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11 Cards in this Set

  • Front
  • Back
directional stabilization
average value of a trait is shifted in a particular direction (higher or lower)
stabilizing selection
acts to stabilize the population around some average value
disruptive selection
where the environment selects for the two extremes, against the average, splitting the population in two or more types
industrial mechanism
replacement of a light morph by a dark morph in an industrialized area
evolution at or below the level of the species
evolution above the level of the species (orders, classes etc...)
homologous structures
structurally and developmentally similar, even though they may be put to very different uses; derived from a common ancestor
analogous structures
superficially similar, but structurally and developmentally different; may appear similar and may even serve the same purpose
divergent evolution
produces homologous structures. the same bones can be used in many ways, leading to several divergent evolutionary paths - frogs, bats, birds, men, and so on.
convergent evolution
two unrealted lineages converge on a common solution to an evolutionary problem
punctuated equilibruim
new types of fossils often appear abruptly and last through long periods of relative stability until they abruptly disappear