Translations:Adventist Youth Honors Answer Book/Nature/Geology - Advanced/8/en

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The sorting could also be a physical phenomenon based on the shape and density of the animal, much as small rocks make their way to the bottom of a sediment, while larger rocks make their way to the top. In this case, the creatures are acting just as the rocks, with mollusks and insects being sorted to the bottom, and tigers and rhinos making their way to the top.