Mummies, Dinosaurs, Moon Rocks: How We Know How Old Things Are

Explains how archaeologists and other researchers determine the ages of ancient things in an exciting, fact-filled science book discussing the various tests that can be performed and the meanings behind significant markings and natural clues, such as tree rings.

Grade 6-9?Carbon dating, thermo luminescence, and counting tree rings are just some of the methods used to determine the age of various objects. This book follows scientists as they examine old things including mummies, the Dead Sea Scrolls, violins, and even stars, and then use everything from hunches to highly scientific techniques to place these items on a time line. This book should be noted for its original research; Jesperson and Fitz-Randolph have taken the time to get the facts "straight from the scientists' mouths." It's also more up-to-date than many books, and includes information on recent finds such as the mummified Iceman and human artifacts in Brazil that predate previous evidence of human life in the Americas. On the downside, this book's drab presentation and its bland illustrations are so lackluster that one can expect it to collect dust on the shelf without a hard sell by librarians or the dire need inspired by a homework deadline. Many of the techniques used to date objects are difficult to understand, providing a perfect opportunity for illustrations to make the text more comprehensible. Instead, readers will enjoy the tales of discovery, but may find themselves bogged down with technical descriptions, without much help from the pictures to explain them.?Cathryn A. Camper, Minneapolis Public Library
Copyright 1996 Reed Business Information, Inc.

Subtitling their work ``How We Know How Old Things Are,'' the authors write with enthusiasm and include up-to-date information about ``many ways of finding the age of objects ranging from the relatively young--like pottery and old musical instruments--to fossils and the earth itself.'' Each method is put in the context of current and evolving scientific puzzles that will appeal to young readers: Methods include Carbon 14 dating, thermoluminescence, potassium-argon dating, dendrochronology, analysis of DNA, etc. Examples are wide ranging and intriguing, e.g., where did Columbus land that Christmas of 1492 and establish La Navidad? Scientists analyzed the strontium atoms in a pig's tooth found on one site and determined that it probably came from Spain close to the port from which Columbus sailed. In other stories, the scientists separate human blood from pigment in cave paintings to learn more about the artists or employ a process known as a polymerase chain reaction to look for genes in Neanderthal blood. Like a good detective story, the book will hook even casual readers, who will be subsequently enthralled. (b&w photos, diagrams, glossary, further reading, index) (Nonfiction. 10+) -- Copyright ©1996, Kirkus Associates, LP. All rights reserved.

Gr. 6^-8. It's not easy to present sophisticated scientific principles in a manner that will be accessible to students with limited knowledge of biochemistry and physics, but Jespersen and Fitz-Randolph have done an admirable job. In addition to providing detailed descriptions of methods used to determine the ages of natural and man-made materials, explaining the principles behind them, and providing a brief history of investigations in dating, they cite examples guaranteed to interest middle-graders (everything from garbage to speculation about mass extinctions). Readers may already know about carbon dating and tree-ring study, or dendrochronology (both thoroughly described here), but they'll also learn about potassium-argon and thermoluminescence dating. Simple drawings and black-and-white photographs provide additional information. A glossary and annotated bibliography are appended. Chris Sherman