Book Reviews

Michael Emsley Department Editor

materialpresented in the essays. A few essays were more | HUMANGENOME PROJECT | personal accounts, such as those of Nobel laureatesWalter Gilbert and James D. Watson, and did not include such The Code of Codes: Scientific and Social Issues in the references. These references will be of great value to the Human Genome Project. Edited by Daniel J. Kevles reader. The book also includes a 10-page selected bibliog- & Leroy Hood, 1992. HarvardUniversity Press. (79 Garden raphy, a glossary of terms helpful for the lay reader, and a St., Cambridge,MA. 02138). 397 pp. Hardcover$29.95. brief curriculumvitae of each of the contributors. The Code of Codes is an interesting book that clearly Z2gyJ~ The Code of Codes, is an exciting collection of essays >ZBgy exploring the human genome project and its possi- presents the science and technology of the human genome Downloaded from http://online.ucpress.edu/abt/article-pdf/55/7/446/46208/4449708.pdf by guest on 29 September 2021 ble social consequences. The essays present the project. The many different voices of these essays raise history of the project, the development of the essential stimulating questions about the social impact of these science and technologies, the medical applications,and the advances. This book will be an importantresource for the ethical and legal implications. high school and college biology teacher for the science and The book is an expansion of a series of seven lectures the social aspects of the human genome project. presented at The California Institute of Technology in Susan J. Karcher 1989-1990. The 14 chapters of the book are written by an PurdueUniversity impressive group of 13 experts in science, history of sci- WestLafayette, IN 47907-1392 ence, and law. The book is divided into three parts: the history, the science and the social aspects of the project, although there is much overlap. Daniel Kevles begins TheCode of Codeswith a chapterthat presents the early history of genetics, including the infa- mous eugenics of the 1920s and 1930s. The chapter then gives the history of the beginnings of the human genome | EVOLUTION project with Sinsheimer and DeLisi's founding efforts. Kevles includes an overview of concerns about the project Living Fossil: The Story of the Coelacanth. By Keith and covers work on the human genome project in Europe StewartThomson. 1991.W. W. Norton & Co. Inc. (500Fifth and Japan. The second chapter, written by history of Ave., New York, NY 10110). 252 pp. Hardcover$19.95. science professor Horace F. Judson, gives the scientific v Keith Stewart Thomson, president of the Academy background for all the relevant techniques and methods. Bi0,Igr of Natural Sciences, is a born storyteller, a paleon- The second section of the book includes a fascinatingchap- --- tologist with a fondness for collecting clues and ter on DNA-based medicine by C. Thomas Caskey and a then sorting out the bits and pieces of evidence into a chapterby Leroy Hood that describes advances in automa- sense-making narrative.In the LivingFossil, he has pulled tion that will make the project progress more rapidly. together a marvelous tale of biologicalsignificance and has The third section of TheCode of Codesfocuses on the social imbued the scientific text with the enriching flavors of implications of this genetic information. Issues such as narrative that includes mystery, intrigue and adventure problems of the "pre-symptomaticill," health insurance spiced with sketches of human personalities that influence coverage, and implications of prenatal diagnosis are dis- research. cussed. This last section includes an interesting chapteron Years back, when news headlines communicated the DNA fingerprinting by Eric Lander and a chapter about "important"events of the world, I was impressed by the Huntington's disease by Nancy Wexler.The social issues of "sensational"announcements relating to fossil fish discov- law are presented by Henry T. Greely. eries by a group of fishermen. I was delighted to learn The book ends with detailed notes, listed by page num- through the popular medium that dogmatic preconcep- ber, that provide an excellent list of references for the tions, even when embedded in encyclopedic text, need not be correct.The news shatteredmy conception of science as a body of fixed knowledge and delighted me with the view Michael Emsleyis editor of the BookReviews section of ABT.He that there is always something new under the sun. is professorof biology at George Mason Universilyand sits on Coelocanths were considered fish indigenous to Meso- the editorialboard of the George Mason UniversityPress. Emsley, zoic times and were known from fossil remains from 60 who holds a B.S.and Ph.D.in zoology from the Universityof million years ago, thus they were long believed to be London,is an insect taxonomistcurrently working on a projectto extinct. Thereforeit was startling for MarjorieCourtenay- identifyand classifya genus of katydidsfound only in Central Latimer, a museum curator, to note this incongruous big and SouthAmerica. The project,begun in 1958, includesexam- iningthe sound producing mechanism of the insects. Emsleyis blue fish amongst a mess of sea trawl dumped on a pier in the author of Bufferfly Magic, Insect Magic and Cloudforests Cape Province, South Africa. Professor J.L.B. Smith, a and Rainforests.His address is: Biology Department, George dedicated ichthyologist, confirmedthe novel specimen as a Mason University,Fairfax, VA 22030. coelacanth and named it Latimeriachalumnae, in honor of the discoverer and for the river in which it was found. In

446 THEAMERICAN BIOLOGY TEACHER, VOLUME 55, NO. 7, OCTOBER1993 this book, Dr. Thomson engagingly describes the tale caused by a large meteor crashing into the Earth 65 million behind finding the living Coelocanths and relatives while years ago at the end of the Cretaceous Period. he unwinds their biological mysteries and ponders their Findings of the last few years have added weight to the endangered status. argument that, indeed, the dinosaurs did die because of an After this first find in 1939, other specimens were anx- impact that caused the Chixulub crater in the Yucatan iously sought. Fishermen along Africa and Madagascar Peninsula of Mexico. This enormous crater, 180 km in were conscripted into the hunt. Wanted posters, with huge diameter, has been dated at 65 million years which is the rewards, featuring illustrations of the five-foot, approxi- time of the Cretaceous extinction. mately 100-pound bony fish with the unusual fins were Raup's book discusses, in a compelling way, that extra- sent out to all fish stations along the mainland and through- terrestrial objects (meteors, comets etc.) hit the Earth with out the islands. With this publicity, subsequent catches great regularity, and may be the cause of most, if not all of, were made along the Comoro Islands located between the the mass extinctions which are scattered throughout the northern tip of Madagascar and the African Mainland. fossil record. Specimens were sought by museums in major world cities, Raup also discusses some of the statistical methods he and national politics finally played its role in determining uses to come to his conclusions. These explanations are the site for study. Recently, a diver in the coral waters off excellent and could easily inspire a student to go into such the Comoro Islands observed and recorded groups of a field of study. For example, we are used to thinking of active, living and undisturbed coelocanths. events fitting a bell-shaped curve. This idea would predict

Due to the hollow spines found in the first dorsal fin, that most meteors which hit the Earth are medium sized, Downloaded from http://online.ucpress.edu/abt/article-pdf/55/7/446/46208/4449708.pdf by guest on 29 September 2021 Louis Agassiz first named this group coelacanths by com- with a few very small ones and a few very large ones. This bining the Greek coel = space with acanthus = spine. distribution, in fact, is not what happens. It is much more Never quite as appealing as dinosaurs to the general public, likely that a small meteor will hit the Earth because there biologists regard Latimeriawith special reverence. Because are so many more small meteors than large ones, and the coelacanths fall within the superorder of Crossopeter- conversely, fewer large meteors. Therefore, if you plot the ygii-the lobe-finned fish-they are a close relative to size of the meteor vs. the frequency of its hitting the Earth, ancestral forms of land-dwelling vertebrates. Their limblike you come up with a curve that shows many small, some fins hint of a special relationship to tetrapods, and they medium-sized and very few large meteors. have been described as a missing link between fish and Raup then discusses some of the smaller meteors which man. have hit the Earth. For example, in 1908 in Tunguska, an This narrative tells the extraordinary story regarding the uninhabited region of Siberia, a meteor exploded in the find of a living form thought to have been extinct for atmosphere and leveled trees for thousands of square millions of years and of the efforts to learn the biology and miles. The explosion was heard by passengers on the behavior of this species, its connections along the evolu- trans-Siberian railway several hundreds of miles away. tionary trail, and human pursuits to get the specimens first Fortunately, nobody was killed because the region was hand. The danger now exists that man's curiosity may uninhabited. He also points to the many craters around the cause the fossil fish to truly become extinct. The sense of world that were formed by larger meteors which have discovery and reassessment of understanding flows crashed into the Earth. through this tale. The reader pursues the events and Raup then goes on to say that if a meteor this large has hit discoveries that delight the author as he knits the story the Earth in the last hundred years, what are the chances together even though, "Science can be maddening because that every few hundred million years, an enormous meteor one never gets information in the right order." will hit the Earth and totally disrupt the life then on the planet. Raup describes the five largest mass extinctions which Rita Hoots have occurred in the last 500 million years, and shows that YubaCollege these are just the large end of a continuum of mass Woodland,CA 95776 extinctions which have occurred during this time. He further shows that the magnitudes of these extinctions follow curves which can be made of the frequency of asteroids of different sizes colliding with the Earth. The inevitable conclusion is very powerful; that most of the time Darwinian evolution prevails, but every few tens or hun- EXTINCTION dreds of million years, a large meteor collides with the Earth causing chaotic conditions on Earth. These meteor collisions result in large-scale extinctions of species that had Extinction: Bad Genes or Bad Luck. By David M. Raup. been well-adapted to live under "normal" circumstances. 1991. W. W. Norton & Co., (500 Fifth Ave., New York, NY After the meteor collision, conditions on Earth gradually 10110). 210 pp. Hard cover $19.95. become normal again, and new species evolve in an adap-

Bi.ogyIt is always a treat when a popular book is written tive radiation. I suspect that few of us teach that major m7Jby a scientist who is a leader in the field. It is even discontinuities are a regular and important part of the more of a treat when the book gets you to think history of life. Raup maintains that these discontinuities are about science in a new way, while at the same time inviting indirectly responsible for the complexities of contemporary you to explore the methods used in the field. Extinction:Bad life. He points out that organisms that have survived all the Genes or Bad Luck? is just such a book. catastrophes, such as bacteria, are very simple. He believes David Raup is one of the paleontologists who, in the that it is unlikely that complex organisms such as mammals early 1980s, called attention to the existence of numerous could have evolved from simple beginnings in the shadow mass extinctions throughout the history of the Earth. This of the large successful reptiles of the Mesozoic. So it was revelation was at a time when everybody was excited about the demise of the dinosaurs which made it possible for new the theory that the extinction of the dinosaurs had been species of mammals to evolve. Similarly, an earlier mass

BOOKREVIEWS 447