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Variation uses caminalcules in place of fossil shells.
Some evolutionary change is rapid and discontinuous, and some change is gradual. Fossil patterns can provide clues to the past. Speciation explains evolutionary branching and diversification. This lesson can be presented near the end of a unit which introduces the essential nature of evolution , or it could be used later in the course, in a more detailed treatment of the elements of speciation . Run off materials for handouts and overheads.