Re: During the day in Lake Constance, the zooplankton D. hyaline
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16 Sep 2020, 00:14
During the day in Lake Constance, the zooplankton D. hyaline departs for the depths where food is scarce and the water cold. D. galeata remains near the warm surface where food is abundant. Even though D. galeata grows and reproduces much faster, its population is often outnumbered by D. hyaline.
Summary: Conditions for DG is great but the population is less in comparison to DH. So, the option that explains why are DH more/ DG less is the correct answer.
Which of the following, if true, most helps to resolve the apparent paradox?
A. The number of species of zooplankton living at the bottom of the lake is twice that of species living at the surface. TRAP: had to think a lot to reason it out. BUT hey it just says species. There might be some other species of zooplankton.
B. Predators of zooplankton, such as whitefish and perch, live and feed near the surface of the lake during the day. As DG lives in the surface, it shows the chances of being prey to the predators.
C. In order to make the most of scarce food resources, D.hyaline matures more slowly than D. galeata. Assuming maturing and population? We don't know anything about it.
D. D. galeata clusters under vegetation during the hottest part of the day to avoid the Sun’s rays. Irrelevant. It is just additional information about DG
E. D. galeata produces twice as many offspring per individual in any given period of time as does D. hyaline. Does the opposite. So, why DG is still less?