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Variation in the Natural World |
Variation is a pervasive characteristic of the natural world. Moreover, genetically based variation provides the raw material for evolutionary change. To understand patterns of the natural world, biologists must be able to recognize the variation among organisms due to a wide variety of factors, including genetic composition, the environment, age, sex, and evolutionary history. Variation among individuals may be either continuous, as in the size and weight of human beings, or it may consist of discrete differences among individuals, such as the number of petals of a flower or the number of legs of an animal.
In this lab you will examine examples of genetically and environmentally caused variation in organisms at the level of the individual, the population, the species, and higher taxonomic levels. You will also measure variation in fin supports of fishes so that you can gain experience analyzing variation in one characteristic of one group of organisms.
Variation within Species
Measuring Variation in Repeated Parts