Evolution



Evolution in the biology curriculum. Some students question why evolution is such an important part of the biology curriculum. Here is a statement from BSCS (Biological Sciences Curriculum Study) on the matter. It was published in their March, 1997 newsletter and is reproduced here with permission.

THE TEACHING OF EVOLUTION: BSCS RESPONDS TO A STUDENT'S QUESTIONS

During any given year, BSCS receives thousands of inquiries about its programs, and a fair amount of feedback about its content and instructional strategies. Although we receive our share of compliments, people also write to complain, and they complain most frequently--still--about the treatment of evolution in our programs.

Since the original BSCS textbooks (Blue, Green, and Yellow Versions) put evolution back into the curriculum in the early 1960s, BSCS has been in the middle of an ongoing controversy that has nationwide implications for the content of the curriculum, the control of public education, and even interpretations of the Establishment Clause of the First Amendment to the U.S. Constitution. We have been embroiled in battles that have ranged from local schools and state textbook adoptions, to the national media and the federal courts. Sometimes we have lost, but we have never backed down; we have done our best to protect the integrity of science teaching and to represent evolution as the central organizing theme of biology.

We spend a fair amount of time dealing with creationist complaints and challenges to our programs. Many of those challenges are well-organized, spearheaded by local, regional, or national groups that oppose the teaching of evolution, often as one part of a larger social and political agenda. Among the most interesting critiques we receive, however, are those from students. Such critiques often reiterate misinformation that students have acquired from adults, either formally or informally. Our responses provide opportunities to correct the misconceptions that these young people hold about evolution and about the nature of science. The letter on page 2, written by a high school student who is using the BSCS Green Version, is illustrative. My response follows.

It is difficult to quantify the amounts of time and money we spend responding to attacks on the teaching of evolution, but they are not trivial. Neither, however, are the principles at stake, especially where students are concerned. Joseph D. McInerney Director, BSCS 


To whom it may concern:

I am a high school student and am currently enrolled in a biology class. In this class, we are using your books entitled Biological Science: An Ecological Approach. In chapter 9 ("Continuity Through Evolution"), you presented your ideas about the theory of evolution as fact instead of theory, or in some of the cases, idea. This is prohibited by law, especially if the teacher presents it as a fact. Most of my classmates feel the same way I do. I encourage you to do further research of this subject, especially since Charles Darwin died a Christian. It is not the only process that explains where all living creatures come from, as stated in the book. In closing, please reword this chapter so as not to make any student or teacher actually think that a theory based on teeth and bone fragments (much less head size) is a fact. I thank you for your time.
 

Dear Student:

Thank you for your letter about the treatment of evolution in the our program Biological Science: An Ecological Approach. I appreciate your taking the time to write, because your letter provides an opportunity to explain our treatment of evolution and to clarify some central misconceptions you hold about this extremely important topic.

1.   You are concerned that our "ideas about the theory of
     evolution are [presented] as fact instead of theory, or in
     some cases, idea." Two points are critical here. 

          First, the fact of evolution--the fact that species have
          changed during the immensely long history of life on
          earth--is not in dispute among scientists. This fact was
          obvious to many scientists before the time of Darwin, and
          its validity is clear to anyone who examines the fossil
          record. There is some disagreement within the scientific
          community about the exact mechanisms by which evolution
          occurs. For example, there is some dispute about the
          nature of adaptation and about the pace of evolutionary
          change. Such internal disputes, however, are
          characteristic of science, irrespective of the
          discipline, and they do nothing to challenge the validity
          of evolutionary change as an established fact.

          Second, your sharp contrast between "theory" and "fact"
          leads me to suspect that you do not yet understand the
          concept of theory in science. The public often confuses
          the term "theory" with the notion of a guess, akin, for
          example, to my "theory" about why the Denver Broncos will
          not win the Super Bowl next year (they need a better
          offensive line). In contrast to its connotations among
          the general public, a theory in science is not a guess.
          It is, rather, an extremely sound conceptual framework
          that explains numerous observations and experimental
          results and that generates fruitful scientific
          hypotheses. Science has a number of great theories:
          gravitation, the germ theory of disease, atomic theory,
          plate tectonics, electromagnetism, the chromosome theory
          of inheritance, cell theory, and evolution. All of these
          theories are supported by a huge amount of data collected
          and verified by the methods of science. The fact that
          scientists refer to these compelling conceptual
          frameworks as "theories" does not detract from their
          validity or their explanatory power; the problem is with
          the public's confusion about what the term means.

2.   You have said that the presentation of evolution as fact
     rather than as theory "is prohibited by law." This emphatically
     is not the case. Indeed, as the enclosed material on the legal
     history of the evolution/creation controversy indicates,
     exactly the opposite is true. One cannot legally prevent the
     teaching of evolution (as fact or theory). It is, however,
     illegal to mandate the teaching of creationism, a doctrine
     that is rooted in religious beliefs and whose promotion in a
     public school, therefore, represents a violation of the
     Establishment Clause of the First Amendment to the United
     States Constitution, which guarantees separation of church and
     state (see the enclosed copy of the First Amendment).

     As the enclosures indicate, several states or counties have
     enacted or proposed regulations and legislation designed to
     weaken the treatment of evolution and to promote religious
     perspectives about life on earth. These attempts are foolish,
     generally erroneous, and almost certainly unconstitutional.

3.   You have encouraged BSCS "to do further research on this
     subject, especially since Charles Darwin died a Christian."
     Again, two points are important here.

          First, BSCS materials are developed and reviewed by well-trained, 
          knowledgeable biologists. Our programs often are
          cited as among the best in the United States because of
          their accuracy and currency. The treatment of 
          evolution--and Darwin--in our programs is consistent with the most
          widely accepted, up-to-date thinking in the biological
          community, interpreted at a level appropriate for high
          school students. You might find some minor errors of
          fact, but you will find no major faults in the conceptual
          basis of the biology presented in the program you are
          using.

          Second, whether Charles Darwin "died a Christian" is
          irrelevant to the validity of the insights he produced,
          to our presentation of those insights, or to the
          confirmation of his views by sound research since the
          publication of On the Origin of Species by Means of
          Natural Selection, in 1859. Science does not, indeed
          cannot, address issues related to religion. Religion is
          a system rooted in revealed, unquestioned knowledge and
          faith; it is based in the supernatural. Science assumes
          that the universe is explainable without appeals to
          supernatural events; it depends on knowledge constructed
          by rational analysis and it is driven by data.
          Irrespective of his or her religion, a scientist must go
          where the data indicate, even if the destination calls
          into question long-standing, comfortable myths such as
          the Genesis story of creation. 

          Your statement that "[evolution] is not the only process
          that explains where all living creatures come from" is
          germane here. You are quite correct; evolution is not the
          only process to explain that phenomenon. It is, however,
          the only scientific process that makes sense and that
          meets the requirements of a scientific explanation.
          Others can propose or accept other, nonscientific
          explanations; that is their right. Our objective,
          however, indeed our obligation, is to present sound
          science. Creationism has absolutely no basis in science
          and we do not, therefore, treat it as a scientific
          explanation for the origin or diversity of life on earth.

4.   You question whether "a theory based on teeth and bone
     fragments (much less head size)" can serve as an adequate
     explanation for life on earth. Whether you choose to accept it
     or not, the evidence for the relatedness of all species by
     descent with modification is overwhelming. Some of this
     evidence is derived, as you indicate, from the fossil record.
     Some is derived from fields such as comparative anatomy and
     developmental biology, which compare structures, functions,
     and developmental programs among living representatives of
     closely related species. Additional evidence comes from cell
     biology, biochemistry, genetics, and molecular biology.
     Virtually all life on earth, for example, shares the same
     central information molecule--DNA. The sequence of DNA bases
     in humans and chimpanzees--our closest living relative--is
     about 99 percent identical. 

     In short, in the words of paleontologist Niles Eldredge, "all
     life shares a single, complex history." That history is
     written in the genes in every cell in your body, and it tells
     the story of biodiversity produced by descent with
     modification, with natural selection as the prime mover over
     enormous expanses of time. You may choose to embrace other
     explanations, but again, I caution you to be aware of those
     that meet the requirements of science and those that do not.
I have provided a number of enclosures that may help you understand some of the perspectives I have outlined above. I also have sent a copy of this letter and its enclosures to the biology department at your school so that the biology teachers there can read my response to your concerns. This may help them address questions from your classmates, who, you state, share your concerns.

I thank you again for writing, and I commend you for challenging material with which you disagree. I trust the foregoing information and the enclosed materials will help you understand my views and those of BSCS. Please do not hesitate to contact me should you have additional questions. I travel to your area on occasion and would be happy to visit your school to explain my views in more detail. Alternatively, you might wish to contact one of the many fine biologists at your local university for more information about evolution. Best regards.

Sincerely,

Joseph D. McInerney Director