The cannibalism and interspecific predationlab utilizes both T. thermophila and T. vorax. Morphogenetic change is addressed by observing the T. vorax shift from microstome to macrostome form. As part of the lab, stomatin, the transformation inducing subtance produced by T. thermophila is isolated using simple techniques that can easily be carried out in high school classrooms. The change in morphology is obvious even under relatively low magnification. The lab can be used to address, chemical induction of morphological changes, evolutionary differences among different species within the same genus, and, since the macrostome forms consume their own species as well as (preferably) other Tetrahymena species, inter- and intra-specific predation. The use of inexpensive digital cameras to record morphological changes and predation events adds enormously to student interest and enthusiasm for this exercise.
Organisms; Relationship of Structure to Function; Mechanisms of Evolution; Population dynamics; Diversity of Organisms; Growth and Survival of Organisms; Diversity and Adaptation of Organisms; Interorganismal Relationships; Species Variation
Next Generation Science Standards Relationships
NYS Science Curriculum Guideline Relationships
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- Ryals PE, Bae S, Patterson CE. 1999. Evidence for early signaling events in stomatin-induced differentiation of Tetrahymena vorax. J.Eukaryot.Microbiol. 46 (1):77-83.
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