Reviewing a middle-school book in life science

Evading Basic Information
and Confusing the Student

Michael T. Ghiselin

This book is trash. Students who begin in ignorance will end not only ignorant but confused and misinformed as well. We cannot say that the Silver, Burdett writers have failed to follow the rules. Quite the contrary. They have done what the writers of life-science books have been doing for many years now: They have produced a tedious list of things to he memorized, and they have decorated it with some entertaining curiosities, while only pretending to give attention to unifying concepts.

In chapter 2, about classification, the writers conceal the fact that the basis of classification is common ancestry. The student reads that organisms are linked taxonomically if they share traits and are "closely related," but "related" is left undefined and there is no explanation of why some traits matter and others do not. In short, there is no evolutionary perspective whatsoever.

The writers do not introduce evolution (or "change," as they call it) until chapter 16, where they again fail to make explicit the connection between evolution and classification. Indeed, the idea of common ancestry is artlessly replaced by the idea of change through time, which is, of course, only part of it.

In surveying the animals, the writers place those organisms in a linear sequence -- "simple" ones first, "complex" ones later -- following an ancient tradition that was demolished by Karl Ernst von Baer and Georges Cuvier in the 1820s and has had no intellectual respectability ever since. The only place where we find anything resembling a phylogenetic tree is in Appendix 1, where a "Taxonomy Tree" tells us that sharks are related more closely to tigers than to penguins! The writers seem to imagine that sharks and tigers possess some close affinity because both sharks and tigers can be big and fierce, but that is not how taxonomists classify things.

One form of "dumbing down" that I find particularly disconcerting is the pointless substitution of vernacular words and made-up phrases for legitimate technical expressions. Silver Burdett & Ginn Life Science does this in several ways. In some cases, the writers use an anglicized form of a technical term while avoiding the term itself: Thus they teach the student the words arthropod and mollusk but not the formal names Arthropoda and Mollusca. In other cases, scientific words are gratuitously replaced by cumbersome phrases. Snails and their allies, for example, are labeled the "stomach-footed mollusks," instead of being called the Gastropoda (or even the gastropods); and the student gets the false impression that "stomach-footed mollusks" is a term used by scientists. Even worse, the writers invent and name groups of organisms that are wholly fictitious: Such groups as the "Simple Invertebrates," the "Complex Invertebrates" and the "Warm-Blooded Vertebrates," for example, are quite unknown to science.

The sections about diversity are not adequately integrated with the rest of the text, and there is so much repetition of material that the text seems to have been written by a committee that never met. Nor is it merely chaotic and confusing. It is also boring and unimaginative. Consider a definition that appears on page 492 (and has already appeared in at least one other life-science book): Purporting to tell about human reproductive systems, the writers define the penis as "the male organ through which semen passes to the outside of the body." A young reader, and especially one who has had some hands-on experience with the organ in question, may well wonder why the writers do not tell about what comes before and after that.

The book does have a lot of material about sex and reproduction, but much of it is grossly misleading or downright wrong. On page 222: "Many invertebrates can reproduce by both asexual and sexual means. Asexual reproduction involves only one parent. In sexual reproduction a sperm and an egg join to produce a new individual" (italics in the original). The last two sentences, incongruous as they are, tell us that the writers think that a sperm and an egg necessarily come from two different parents. That is false. When a hermaphroditic animal fertilizes itself, each offspring arises from the joining of a sperm and an egg but has only one parent. Perhaps we should not be surprised that the writers are so confused, for they seem not to know that hermaphroditism is a widespread and important phenomenon among animals. It does not appear anywhere in their book.

On page 331 the writers define regeneration as "a type of asexual reproduction in which a new organism can grow from a body part." That is flatly wrong. Regeneration is not a form of reproduction at all. Lizards regenerate lost tails (and crabs and starfishes and salamanders regenerate lost limbs, and humans regenerate damaged livers), but they are not reproducing when they do so. To make things worse, the writers assert that asexual reproduction "occurs" in "simple animals, protists, and monerans," and they provide an illustration labeled "Regeneration in a starfish." But a starfish is not a moneran, a protist or even (according to this book) a simple animal. In Silver, Burdett's bizarre taxonomy, echinoderms are explicitly "complex."

I repeat: This book is trash.

Dispensing Phony "Science"
and a Contempt for Nature

William J. Bennetta

The great variety of animal life has long been a source of wonder and delight for many people. There are over a million different kinds of animals on the earth. Some are quite familiar to you. Others are rare and unusual. The Loch Ness monster and the abominable snowman are animals whose existence has not yet been proven. In this unit you will study major groups of animals and see how they are alike and how they differ.

Notice two points. First, the paragraph does not name any real organism but cites two creatures from the realm of fable. Second, it clearly conveys the idea that those fabulous creatures exist, and so deserve to be called "animals" in a scientific context, even if evidence of their existence has "not yet" shown up. Silver, Burdett's writers apparently think that "science" is the business of believing attractive stories -- and evidence be damned.

That notion pervades Silver Burdett & Ginn Life Science thoroughly. This is not a book of science but a book of credulity and buffoonery, reflecting all the practices that the publishers of worthless "life science" books have been following for years. Foremost among these, surely, is the use of writers who are abysmally ignorant of the subject matter. As soon as we start reading, we see that Silver, Burdett's text is wrong, wrong, wrong. We see also that the writers are recycling stale nonsense and fantasies -- stuff they presumably have copied from other schoolbooks that were devised by other ignoramuses. Chapter 1, for instance, has the usual rubbish about the scientific method: It tells students that all science consists of controlled experiments, performed according to a simple-minded recipe. That story was silly on the day when it was dreamed up and is silly still -- regardless of how often it has been copied and recopied by schoolbook-company buffoons. Chapter 2 purports to be about classification. It is more rubbish. Nowhere do I find a coherent expression of the principle that classification is historical, that its guiding concept is organic evolution, and that its aim is to reconstruct genealogies.

What bothers me most about Silver, Burdett's text, however, is not that it is ignorant but that it is phony and pernicious.

As far as I can tell, this book and the others like it share one grand objective -- to equip students with a contempt for nature as a whole and especially for anything that is alive but not human. If that is indeed the goal, we need not be surprised that these books are the way they are. They pretend to describe nature and science, but they are built around anthropocentric superstitions that contravene nature and will ruin anyone's efforts to learn or teach science.

One of those superstitions to which I refer forms the axis of Silver Burdett & Ginn Life Science, for this book is devoted to the old idea of "nature's ladder" -- the notion that Earth's organisms constituted a single, continuous series, from very "low" and "simple" ones to "high" and "complex" ones. Each organism's place on the ladder, along with its presumed importance in nature, depended on how closely the organism seemed to resemble the "highest" creature of all -- the adult, male, European human (or AMEH, as we may call him).

Science discarded that notion in the early 19th century, because it clearly was wrong, but Silver, Burdett's writers are still promoting it. Hence chapter 10 is about "Simple Invertebrates" (including such organisms as octopuses!) while chapter 11 is about "Complex Invertebrates" (including insects and starfishes). The writers do not say what "simple" or "complex" means, and with good reason: As descriptors of animals, those terms have no meaning at all -- nor is there any way to show that an insect is "complex" but an octopus is not. Silver, Burdett's stuff is pure superstition.

Moving up Silver, Burdett's ladder we find a rung that bears both the agnathans (fancifully labeled as "jawless fishes") and the cartilaginous fishes. The lumping of these two classes falsely implies that they are comparably primitive. Each class gets one page. Each is apparently incapable of reproduction, for the writers say nothing about how agnathans or cartilaginous fishes may perform that function. (I am ignoring an introductory passage on "Traits of Fish," on pages 274 and 275. It is so stupid that I cannot tell to which class, if any, its nonsense is supposed to apply.)

On the next rung are the bony fishes. These too are apparently incapable of reproduction, but they get three pages (278 through 280). They presumably deserve more attention and admiration because they show two major features (jaws and true bone) that also occur in the AMEH.

They are not, however, so admirable that Silver, Burdett's writers have actually tried to learn about them. Page 280 says that a bony fish has an air bladder: "The air bladder contains gas and helps the fish stay at a certain depth in the water [?] without using much energy [?]. As the fish changes depths, the amount of gas in the air bladder changes." The writers now pose a question to the student: "As a fish swims from a greater to a lesser depth, would the amount of gas in the air bladder increase or decrease?" The question is absurd and unanswerable: The writers do not know the relevant ichthyology or physics.

Higher up on the imaginary ladder we find the amphibians. These can reproduce! And they receive four pages, a generous award that must reflect the fact that many amphibians have lungs and limbs, just as the AMEH does. We are now getting to the really proper animals. Even so, Silver, Burdett's text about amphibians is inadequate, misleading and often silly.

Up another rung, to what Silver, Burdett's writers call "reptiles." These are said to comprise the dinosaurs, the turtles, the crocodilians, the snakes and the lizards. The writers fail to tell that the dinosaurs include (as an important subgroup) the birds. This failure is hardly surprising. In the liturgy of the ladder, birds are deemed to be especially admirable and man-like, chiefly because they are endothermic; so they must be decisively separated from "reptiles," which are deemed to be lowly.

The reptiles get slightly more space than the amphibians got, and the text acknowledges that reptiles can reproduce. The writers evidently do not know much about this, however, for they believe that all reptiles lay eggs. That is quite false, but it presumably helps to sustain belief in nature's ladder. (The idea that the vertebrates represent a linear progression -- a progression in which organisms become increasingly man-like -- collapses if we notice that some humble, ectothermic reptiles give birth to live young while all those glorious, endothermic birds lay eggs. In fact, it collapses as soon as we notice that some fishes give birth to live young.)

Now climb higher. The birds get seven pages, including a long passage about migration -- a topic that the writers have entirely ignored in their "information" about the ectotherms. And there is a full page, with a cross-sectional diagram, about bird eggs. Needless to say, no such attention has been granted to fish eggs, amphibian eggs or reptile eggs.

Climb higher. And here they are: the mammals -- sitting only one rung from the top of the ladder and commanding nine pages! The top rung, of course, is reserved for man, who gets pages by the score.

If you think that Silver, Burdett's devotion to an old superstition is funny, or that making a "science" book fit this superstition is harmless, think again. Think of how perpetuation of the ladder requires gross misrepresentations and the wholesale suppression of information about the diversity of life on Earth. Think of what it does to the student who is particularly interested in some group of organisms that the ladder-peddlers dismiss as unworthy of any serious notice. And please think back to the Reagan Administration, when some primitives proposed amending the Endangered Species Act to give greatest protection to birds and mammals, less to "lower" vertebrates, and least (if any) to things that had no bones. The proposal failed after it was disgraced by scientists and environmentalists, who pointed out that it had no basis in science or in any imaginable principle of environmental management. It was based on nothing but the same pretension that Silver, Burdett is dispensing -- that organisms are innately more important, less important or worthless, according to how man-like they are.

As I've said, that particular proposal failed. The potential for such idiotic mischief remains, however, and the potential can only increase if schools disseminate the bogus "science" represented by Silver Burdett & Ginn Life Science.

Michael T. Ghiselin is a biologist, a historian of science, and a senior research fellow at the California Academy of Sciences. His interests include systematics, reproductive biology and comparative anatomy. His books include The Triumph of the Darwinian Method and The Economy of Nature and the Evolution of Sex.

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. He writes often about the propagation of quackery, false "science" and false "history" in schoolbooks.

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