Earth as seen from the Apollo 17 mission. Evolution encompasses both the universe and our world. Source: Johnson Space Center of NASA.
Note: Because some of the information in this article may be outdated, it has been archived.
Editor’s Note: This article refers to a 2000 study of state science standards. State science standards have been reexamined since then and a new study was published in 2005. To read the 2005 study, refer to the link “Fordham Reports” in the “learn more links” that follow this article.
Evolution, the sequence of events by which the world came to be as we see it today, is the central organizing principle of the historical sciences — biology, geology, and cosmology. Ongoing collection of evidence concerning the details of the process, and elaboration of the theoretical structure that makes the evidence comprehensible, lie at the hub of these sciences. Scientists spend much time debating the details, but there is a consensus as to the overall picture and the basic principles.
As in all the sciences, the role of public education is to inform students to a degree that makes it possible for them to understand, at least in general outline, what science and scientists are about. But this is not what happens in some parts of the United States. Some persons, generally called creationists, perceive the scientific consensus as inimical to their religious beliefs. Creationists have had some degree of success, through political means, in suppressing or distorting the teaching of science in localities of various sizes, ranging from individual classrooms through schools and school districts to entire states.
The biological sciences are the arena in which this effort at suppression and distortion has been most visible and by far most extensive. The effects are evident in the kindergarten through high-school (K-12) science standards of a number of states.
- In some states, biological evolution is simply ignored, reducing the study of biology in schools from a science to a sort of natural history.
- In other states, evolution is soft-pedaled, removed from its proper place at the center of biology, represented as a field of hot scientific controversy, or presented in veiled terms.
- In one state — Kansas — all references to the historical aspects of all the sciences have been expunged from the standards.
Assessing science standards in education
The U.S. educational system is highly decentralized, with primary authority resting at the local school-board level. Nevertheless, states exercise a significant degree of control over every aspect of education through teacher certification, class-size rules, significant subsidies, and other regulations. With respect to specifically curricular matters, two major instruments of statewide quality control are
- K-12 standards
- the statewide examinations that are based on them
I had studied the overall quality of state science standards in two earlier publications. State Science Standards: An Appraisal of Science Standards in 36 States was published in 1998. An update, The State of State Standards 2000, covered the 49 states that had published standards by the end of 1999. Both of these reports were published by The Thomas B. Fordham Foundation. In these general studies, it became apparent that the treatment of evolution, particularly biological evolution, varied widely from state to state and that this variation had a substantial effect on the overall quality of the science standards. It was therefore decided to study the treatment of evolution in a more specific way.
I have used the K-12 science standards of 49 states1 and the District of Columbia as a measure of the quality of instruction in evolution. Because it is the subject that evokes the most public controversy, I concentrated on biological evolution. However, the tight connections between the evolution of life and the evolution of the nonliving earth, and between the latter and the evolution of the solar system and the universe, obliged me to pay some attention to those subjects as well. The results of the study of the treatment of evolution in the science standards have been published as Good Science, Bad Science: Teaching Evolution in the States (September 2000). Like the earlier works, this report was supported and published by the Fordham Foundation.
Instruction in evolution
Given the central place of evolution in the life sciences, what then is required to provide the student with a good understanding of these sciences and the unifying role that evolution plays in them? As with all the sciences, the theoretical framework of biological evolution is somewhat abstract. It does not reveal its power to persons who are not familiar with a reasonable sampling of the broad spectrum of facts that the theory explains and correlates. At the primary grade levels, therefore, standards should focus on those basic facts and ideas of evolution that can later be incorporated into broader perspectives. At the K-3 level, for instance, students should be expected to understand that:
- all living things reproduce
- offspring are similar to but not exactly like their parents
- offspring have to grow up (or change; i.e., metamorphose) before reproducing themselves
- there is a fit between individuals, or species, and their environment (e.g., terrestrial, aquatic, aerial)
- the earth is over 4 billion years old, allowing much time for biological as well as geological evolution
At higher grade levels, these ideas can be supplemented by an understanding of:
the nature of competition for survival between and within species
the consequence that not all offspring live long enough to reproduce
the limitation imposed on the number of offspring that survive by such environmental factors as availability of food and water, predators, and temperature
the variability among individuals that leads to differential survivability in a particular environment
the specialization of species to fit ecological niches and the impact of environmental change on the tenability of those niches
the underlying role of genetic variation that results from both sexual reproduction and random mutation
the nonrandom way that natural selection operates on the existing population in spite of the many random factors that determine the survival of any individual
At the middle and high school levels, these ideas can be unified, and such concepts as Mendel’s laws, genetic drift, sexual selection, and other significant mechanisms can be introduced. Coevolution, commensalism, and the complex interactions of ecosystems are important applications of the basic concepts. The magnitude of the geological/evolutionary time scale is so different from the time scales of everyday life that it is difficult to grasp, and must be introduced with care. The fact that the same general time scale underlies both geological and biological evolution is an important link between the two sciences.
Parallel to these macroscopic concepts, the underlying microscopic mechanisms must be introduced at suitable high school grade levels. These include:
- the relation of genotype to phenotype
DNA as an information carrier
the expression of DNA in protein synthesis
the implications thereof at the various levels of organization from organelles through cells, tissues, organs, and individual organisms, to populations
the identification of Mendel’s and Morgan’s abstract gene as a sequence of bases in a DNA molecule, a dramatic triumph of the biological sciences
the origin of mitochondria and chloroplasts in prokaryotes parasitic on eukaryotes
the special roles of mitochondrial and Y-chromosome DNA in tracing single-sex ancestral lines
It is also important to introduce, at the proper time, the understanding that biological evolution does not take place in a vacuum.
- The biota of the earth coexist with the nonliving parts of the earth, and each influences the other.2 Therefore, the facts and, subsequently, the theoretical structure of geological evolution must be introduced concurrently with biological evolution.
- Similarly, the earth is part of the solar system and the solar system is part of a hierarchy of still larger structures, up to the universe as a whole. The student should be empowered to view the history of the universe, from the general cosmological picture down to the smaller scales characterizing the earth and its smaller elements, as a seamless whole.
Misconceptions about evolution
Why do creationists object to these ideas? The extrascientific pressures against the teaching of biological evolution are diverse. However, they manifest themselves mainly in three major classes of objections, which correspond to the following factual and theoretical implications of biological evolution:
- To achieve the diversity of life we observe today, the evolutionary process has required several billion years.
- All living things, humans not excepted, are descended from common ancestors.
- The evolutionary process is a natural one susceptible to scientific investigation and thus by definition cannot include supernatural intervention as a necessary component.
The first of these premises conflicts with a particular interpretation of the first few chapters of the Book of Genesis. According to this interpretation, the universe is less than a millionth as old as the scientific evidence implies — that is, a few thousand years rather than some tens of billions. This particular interpretation of Genesis, generally called young-earth creationism, is held mainly by a subset of evangelical Protestants and some ultra-orthodox Jews and Muslims. Young-earth creationists fear that the several alternative interpretations of Genesis supported by most Christians and Jews undermine the entire authority of the Bible.
The second premise is objected to by young-earthers and some others who hold that humankind has a special, divinely ordained place in the universe and is the central concern of the divinity. According to this belief, God could not have lumped humans (for whose benefit He created the universe and everything in it) with mere animals, let alone other living things. Such believers hold, moreover, that teaching the biological relationship of humans to other animals inevitably undermines any possible moral or ethical teaching.
The third premise, though shared by the groups discussed above, is the special province of a class of anti-evolutionists called intelligent-design3 or irreducible-complexity advocates. These persons have revived a position set forth in the 17th century by John Ray4 and just after 1800 by William Paley.5 Specifically, they dust off the view that living beings are too complicated to have evolved, and that their creation by an intelligent (read as divine) designer is just the entr¨Ĥe into the natural world that God requires if we are to believe in Him.
Other pressure groups object to evolution as well, on various grounds and from political perspectives that range from right to left or are not classifiable politically. However, the views described above, held mainly by a subset of Protestant evangelicals, have by far the greatest impact on public education in the United States.
How states respond to critics of evolution
States that respond to creationist pressure do so in different ways and to varying degrees. The responses ordinarily take one or more of the following forms:
- The standards include many of the central principles of evolution, usually briefly, but the word evolution is carefully avoided. The “E-word” is replaced by misleading euphemisms such as “change over time.”
Biological evolution is simply ignored. Geological evolution, the history of the solar system, and cosmology may well be treated, often even employing the word evolution. Fossils are sometimes mentioned, but only in the context of geology, not biology.
Evolution of plants and animals is treated to some degree but human evolution is ignored.
All scientific discussions that imply an old earth or universe are deleted. Kansas is the only state to do this completely, but Mississippi, Tennessee, and West Virginia come close.
Creationist jargon is used.
In Alabama, all textbooks are required to carry a disclaimer that calls evolution “controversial” and labels it “a theory, not a fact.” The disclaimer also cites a number of other standard creationist ploys, all of them based on fallacious understanding of science.
Some or all of the historical sciences are treated lightly but no attempt is made to elucidate the connections among them.
How the states rate in teaching evolution
A scale was developed to rate state science standards. It gave positive credit for the fulfillment of the principles of evolution enumerated above and negative credit for the incursion of creationist notions. The numerical scores were reduced to letter grades A through F; Kansas was unique in earning a negative score and was rated F-minus. The table below gives the distribution of grades:
|# of States||10||14||7||6||12||1|
|States||CA, CT, IN, NJ, NC, RI, SC, DE, HI, PA||CO, MN, VT, WA, MI, AZ, ID, MA, MO, MT, OR, SD, UT, DC||MD, NM, NV, NY, NE, LA, TX||AR, KY, WI, VA, AK, IL||WY, ME, OH, OK, NH, FL, AL, ND, GA, MS, TN, WV||KS|
It is gratifying that 31 — almost two-thirds — of the states do a satisfactory to excellent job of teaching evolution. But that is cold comfort in view of the other 19 that do a poor to awful job. Among those failing states, moreover, are several with quite large student populations, notably Florida, Illinois, Ohio, Wisconsin, and Virginia.
Although there is a concentration of poorly performing states in the Bible Belt, it would be wrong to generalize. Note, for example, that North and South Carolina have excellent standards, and Louisiana and Texas squeak by. On the other hand, Maine, New Hampshire, Illinois, and Wyoming have unsatisfactory standards or worse.
Changing the situation
The American public education system is based on the concept of local control with limited oversight from the state. One may characterize American public school governance as a modified diffuse democracy.
In democracies, decisions are made by majority rule. Citizens vote with equal voice on the basis of their opinions, regardless of what those opinions are or how strongly founded in fact they may be. We believe, of course, that a well-educated electorate is an essential basis for workable democracy, and this has always been a cardinal argument for public education. But democracy cannot permeate all aspects of every social institution. It is certainly not consistent with the education process itself. Education cannot be democratic because the teacher directly supervises the progress of the students, using his or her superior knowledge and adhering to standards imposed from levels above the classroom.
Science is not democratic, either. In a democratic society, citizens who do not like the existing state of affairs can change it. This has happened often. (Consider, for example, the Sherman Antitrust Act, the Prohibition Amendment, and the repeal of that amendment.) But nature is not so flexible. We may find Newton’s second law of motion contrary to common sense because it links acceleration, rather than velocity, to applied force. But we cannot change this; what we can do is learn how to manipulate it. We may believe it an insult to human dignity that the earth is not at the center of the universe but we cannot move it there. We may find moral or aesthetic objections to the manner in which natural history unfolds but we cannot command nature to take another course.
Science is also undemocratic in the social sense, i.e., those who do not have the scientist’s special knowledge, skills, and experience cannot have equal voice in achieving a scientific consensus concerning a class of phenomena. The public school has no authority to impose opinions on its students. But it has the duty to explain to them the consensus of scientists on any particular issue, and the methodology by which scientists proceed to discover new knowledge and merge it into that consensus.
Biological evolution is just one of the most important of many broad issues on which substantially all working scientists agree. There may be a few persons with scientific credentials who disagree, but they do not contribute to the progress that is the hallmark of science. It is not simply that these dissenters are wrong, because wrong answers can sometimes stimulate controversy that helps lead to correct answers. Rather, as the physicist Wolfgang Pauli liked to say, they are not even wrong. That is, their arguments are useless and even detrimental to the pursuit of further knowledge.5
This being the case:
The publication and maintenance of scientifically accurate curriculum standards is a vital quality-control function of the states.
Given the far-reaching ramifications of evolution in the life sciences — to say nothing of the other historical sciences — a complete and proper exposition of evolution is an essential constituent of state science standards.
- Shortchanging, distorting, or omitting evolution indeed harms the teaching of the life sciences. Further, it makes it difficult for the student to come to a clear understanding of how science works. No one disputes, of course, the importance of teaching scientific literacy to the coming generation of citizens.
Given this state of affairs, a school district, or a state, cannot argue that it is a simple matter of democracy to advocate a scientifically unacceptable opinion because a majority or vocal minority of citizens holds that opinion. One can understand the desire of parents to raise their children to think as they do. But if the parents’ belief is based on poor understanding of the content and methods of science, it is well if they hope and expect that their children will understand science better than they do. In doing so, parents will provide the means to expose the children to expertise beyond their own. Indeed, that is why most parents want to send their children to school.
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