3.Using the graph below, explain why the graphs of the two
species usually rise and fall in unison.
As the hare popluation rises, there is
a greater food supply for the lynxes, which feed primarily on hares. As the
lynx population increases to a certain point, the hare population begins to
fall because of the predation. When the hare population decreases past a certain
point, the lynx population too will decrease. The cycle would begin again. Be
aware however, that the hare population is also influenced by its food supply,
or the number of plants. The rabbits increase when food is more available, and
will decrease when food is in short supply. They follow this cycle whether there
are lynxes are not. Thus this situation is more complicated than might first
appear.
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Slichter