Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Competive exclusion princple explains why two different species cannot occupy the same niche in the same place for very long.

Answer: What explains why two different species cannot occupy the same niche in the same place for very long?


Question: Cell -> tissue -> organ -> organ system sequence represents the correct levels of organization for multicellular organisms.

Answer: Which sequence represents the correct levels of organization for multicellular organisms?


Question: Vertebrates have evolved more complex digestive systems, with some species having multi-chambered types of stomach organ.

Answer:
Vertebrates have evolved more complex digestive systems, with some species having multi-chambered types of what organ?