emerging Viruses
VHS videotape. Films for the Humanities & Sciences. Princeton, NJ
[(800) 257-5126,
http://www.films.com ], 1998, $149
(includes public performance rights to show in educational settings).
Target Audience and Purpose:
The Emerging Viruses appears to be targeted to a general population of viewers with a high school education who are interested in science and biology. The video is appropriate for high school biology classes and nonmajor biology classes at the undergraduate level. It may be useful in higher-grade health classes, as well. The video would also be appropriate for science education in the general public. If used appropriately, it could be used as an introduction to a more detailed discussion of emerging viruses for classes in microbiology, infectious diseases, or public health. The video not only uses effective visual techniques but also takes complex issues of emerging diseases and explains them in a coherent way for the targeted populations.
Description: The video begins with an eye-catching scenario where an unknown virus is brought into a Centers for Disease Control and Prevention lab and initially handled as any other unknown agent. Soon the investigator realizes that this is not just any agent but something quite dangerous. The EM picture shows us an Ebola-like virus, which it indeed turns out to be. The video then discusses, with excellent pictures, some history of infectious diseases, including transmission of yellow fever, an excellent series of pictures on smallpox and the eradication program and an interesting scenario of dengue fever virus being spread by importation of tires. The scene then shifts to research activities during World War II. There is a very interesting section related to the discovery of penicillin that is concluded with a discussion about the ineffectiveness of antibacterial antibiotics against viruses. Of course, the entire subject of emerging viruses was brought to the fore by the AIDS epidemic. The discussion of HIV and its probable association with simian immunodeficiency virus is detailed in such a way that most people will understand some rather complex concepts. The discussion of RNA viral mutations and nucleic acid sequencing is well worth the viewing. The video ends with the discussion of an important concept not readily obvious to the general public, i.e., that emerging viruses are not new! They have existed in their reservoir for decades and often centuries. It is most likely our disruption of their reservoir by increasing population and urbanization and the concomitant introduction of worldwide travel that has resulted in their spread to different reservoirs and populations.
Strengths/Weaknesses: The video was originally taped by BBC-Worldwide Production. There is an occasional use of British terms such as ``naught'' for ``zero.'' This may be confusing to the American ear. Although the video sequence on antibiotics is interesting, it is almost out of place to the story line, based on the length of this section. The purpose of this segment is apparently to show that antibacterial antibiotics do not work against viruses. However, it is so educational for the target audience that I would hate to see it cut. The use of so many experts in the field is a real positive aspect of the video.
Recommendations: The Emerging Viruses is an extremely worthwhile video that can be used under a variety of circumstances. The information provided is accurate and the visuals are of the highest quality. The video is highly recommended for general scientific viewing.
Jere M. Boyer
Summa Health System
Akron, Ohio
WEB SITE
Science in the Real World: Microbes in Action
The target audience of the Science in the Real World: Microbes in Action Web site is elementary and high school teachers looking for ways to promote an understanding and appreciation of the importance of microorganisms in their classrooms.
The Microbes in Action Web site highlights the activities of a precollege microbiology education program that resulted from a collaboration of scientists from the University of Missouri at St. Louis and from industry, teachers, and a specialist in curriculum development. The program has four components: (i) summer and academic year workshops for teachers that focus on hands-on activities in microbiology appropriate for the high school classroom; (ii) activities that introduce a broad range of microbiology techniques to students from grades 3-12; (iii) short articles on microorganisms; and (iv) techniques and troubleshooting articles that help teachers to be successful using microorganisms in the classroom. In addition, the Web site includes links to a variety of resources in microbiology for teachers and students.
The materials and resources available on this site are intended to engage the interest of students with a broad spectrum of interests and abilities by presenting microbiology with a real-world focus. The activities include the production of carbon dioxide by yeast, effectiveness of disinfectants, microbial staining, microbial isolation and culturing, micropipetting, and counting coliform bacteria in a water sample. The activities are described in a detailed, simple step-by-step format, and most can be done with simple and inexpensive equipment and supplies. The articles are short readable digests of ``hot news'' topics, such as microbes in the Antarctic, anthrax as an agent of biological warfare, and the microbiological basis of ulcers. The news articles and activities are provided as Adobe Acrobat files that can be downloaded and printed for use in the classroom.
Overall, this site offers an interesting variety of teaching activities intended to increase student interest in microbiology, and presented in a practical and accessible format. This site provides a rich source of approaches to introducing younger students to the role microorganisms play in the world. The Microbes in Action Web site is supported by grants from the National Science Foundation, The Foundation for Microbiology, Pfizer Foundation, Sigma Aldrich, and Eisenhower Act funds administered through the state of Missouri.
Kristin Connarn
Judith E. Miller
Worcester Polytechnic Institute
Worcester, Mass.
Email: webmaster@asmusa.org