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Use the Following Information to Answer the Question

question 48

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Use the following information to answer the question.
Giardia intestinalis can cause disease in several different mammalian species, including humans. Giardia organisms (G. intestinalis) that infect humans are similar morphologically to those that infect other mammals, thus they have been considered a single species. However, G. intestinalis has been divided into different subgroups based on their host and a few other characteristics.
In 1999, a DNA sequence comparison study tested the hypothesis that these subgroups actually constitute different species. The following phylogenetic tree was constructed from the sequence comparison of rRNA from several subgroups of G. intestinalis and a few other morphologically distinct species of Giardia. The researchers concluded that the subgroups of Giardia are sufficiently different from one another genetically that they could be considered different species. (T. Monis, et al. 1999. Molecular systematics of the parasitic protozoan Giardia intestinalis. Mol. Biol. Evol. 16[9]:1135-44.)

By examining the phylogenetic tree diagrammed in the figure above, what conclusion can you draw about the species G. microti?

Definitions:

Need for Achievement

A psychological drive to excel or meet certain standards of performance.

Stable Aspect

Refers to a characteristic, attribute, or condition that remains consistent and unchanged over time.

Personality

A unique set of emotional, thought, and behavioral patterns that define an individual's personal style of interacting with the physical and social environment.

Physiological Component

The aspects of psychological experience that are rooted in physical processes of the body, such as heart rate or hormone levels.