Graduate biology classes geared to the needs of science teachers
Go to the next level in the science you love, find new ways to share the excitement of life science with your students, and problem-solve with other science teachers.
The case of the “camouflage looper”
An important research goal in ecology is to identify the selective pressures that have caused most herbivorous insect species to feed on only a few closely related plant species. Insects are well known for evolving precise color patterns that make them cryptic (difficult to see) when they sit on their preferred host plant. One hypothesis to explain narrow diets is that, in most herbivorous insects, there would be selection against feeding or laying eggs on plants where the insect blends in imperfectly and is consequently more vulnerable to predation. Natural selection should lead to a narrowing of host range to those plant species on which the insect blends in best and is least likely to be eaten by visually hunting predators.
The case of the “camouflage looper” (see photo) may provide evidence supporting this hypothesis. Caterpillars of this species feed on flower petals and while feeding, glue pieces of petals to their backs. As a result, the looper is well camouflaged no matter which plant it feeds on. If natural selection by visually hunting predators is responsible for narrowing of the host plant ranges of herbivorous insects, the camouflage looper should be found on a wide range of host plant species, as it is equally cryptic on every plant. Recent searches in area prairies support this prediction. We have found camouflage loopers feeding on a variety of unrelated plant species, including species in the milkweed, mint, and composite families.
Paul Gross
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The departments of Natural Science and Secondary Education at National-Louis University are teaming up in the 2006-2007 academic year to offer three very special graduate biology courses to high school science teachers.
LAN530 Evolution for Science Teachers I: Microevolution (cross-listed as SEC530) will be offered on Saturdays during the Winter 2007 quarter. The first class will meet Saturday, January 13. Questions? E-mail Paul Gross pgross@nl.edu.
Course description: Participants will update and expand their understanding of microevolution. Topics include mutation, genetic variation, gene flow, genetic drift, natural selection, adaptation, evolutionary ecology, evolution of animal development, neutral evolution, behavioral ecology, and related areas of research. Participants will learn about modern tools for studying microevolution and will examine case studies of natural selection in diverse organisms. Philosophical issues related to conflicts between evolutionary theory and religion will be explored. Teaching methods appropriate to the content will be explicitly addressed in context. Participants will develop classroom activities that adapt evolutionary concepts to the introductory and advanced courses they teach.
Prerequisite(s): Basic knowledge of biology, including some genetics. 3 semester hours
Register
Next up: Cell Biology for High School Teachers, Spring 2007 quarter. For more information, contact Renée Judd, rjudd@nl.edu.
Why study evolution?
by Paul Gross, Ph.D., team teacher for Evolution for Science Teachers I: Microevolution
Winter quarter, 2007
As late as the 1950’s, the study of biological evolution was restricted to particular sub-disciplines of biology like population genetics and paleontology. Evolution seemed only vaguely relevant to such mainstream fields as physiology, cell biology, microbiology, developmental biology, and medicine. Even taxonomy and ecology were largely pre-Darwinian in their scope and methodology.
All this has changed. Evolution is now firmly established as the central paradigm of modern biology. The gradual adoption of an evolutionary perspective has stimulated an explosion of profound insights in areas ranging from population ecology to the study of genome structure. Whole sub-disciplines have sprung up, including ecological genetics, evolutionary systematics, evolutionary medicine, and “evo-devo”, the evolution of development. Our deeper understanding of the mechanics of natural selection has even influenced social sciences like psychology and history. It has become obvious that change is basic to life and that one cannot fully understand present forms without understanding how they got to be that way. Evolution is the study of how organisms change and is therefore basic to all fields of life science.
The incorporation of evolutionary thinking and methodology into the many fields of life science means that science teachers at every level must become comfortable with the central concepts. With this in mind, we are offering a two-part, synthetic course on evolution, geared to the needs of high school science teachers. Part 1, “Microevolution”, will be taught in winter, 2007, and will emphasize the mechanics of evolutionary processes including mutation, natural selection and genetic drift. It will also cover application of evolutionary principles to fields such as ecology, development, medicine, and cell biology. Part 2, which will be offered in winter, 2008, will examine and the evolutionary history of a variety of extant and extinct taxa and the methodology involved in studying phylogenies. Both courses will include sections that will explore ways to develop the concepts in high school science classes.
