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Phototropism Misconceptions Letters Phototropism vated plants were originallygiven the PETAwould allow no use of animals. Misconceptions name of a single wild species, yet they Which view-mine or PETA's-is are complex hybrids involving several more likely to constrain Ms. Weber's The science education literature in species, e.g. petunia (Petunia X hy- options as an educator? plant biology is full of misconceptions, brida),geranium (PelargoniumX horto- Ms. Weberasserts that I degrade her so teachers must beware. The wide- rum)and fuchsia (FuchsiaX hybrida). and the teaching profession by ex- spread misconception that phototro- David R. Hershey pressing my concern that teachers pism is merely the bending of plants 6700 BelcrestRd., Apt. 112 might not be able to resist the inces- toward light was repeated by Joseph Hyattsville,MD 20782-1398 sant urge of animal-rights groups to Laferrierein "CompetitiveGravitropic "force their views" on biology educa- and Phototropic Stimuli in Coleus" tors. I did not write that, nor did I (ABT,September 1993). Like gravitro- References imply it. Unfortunately, while Ms. pism, phototropism can be positive or Weber was busy misrepresenting my Bailey, L.H., Bailey, E.Z. & Bailey views in her letter negative. Many roots and some vine to The American Downloaded from http://online.ucpress.edu/abt/article-pdf/56/1/6/46411/4449733.pdf by guest on 25 September 2021 stems exhibit negative phototropism HortoriumStaff. (1976). Hortus third: Biology Teacher, PETA and other by bending away from light. If vine A concisedictionary of plantscultivated groups were busy as well-constrain- stems were not negatively photo- in the UnitedStates and Canada.New ing Ms. Weber'soptions through pub- tropic, they would grow away from York:MacMillan. lic education campaigns and through solid objects and would not climb Firn, R.D. (1990). Phototropism.Jour- actual and proposed legislation that nal of BiologyEducation, walls or grow into buildings through 24, 153-157. limits the use of animals in the class- cracks. Another common phototro- room. Much of this has been possible pism misconception is that auxin gra- Animals in Education because of the naivete and false senti- dients cause phototropism (i.e. the ment I tried to highlight in my article. Cholodny-Went theory). Firn (1990) Last, Ms. Weber asserts that, "The considers that the typical textbook ac- Dear Editor: teaching of biology needs to be count of phototropism is badly out- I was not surprised by the letters brought into the computer age." I dated and reviews how the Cholodny- from Susan Weber and Sue Brebner agree, but intellectually bankrupt in- Went theory of phototropism is (ABT,October 1993) in response to my struction remains such even on the incompatible with recent research. A May 1993 article "Animals in Educa- computer;it is simply more flashy and 1992 scientist forum, "What remains tion: Are We Prisoners of False Senti- expensive. I am happy to have Ms. of the Cholodny-Wenttheory?" (Plant, ment?" Strong statements on contro- Weber or anyone else use alternatives Cell and Environment,15, 757-794), re- versial issues generally elicit strong to dissection, including computer veals the diversity of opinion on the responses. Ms. Brebner,education di- models, so long as those models are topic. rector of PETA, has, however, pro- sound, and so long as one does not Laferriere's phototropism/gravitro- duced an even more thorough misrep- believe that computers actually can pism experimentwould be much more resentationof contraryviews than one substitute for the experience of dissec- realistic if fluorescent, rather than in- normallyexpects from PETA,demon- tion-a claim promoted by PETA candescent light was used. The main stratingnicely that ignoranceand zeal- and, problem with incandescent light is otry rarely combine to salutaryeffect. unfortunately, by the NABT mono- graph. that a plant located 30 cm from a single Ms. Brebneraccuses me of declaring My article makes this position bulb receives less than 1%of full sun- that some animals are "bad," and clear, as well as my position that pre- light, which is too low for growth of therefore open to human "exploita- college students should be free to opt even a shade-loving plant such as co- tion." I did not write that, but then out of dissections for good and suffi- cient leus. Also, is it fair to have 100%of PETAis not best known for allowing reasons. How this translatesinto natural gravity for gravitropism but accuracy to inform its arguments. I my "wanting to take her choice of <1% of natural sunlight for phototro- simply was trying to point out that the methodology away from her," only Ms. pism? Incandescent light is also poor natural world is not as benign as the Weber knows. She certainly has for phototropic research because it American public-distanced as it is not made the connection in her letter. contains a low percentage of the blue from nature-has come to believe. Ms. Brebner "fears for the biology wavelengths that activate the photo- PETAand other radical animal rights curriculumin any school where (my) tropic response. Plants can be placed groups easily exploit this naivete. influencemight be felt."Should PETA's view 2 cm from fluorescent bulbs, allowing Ms. Weber is even more confused of the naturalworld prevail, and adequate light for healthy growth of than Ms. Brebner.She accuses me of should Ms. Weber and others con- coleus; and fluorescent light has a trying to constrain her options as a tinue to buy it without reflection,there greater percentage of blue wave- teacher. My article was clear on this will be nothing to fear. Indeed, there lengths. issue: Teachersshould have the option will be little left in the curriculumthat we A final error involves the scientific to use dissection or alternatives, so can continue to call biology. name for coleus. Coleusblumei is not long as the alternativesare sound. She Joseph D. McInerney the correct name for the cultivated holds up the NABT monograph as a Director, BSCS coleus, which is a complex hybrid monument to responsible use, yet she 530 N. Tejon St. named ColeusX hybridus(Bailey et al. fails to acknowledge that for PETA Suite 405 1976). Several of our commonly culti- there is no such thing. Groups such as ColoradoSprings, CO 80003-4720 6 THEAMERICAN BIOLOGY TEACHER, VOLUME 56, NO. 1, JANUARY1994 .
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