Researchers studying groupies in Trinidad found that guppies in streams with high predation reproduced earlier and more frequently. Which of the following is most important in driving the guppies to change their life history in face of predation?
A. The guppies are an equilibrium species.
B. The guppies are an opportunistic species.
C. Density-independent factors affects the guppy populations.
D. Density-dependent factors affects the guppy populations.
E. Sexual selection affects the guppy populations.
Ans: B. The guppies are an opportunistic species.
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A. G1 B. G2 C. S D. M E. meta-
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