Table 1. Representation of major components of natural selection, corresponding components in the laboratory exercise, and potential for misconceptions from the analogy.
Component of Selection & EvolutionLab ComponentPotential for Misconceptions
Shared genotypic backgroundPancake batterThe origin of variation appears to be in the addition of elements (genes) to the organism, rather than in mutation and genetic recombination of existing genes.
Trait variation, de novo genetic diversity, allelesAdded ingredients
Selective environmental pressureTaste preferences, scoringIn nature, genotypes and phenotypes that are more likely to be eaten are less likely to increase in frequency in the population. The opposite is true in this activity.
Traits positively affecting survival are reproduced and thus are more common in the populationIngredient perpetuation after generation 1One common misconception is that individuals, rather than populations, evolve. With only two or three pancake generations, this misconception may be reinforced.
Distribution of traits in a population can change when conditions changeGeneration 2 results from scoring
Species and trait extinction/eliminationLow scoring results in not using the ingredient in subsequent generations