lieved in orthogenesis, and only 33.5% of all teachers training of potential biology teachers: (1) organic considered evolution a fact. evolution, (2) genetics, and (3) historical geology. 2. At least one course in the philosophy of science Conclusions should be taken by all prospective teachers. According to the findings of the study, the follow- 3. Departments of biology, botany, and zoology ing conclusions were reached: at colleges and universities should examine critically 1. In terms of number of days spent on the topic the manner in which they present evolution. and amount of material covered, secondary school 4. Textbooks based upon the central, unifying biology teachers of Indiana deemphasized the topic theme of evolution are needed in secondary educa- of evolution. tion. Basic research is needed in the following areas: 1. A nationwide study is needed in order to pro- 2. Although most of the teachers spent little vide a comprehensive view of the status of the prob- time on evolution, large community teachers placed lem of the teaching of evolution. greater emphasis on that topic than did teachers 2. Research is recommended into the problem of associated with small, mostly rural communities. the methodology of teaching evolution.

3. The teachers who attended several NSF in- Downloaded from http://online.ucpress.edu/abt/article-pdf/31/7/458/25800/4442746.pdf by guest on 29 September 2021 stitutes, used BSCS textbooks and materials, and * SELECTED REFERENCES had a large number of credit-hours in biology, were those who placed greater emphasis on evolution in 1. Ginger, Ray. Six days or forever. Boston: Beacon Hill their teaching. Press, 1958, 258 pp. 4. Both large and small community teachers dem- 2. Greene, John C. Darwin and the modern world view. New York: The New American Library, 1963, 126 pp. onstrated serious misunderstandings of and at- 3. Hurd, Paul De Hart. Biological education in American titudes toward evolution which probably resulted secondary schools 1890-1960. Bulletin No. 1, American in a cursory treatment of that topic. Institute of Biological Sciences, 1961, 263 pp. 5. Many of the teachers seemed to be genuinely 4. Riddle, Oscar (Ed.). The teaching of biology in secondary confused about the relationship of evolution to their schools of the United States: A report of results from a questionnaire, Union of American Biological Societies, religious beliefs. 1942, 76 pp. 5. Troost, Cornelius J. An analysis of factors influencing the Recommendations teaching of evolution in the secondary schools of Indiana, Dissertation Abstracts, Volume XXVII, No. 10, April, 1967. 6. White, A. D. A history of the warfare of science with the- 1. To improve teachers' knowledge of evolution, ology in Christendom. New York: Dover Publications, three courses should be a part of the scientific 1960, 415 pp.

BATS disc about three inches in diameter, in the center of which was a glass dispenser where he could Bats are not so blind after all, research at Indiana obtain sugar water. Nearby was another target, a University indicates. Some bat types known to have vertical rectangle about 2/3 by 10 inches, with a keen ears for their own radar-like "echolocation" dispenser for quinine water. system also can see pretty well, it was reported by This bat, after a training period, flew to the Roderick A. Suthers, Indiana University Assistant round target dispensing the sugar water in 83% of Professor of Anatomy and Physiology, and Julia 89 trials. He also scored 100% in picking the round Chase, graduate student. target in eight trials designed to show if the bat's Their bats learned to fly to a visual target of a sense of smell might be involved. In these tests, particular shape to obtain food, in preference to pure water was dispensed at both targets, indicat- another target of similar size but different shape. ing that the sense of smell played no part. The experiments involved conditioning the bats to The position of the targets was frequently in- expect food at one of a pair of slightly different terchanged to eliminate the possibility that the bat patterns, which were dark silhouettes against a was making his choices by direction only. diffusely illuminated background. The arrange- Two fruit-eating bats were tested with melon ment was such that the bat's echolocation system balls. At one target was a ball soaked in sugar and could be of no help in recognizing the patterns. at the other a ball soaked in quinine water. Two species of bats were used, both of them One of these bats scored nearly 90% correctly in noted for their expert navigation by echolocation, choosing between identical rectangular stripes-a but with small eyes heretofore considered to be of verticle one associated with sugared melon and a little use. One species lives on the nectar of flowers horizontal one with quinine. A second fruit-eater and the other on fruit. In testing one of the nectar scored 78% in distinguishing between a three-inch eaters, the experimenters presented him with a square and a circle of the same area.

458 THE AMERICANBIOLOGY TEACHER, OCTOBER, 1969