The polluted bacteria and algae interacts with fish and other aquatic wildlife, so they will be negatively impacted by that relationship in this case.
Answer - Theory
Reasoning - Your best bet and term to describe the evolution by natural selection is theory as to still scientific theory/research is still ongoing and changes can be made in a different direction.
The way that partially digested food leaves the body is through the pyloric sphincter.
<h3>What is digestion?</h3>
The term digestion has to do with the breaking down of complex food substances that is taken in by animals during nutrition. Food that is digested will go out of the body in semisolid form.
Hence, way that partially digested food leaves the body is through the pyloric sphincter.
Learn more about digestion:brainly.com/question/1283194
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