Reviewing a middle-school book in life science

A Bogus Book That Is Unfit
for Any Science Classroom

Ellen C. Weaver

Addison-Wesley's writers completely conceal the evolutionary basis of taxonomy. They are silent about the powerful evidence that tells of relationships among organisms. They shun dozens of opportunities to show how evolutionary insights unite taxonomy, genetics, ecology and other biological disciplines into a single, coherent science. They depict evolution itself as an idiosyncratic notion left over from the 19th century. And when they give fleeting acknowledgment to the idea that life on Earth has a history, they take pains to depict our understanding of that history as idle conjecture. In short, they present the living world in a way that has nothing to do with science but has everything to do with fundamentalism.

Along with its sectarian religious viewpoint, Addison-Wesley's book shows at least three more traits that make it unfit for use in any science class:

• It has many blatant, basic errors: statements whose falsity will be obvious to anyone who has taken introductory science courses, and has studied from competent textbooks, as a college freshman.

• The content is intolerably unbalanced. Of the book's 598 pages, some 130 are given to one species -- Homo sapiens -- while entire classes, such as the insects or the fishes or the birds, get two to four pages apiece. How wrong! How cheated must any student feel who is interested in those wonderful groups of animals and who has been hoping to learn more about them from a "life science" book!

• The writers use a style suggesting that students must be witless dolts. Here is a passage from page 438:

  The young are like their parents in many ways. For example, puppies always look like small dogs. Kittens always look like small cats. But within each litter there are some variations. Some puppies may open their eyes before others. Some may grow faster. Some may have floppy ears. Some may have bigger feet. Some may. . . .

  Does that recall Dick and Jane and "Run, Spot, run"? Not all of the writing in the book is as bad as the puppy passage, but most of it is childish and dull.

theory of evolution by natural selection -- The idea proposed by Charles Darwin that organisms have changed gradually over a long period of time. Darwin believed that helpful variations developed by chance, but that individuals with these variations were then more likely to survive to bear young and thus pass on the variation.

That is false and grossly misleading. The idea that organisms have changed over time -- that they have undergone evolution -- did not originate with Darwin, is not unique to Darwin, and is not the same as the idea of natural selection. Evolution is change: nothing more, nothing less. Natural selection is one concept that explains the change. And it is evolution, not natural selection, that unites all of today's biology. Addison-Wesley's writers misrepresent and confuse two different things, and they fail to acknowledge evolution in its own right.

They repeat their performance on page 438 of the text (which provides some expansion of the defective item in the glossary), and they again mislead the student. They allocate about as much space to Lamarck's ideas as to Darwin's, and they say that Weismann's famous tail-cutting experiment showed that Lamarck was wrong; but Weismann's work did no such thing. Most conspicuously, the writers again cast evolution as the idea of one man, Darwin, who died more than a century ago. They say nothing about the modern status of evolutionary biology. There is no discussion of homologous structures in the vertebrates, nothing about the overwhelming biochemical evidence that all living things share a common ancestor, and not a single word about human ancestry. There is not even an exposition of affinities among the primates.

Lest students get an idea that evolution is something that actually has gone on, the writers ignore, misrepresent or explicitly disparage the compelling evidence supplied by fossils. On page 430 we find an abbreviated chart of "The Eras of Geologic Time," but there is no meaningful text -- none! -- about the pageant of life that unfolded during those eras. On page 432 we read that "Fossil evidence suggests that for millions of years giant dinosaurs lived on earth." Suggests? If the great dinosaurs are mere suggestions, what can all those bones be?

The misrepresentations continue: "The fossil record suggests that many kinds of organisms that once lived are no longer on earth. . . . It is believed that the continents have not always been their present distances from the equator. . . ." Suggests? Is believed? There is not one line about the abundant evidence of continental drift, or of the consequences of continental drift to the distribution of living things.

Addison-Wesley Life Science is the sort of bogus book that cannot be adopted in California, now that California's newest Science Framework is in force. Page 125 of the framework states:

The unifying theory of biology is evolution; as [the geneticist] Theodosius Dobzhansky said, nothing in biology makes sense without it. It is accepted scientific fact, and has been since the mid-1800s, that organisms are descended with modification from other organisms. . . . The classification of organisms -- indeed all of comparative biology -- is based on evolution. Curricula must reflect this centrality of evolution in the biological sciences.

• On page 19: "Any compound made of molecules containing carbon is called an organic compound." The writers are unfamiliar with basic chemistry. Compounds such as carbon dioxide, carbonic acid and calcium carbonate -- all of which have great biological importance -- are inorganics.

• On page 81 the writers' "explanation" of chromosomes and nucleic acids is a hopeless mess.

• Page 82 says that agar is "rich in protein and other important compounds needed for growth [of bacterial." But as introductory books on bacteriology tell, agar is a polysaccharide; to say that a polysaccharide is rich in protein" is absurd. Moreover, one reason why agar is so useful in the bacteriological laboratory is that, by itself, it does not support the growth of heterotrophic organisms. Addison-Wesley's writers have got things exactly wrong.

• On page 116: "The second part of a scientific name is the name of the species." No. The second part is just an adjective that, by itself, is not the name of anything.

• On page 160 the writers tell the student to do library research on red snow, "which involves red algae." The writers should have done some library work of their own, instead of guessing. Red snow is caused by one of the green algae.

• Page 199 says that the staminate flowers and the pistillate flowers of plums grow on different trees. This too is quite wrong. Some tree species (such as carob) show such an arrangement, but plums do not.

• On page 181: "The roots of most dicots are long, slender and only slightly branched." The dicots shown in the accompanying picture are radish, beet and carrot -- cultivated plants that have been selected for large tap roots. They are not representative dicots, and the whole business is misleading.

• On page 183, a picture purports to show sections through the stem of a woody plant and the stem of an herb, but the drawing labeled "herb" really shows the stem of a monocot. The caption asks: "Is there more vascular tissue in a woody plant or in an herb?" Given the mislabeled picture, that question is meaningless. Moreover, the picture lacks any indication of the size or scale of the objects shown.

• On page 400 a picture allegedly shows meiosis, but I doubt that such a process has ever been seen under a microscope. It presumably was guessed into existence by an artist who thought that it looked good. It is not the way in which diploid cells give rise to haploid ones.

One must hope Addison-Wesley Life Science will fail badly in the marketplace. If educators will accord this book the scorn that it deserves, the publisher may be motivated to replace it with a science book.

A Sorely Incompetent Book
That Is Not Recommended

David R. Stronck

Because of recent curriculum-reform efforts, the state of California will no longer adopt any life-science book that fails to promote higher-order thinking skills or fails to provide legitimate treatment of sex and of organic evolution. Addison-Wesley Life Science fails on all counts. It clearly would not be acceptable in California, nor can I recommend it for use anywhere else.

Besides evading the subject of sex and misrepresenting the subject of evolution, Addison-Wesley's writers generally present information as something to be memorized, rather than understood. They fail to relate that information to scientific research, they fail to invite students to think, they reduce various topics to incomprehensibility, and they present many statements that are distortions or plain errors.

As an example of the writers' giving information for blind memorization, without explaining it or telling of its basis in research, here is a passage from page 17:

All the elements are shown on a chart called the periodic table. They are arranged according to their atomic number. This number tells how many of a certain kind of very tiny particle [?] is inside each atom of an element. Each element also has an atomic mass number, which is a measurement of the average mass of one atom of the element.

As far as I know, none of the terms introduced in that passage is ever used again. The book never again says anything about atomic numbers, atomic mass or periodic tables. Why should students have to memorize such meaningless prose? This is one of many cases m which the writers seem to pad their book with empty mentionings that will bewilder and discourage students.

On page 429 we read that the trilobites existed for only "a short time" and "were not on earth for long" before they became extinct In fact the trilobites entered the fossil record 570 million years ago and persisted for 315 million years -- more than half of all the time that has elapsed since the first hard-bodied animals appeared. For at least 80 million years, they constituted the most common and diverse group of animals that left fossils. How can Addison-Wesley's writers imagine that the trilobites "were not on earth for long"?

For incomprehensibility, try page 174 and a passage that purports to tell seventh-graders about alternation of generations in gymnosperms:

The familiar tree or bush is the spore-producing plant although the spores it makes always remain within the cones. This part of the life cycle is easy to see. The other stage is very hard to see. The generation that produces eggs and sperm forms inside the cones. The egg-producing stage is found inside the ovule on female cones. The sperm-producing stage occurs within the pollen grain.

How could a seventh-grader understand that? There is no picture or further text to help with comprehension -- not even an explanation of why spore-production, occurring within cones, is easy to see, while egg-production or sperm-production, occurring within cones, is hard to see.

On page 143 the writers present slime molds as "the eighth phylum of protists." That is questionable; specialists such as O'Neil Ray Collins and Donald Betterley think that slime molds (and other myxomycetes) are allied more closely to animals than to protists. What is not questionable is that the life cycle of slime molds has three principal stages. Addison-Wesley's writers, however, imagine that it has only two.

In this book, the vagina is solely "a passageway that serves as the birth canal." The penis is mentioned but seems to have no function. It is just something through which sperm cells pass as they are "exiting the urethra." The writers' aversion to the penis is reflected in the nearby picture, which depicts only the "internal organs of the male reproductive system," not the system as a whole. Yet the picture shows the testes, even though the text says that testes lie "outside the abdomen in a protective sac." How can "internal organs" be "outside"?

The book's handling of AIDS is vague. The term AIDS is not found in the index or the glossary, though AIDS is mentioned three times in Chapter 8, "Defending the Healthy Body." A chart in that chapter says that, for prevention of AIDS, one should "Avoid exchange of body fluids with infected persons." That is inadequate and confusing; "body fluids" could include sweat and other fluids that currently are regarded as harmless. The book should say: Avoid sexual intercourse with, or blood from, infected persons. (And it should, of course, tell what sexual intercourse means.)

A recent survey by the National School Boards Association showed that some 80% of the schools in the United States now furnish students with information about AIDS, and that such information is most commonly inserted into courses given in grade 7. Addison-Wesley Life Science is certainly inadequate for any such purpose.

The "classification" offered in Addison-Wesley Life Science absolutely excludes any evolutionary perspective. It absolutely excludes today's science.

Much the same can be said of the book as a whole. The writers rigorously avoid the concept that should be the book's grand theme, and they even fail to define the word evolution. Both the glossary and the index falsely equate evolution with theory of evolution by natural selection. The text does the same thing, and it falsely treats both evolution and natural selection as old ideas, originated by Darwin, that apparently have no modern significance.

The brief discussion of "Darwin's theory" is in chapter 11, "Organisms in the Past and Present." The chapter opens with a vague, unfathomable section about fossils. There is no attempt to tell how the ages of fossils are determined, and the picture captions do not tell the ages of any of the fossils that are shown.

This is followed by a section called "Time and Change," in which the writers relegate the history of life and the history of Earth to some equivocal hints and distortions. On page 433, for example: "The fossil record suggests that many kinds of organisms that once lived are no longer on earth." In fact, the fossil record indisputably shows that Earth once supported organisms that now are extinct; this was established some 200 years ago by Cuvier (1769-1832). The writers' expression "suggests" is wrong and misleading.

On the same page: "It is believed that the continents have not always been their present distances from the equator. . . ." Is there any evidence for that idea? The writers do not say. They lead the student to think that continental drift -- a richly confirmed principle and one of the most potent explanatory ideas in paleontology and biogeography -- is just a notion that, for no cognizable reason, "is believed." That is no way to write a science book.

Ellen C. Weaver is a professor of biological sciences, emerita, from San Jose State University. Her scientific specialties are plant physiology and the application of remote sensing to the oceans, and she has served as an advisor to the National Academy of Sciences. She is an elected fellow of the American Association for the Advancement of Science and a past president of the Association for Women in Science.

David R. Stronck, a specialist in science education and in health education, is a professor in the Department of Teacher Education at California State University, Hayward.

Addendum

The "authors" shown on the title page of Addison-Wesley Life Science are two professors -- Bonnie B. Barr and Michael B. Leyden. Did Barr and Leyden really participate in the creation of Addison-Wesley Life Science? Have these "authors" ever seen the book that they allegedly wrote? To learn how they responded to our written inquiries, please read "Still No Answer from Either One."

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