Reviewing a high-school book in environmental science

Holt Environmental Science
1996. 432 pages. ISBN of the student's edition: 0-03-003133-8.
Holt, Rinehart and Winston, Inc., 1120 South Capital of Texas
Highway, Austin, Texas 78746. (This company is a subsidiary of
Harcourt Brace & Company, which is a part of General Cinema Corporation.)

This Gaudy Book Can Be
a Boon to Slow Students

Max G. Rodel

My initial impression of Holt Environmental Science was negative. At first I found it difficult to look at this book for more than ten minutes without tiring. The pages are confusing, almost chaotic, visual displays loaded with images, headings, boxes, logotypes, blurbs and other distractions, and the text is obscured by a head-spinning barrage of sidebars, feature articles, section reviews, "Eco-Fact" notes and "Field Activity" items. As far as design is concerned, Holt Environmental Science is an offspring of fast video games and flashy television commercials.

As I continued to browse, however, I began to warm to this book. Youngsters whose motivation and capacities are limited will love Holt Environmental Science, I believe, and I venture to say that some of them may be inspired to take some real science courses.

The book has fourteen chapters: "Environmental Science," "Living Things in Ecosystems," "How Ecosystems Work," "Kinds of Ecosystems," "Water," "Air," "Atmosphere and Climate," "Land," "Food," "Biodiversity," "Energy," "Waste," "Population Growth" and "Toward a Sustainable Future."

The introductory account of scientific methods, on pages 13 through 19, is commendable. Here we find a concise passage about the difference between pure science and applied science, followed by explanations of how scientists make observations, devise hypotheses, conduct experiments, interpret data, and share their results. I also like the way in which the writers have used, in each chapter, a pedagogic device titled the "EcoLog." The "EcoLog" is a box that presents a few questions for the student to answer, and it appears twice: The student must answer the questions before he begins the chapter, and he must answer them again when he reaches the chapter's end. In revising his answers, he applies some of the things that he has learned.

Every chapter offers an "Investigation" activity that requires students to make field observations or perform experiments that expand on information presented in the chapter. Many of these "Investigations" are impressive because they involve simple and often clever illustrations of scientific or technological ideas. Examples include the procedures for testing the effects of acid rain on plants (page 168), for measuring "global warming" in a jar (page 192) and for making a model of a passive solar dwelling (page 298). My favorite is the activity "Mining for Peanuts" (page 222). The operation of the "peanut mine" teaches some terrific lessons in environmental economics.

Many of the sidebars that have been sprinkled onto the text pages are labeled "Case Study" or "Making a Difference" or "Points of View." The "Case Study" articles offer glimpses of many different things, e.g., the Love Canal debacle ("a toxic nightmare"), the restoration of Lake Washington ("an environmental success story"), the abuse of the Ogallala aquifer, and the International Whaling Commission's wobbly efforts to control commercial whaling. The "Making a Difference" pieces introduce some individuals who supposedly have done significant work that has environmental implications. The "Points of View" pieces deal with public-policy questions that involve environmental affairs.

There are other articles as well, placed at the back of the book. These include some "Environmental Careers" sketches and a collection of "EcoSkills" pieces that provide instructions for projects. The projects -- such as making a compost heap, planting a wildlife garden, or constructing a bat house -- are reminiscent of a child's fun-with-nature guide rather than a science text, but they are entertaining and, in their own simple way, instructive.

The good elements of Holt Environmental Science are offset by some serious difficulties. Because the pages are so heavily loaded up with pictures, sidebars and ornaments, the coverage of scientific topics seldom achieves any depth. Most matters are handled superficially, and some of the material smacks of alarmism.

A note "To the Student," at the front of the book, promises that the student "will learn about the complex issues facing our environment," will encounter various points of view and differing opinions, and will acquire a growing ability to draw his own conclusions. It is true that the book presents different points of view about solutions to environmental problems, but -- in my judgment -- the presentations are not always even-handed. Overall, it seems to me, an activist and liberal predilection prevails.

On page 146, as an example, a laboratory exercise is introduced by the headline "How Safe Is Our Groundwater?" I like the exercise, in which the student filters dirty water through soil, but I notice that it does nothing to answer the question posed in the headline. The headline doesn't seem to have any function except to suggest some kind of threat. The exercise doesn't present any information about natural groundwater, and it doesn't provide any basis for assessing the safety of groundwater supplies.

On page 202 there is the customary and politically correct plug for urban mass transit: "Mass transit is an economical, efficient alternative to the automobile," the writers say. But for most people in the United States, mass transit is neither economical nor efficient, and that is why so many people continue to use private automobiles. Holt's book does not consider this important matter in any realistic way.

Another lopsided passage is the short section, on page 282, titled "Dwindling Supplies of Fossil Fuels." Here the writers state that "Fossil fuel supplies are limited, and we are using these resources much faster than they can be replaced by nature." That intuitive statement is not supported by facts, and we have no understanding of the rate at which nature may be creating new stocks of, say, petroleum or natural gas. The known reserves of fossil fuels increase every year, as more stocks are discovered, yet Holt's book tells the student that fossil-fuel supplies are "dwindling."

Alarmism and distortion aside, some of the material in Holt Environmental Science is so superficial that it contains no science and can be misleading. An example is the feature article on pages 148 and 149, titled "High School Chemist." A high-school girl supposedly has discovered that she can remove "toxic trace metals" (lead, mercury, cadmium and chromium) from tap water by treating the water with living yeast cells. This so-called breakthrough allegedly developed from her speculation that "there was probably some sort of living organism that could remove heavy metals." The breakthrough, however, may be imaginary. We don't see any data to show that heavy-metal concentrations really decline when the water is treated, and we are asked to accept on faith the claim that the girl's technique depends upon "living organisms." To me, the illustration accompanying the text suggests that her procedure merely involves the adsorption of metals onto the surfaces of yeast cells -- cells that probably are dead. (Such adsorption is a well known phenomenon, discovered long ago.) The article doesn't qualify as an exposition of science, and it can only mislead idealistic youngsters.

Even with its flaws, however, Holt Environmental Science can be a boon to some students, i.e., those who are poorly motivated and poorly prepared to study science. I think that such students will like this primer for environmental activists, will enjoy its splashy style, and will respond to its emphasis on matters that are relevant to daily life. The book is light on real, hard-core science, but it is generally effective in demonstrating scientific methods, and it may help the students to see that science can be fun. For this reason, it may be useful not only in certain high-school classes but in some middle-school classes as well.

This Isn't a Science Book,
but It Has Good Pictures

William J. Bennetta

Holt Environmental Science is a garish and tacky creation, and my first tour through its pages left me disgusted. Let me explain this by summarizing my initial observations and judgments:

• Though it is promoted for use in high schools, and though it has "science" in its title, Holt Environmental Science cannot be regarded as a high-school science book in any customary sense. Its scientific content is scanty at best, and I cannot imagine that the book would be of any use to high-school students who really want to learn science. It mentions scores of scientific topics, in scores of red headlines, but the paragraphs of text under the headlines are typically so short, vague and fluffy that they amount to nothing more than sloganeering. Many natural phenomena are listed and dismissed without the explanation or exemplification that might give them some meaning, scores of terms are used without definition, and straightforward concepts (such as the reason why Earth has seasons) are compressed until they become mysteries. Moreover, some passages are just ludicrous. Read, for example, the tiny passage headlined "Coral Reefs," which contains a wee paragraph marked "Animal Adaptations." Here the writers cite exactly one adaptation of one coral-reef animal, stating that "The remarkable parrotfish has beaklike teeth that it uses to scrape algae and corals off reefs to eat." Even if the statement were correct, the paragraph would be laughable. To inflict this book on capable, curious high-school students would be a shame.

• Along with its errors of fact, the book shows various conceptual mistakes. When, for example, the writers dash through the topic of "Tropical Rain Forests," they create nonsense by confusing growth rates (of plants) with species diversity. In writing about "Ranching," they forget their own definition of "desert," and they use "desert" as if it were a synonym for wasteland. Their two-paragraph treatise on "Predation" includes a blazing non sequitur (namely, the claim that predators often "have little effect on the numbers of their prey because they tend to feed on whatever prey species is abundant at the time") and an obvious absurdity (the claim that predators "tend to feed on old and weak individuals who are more likely to die soon anyway").

• To the extent that the Holt writers touch upon the interactions between humans and the rest of nature -- interactions which are, after all, central concerns of environmental science -- they offer a perspective that is painfully obsolete. Instead of using overpopulation as a unifying theme, they relegate it to the book's penultimate chapter, and they fail to describe any birth-control techniques or population-control programs. (There is an allusion to China's program, on page 353, but it is vague and misleading.) Writing a book about environmental affairs without telling about birth-control methods and population-management strategies is akin to writing a book about public health without telling about vaccines and clean-water technology.

• One reason why this book has so little text and so little content is that its pages are overloaded with illustrations and eccentric graphics and eye-catching gewgaws. Holt Environmental Science is a TV textbook if ever there was one. Indeed, a lot of the spreads in this book -- and a lot of the individual pages, for that matter -- seem to be discrete visual packages that could be displayed effectively on a TV screen. As a whole, Holt Environmental Science is a book of flash and dash, apparently reflecting the principle that nobody should have to follow an idea or hold a thought for more than a minute or two.

• It seems clear that the people who assembled Holt Environmental Science were not trying to produce a book that anyone would actually read. Rather, they seem to have wanted a book that would be suitable for casual, even random, browsing -- call it surfing, if you like. Perhaps the best indication of this is the repeated occurrence of margin-notes that advertise topics that will show up later in the book. If you try to read the text on page 57, for example, you'll be distracted by a colorful note that tells what you'll find on pages 76 and 77; if you try to read page 67, you'll run into a note that hypes a topic on pages 374 and 375; if you try to read page 99, you'll find a plug for a topic that will appear on pages 118 and 119; and so on. These useless, distracting items are obvious hindrances to concentration, and they tell me that Holt's people did not design this book for anyone who might try to concentrate on anything.

• The book does offer some respectable discussions, but these are presented in sidebars -- not in the main text. The reason for this eludes me. Perhaps it bespeaks another attempt to imitate TV. Perhaps the main text is supposed to correspond to the fluffy shows that one finds on commercial channels, while the sidebars represent the informative programs that are broadcast by PBS stations. In any case, some of the sidebars are good. Examples include the "Butterfly Ecologist" profile (page 52) and the articles about fires in Yellowstone National Park (page 68), the Ogallala Aquifer (page 126) and whooping cranes (page 256). On the other hand, the "Points of View" sidebars, which supposedly tell about current political disputes, are mostly worthless. Holt's writers merely recite the disputants' assertions, telling us that these guys say this while those guys say that. Maybe, but these guys or those guys (or all the guys) may be badly deluded or may be telling lies. Holt's writers seem not to know this; they fail to explain out that some of the assertions which are recited in the "Points of View" sidebars are patently false or absurd. Brainless parrot-work may be acceptable on a TV news show, but it is not acceptable in a schoolbook that has "science" in its title.

Those were my initial opinions, and I still hold them. I think that Holt Environmental Science is schlock and is unfit for use in a real science class.

In looking through it again, however, I have come to think that it may be helpful in a less rigorous setting: This flashy picture-book seems suitable for putting a modicum of science (or at least some awareness of natural processes) into the heads of those students who have been so badly damaged by television that they cannot handle much reading. To be sure, Holt Environmental Science has its share of pictures that are merely decorative, but it also has plenty of pictures that can convey meaningful facts and ideas to poor students. In fact, I judge that the book's illustrations, all in all, are noticeably more reliable and more useful than the text. I would rather see slow high-school students using Holt Environmental Science than using some middle-school book that has no merit whatsoever.

Max G. Rodel is an environmental chemist, a registered environmental assessor in California, and a senior scientist with Environmental Science Associates, a consulting firm in San Francisco.

William J. Bennetta is a professional editor, a fellow of the California Academy of Sciences, the president of The Textbook League, and the editor of The Textbook Letter.

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