Science Question for Friday, December 11th, 2015
Abandoned cornfields have been the sites of investigations concerning ecological succession, the orderly progression of changes in the plant and/or animal life of an area over time (see Figure 1).
(Note: The plants are ordered according to their appearance during ecological succession.)
During the early stages of succession, the principal community (living unit) that dominates is the pioneer community. Pioneer plants are depicted in Figure 2.
The final stage of ecological succession is characterized by the presence of the climax community, the oak-hickory forest. Figure 3 depicts the gradual change from pine to hardwoods.
Figures adapted from Eugene P. Odum, Fundamentals of Ecology. ©1971 by Saunders College Publishing/Holt, Rinehart, and Winston, Inc.
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On the basis of the data depicting the gradual change from pine forest to an oak-hickory forest, after 100 years, as the density of the pine trees:
A. increases, the density of the oak-hickory trees increases.
B. increases, the density of the oak-hickory trees decreases.
C. decreases, the density of the oak-hickory trees increases.
D. decreases, the density of the oak-hickory trees decreases.
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