The Following Questions Refer to Figure 27.1

question 3

Multiple Choice

The following questions refer to Figure 27.1.
In this eight-year experiment, 12 populations of E. coli, each begun from a single cell, were grown in low-glucose conditions for 20,000 generations. Each culture was introduced to fresh growth medium every 24 hours. Occasionally, samples were removed from the populations, and their fitness in low-glucose conditions was tested against that of members sampled from the ancestral (common ancestor) E. coli population.

Figure 27.1
-Which term best describes what has occurred among the experimental populations of cells over this eight-year period?

• A) microevolution
• B) speciation
• C) adaptive radiation
• D) sexual selection
• E) stabilizing selection

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Definitions:

Australopithecines

A group of extinct hominins closely related to humans, known from fossil remains found in Eastern Africa.

Homo Sapiens

The species to which all modern human beings belong and the only extant member of the genus Homo.

Spreading Outside

The process by which a phenomenon or entity expands beyond its original boundaries or limits.

Africa

The world's second-largest and second-most populous continent, known for its rich biodiversity and cultural heritage.