12. According to the concept of competitive exclusion,
a. two species cannot coexist in the same habitat.
b. extinction or emigration are the only possible results of
competitive interactions.
c. intraspecific competition results in the success of the
best-adapted individuals.
d. two species cannot share the same realized niche ina habitat.
e. resource partitioning will allow a species to utilize all
the resources of its fundamental niche.
The best answer is d. The competitive
Exclusion Principle states that when the populations of two species compete
for the same limited resources, one population will use the resources more efficiently
and have a reproductive advantage that will eventually lead to the elimination
of the other population.
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Slichter