Like the same authors' Subnuclear Zoo (1978), this moves one to question the widespread assumption that any subject can profitably be treated at any level. Engdahl and Roberson apprise children of some of the current and possible uses of our knowledge about genetics--from crossbreeding of horses and artificial insemination of cows to direct tampering with bacterial genes in order to produce strains that will make insulin or clean up oil spills--and they let it be known that there axe ""differences of opinion"" on the desirability of genetic engineering. ""Some people"" associate the word eugenics with the Nazis' evil actions. . . or fear that eugenic practices will reduce the healthy variety of the human gene pool. . . or worry that unpredictable diseases might result from gene splicing. ""Other people"" point out that any kind of knowledge can be abused; they applaud the progress made in helping couples through genetic counseling, and they believe that the potential benefits of genetic therapy and gene splicing make the risks worthwhile. The authors don't take sides overtly and they repeatedly emphasize that the dangers are real, but their chapter headings are glowingly positive and they tip the balance of ""some"" and ""other"" people with the assertion that ""the majority of people do not consider it necessary to completely stop recombinant DNA research."" One wonders, though, how much any of this will mean to children who have at best a fuzzy notion of what a gene is and how bacteria work and multiply, who have never heard of eugenics in connection with Nazis or anything else, and who will probably have more questions about the mechanics of artificial insemination than thoughts about its social implications. Langone's Genetic Engineering (1978) at least attempts a sketchy background on genetics before taking on the issues, and at the same time gives a better idea of the complexities involved.