<span>It reminds the reader of the passage of time! It also reminds you that the events are taking place at night, not during the day.</span>
This statement is false.
Any time a writer paraphrases something he or she read somewhere, it means that he or she is paraphrasing somebody else's words, which means that person has to be credited for it. If the writer reached an opinion independently, then they wouldn't have to cite the source, but otherwise, they do, if they want to avoid plagiarism.
I already used this for a test so you might want to rephrase it:
<span>Scientists have often wondered what bellybutton lint is made up of. An Austrain chemist named Georg Steinhauser decided to find out, and since he had a belly button, he searched himself! He examined over 500 pieces to see what the lint has occupied. He found that it has cotton from clothes, AND dead skin, sweat, basically the stuff our body resists and extracts. Goerg Steinhauser found all this out within a teeny tiny part of your stomach.
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Hope this helps!