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A big part of being a human is that you get progressively more gross as the day goes on. Various parts start stinking, hair grows all over your face, you're touching who-knows-what... luckily for all of us, someone a long time ago decided to invent hygiene! Otherwise we'd have to lick ourselves like cats!

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[Definition] 

History of hygiene https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2542893/ [Trivia Question] Pelagic thresher sharks visit blue-streaked cleaner wrasse stations https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0014755 https://www.fisheries.noaa.gov/feature-story/sharks-rays-and-climate-change-impacts-habitat-prey-distribution-and-health 

[Fact Off] 

Bronze Age ivory lice comb with Canaanite language 

https://jjar.huji.ac.il/sites/default/files/jjar/files/jjar2_art4_lachish_p76-119_2022-10-12_01.pdf https://www.sciencefocus.com/news/4000-year-old-head-lice-comb-found-inscribed-with-phrase-using-the-alphabet https://www.sciencenews.org/article/canaanite-comb-lice-israel-alphabet 

Tampon Task Force & menstrual hygiene https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5436965/ https://catalystjournal.org/index.php/catalyst/article/view/28788/_9 https://www.youtube.com/watch?v=KYXUQDzSg4o&feature=youtu.be https://srh.bmj.com/content/early/2023/07/03/bmjsrh-2023-201895 https://www.eurekalert.org/news-releases/997629 

[Ask the Science Couch] 

Antiperspirant aluminum compounds - how they work & are they harmful 

https://cen.acs.org/articles/90/i27/Deodorants-Antiperspirants.html https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3813027/ https://www.webmd.com/breast-cancer/features/antiperspirant-facts-safety https://www.smithsonianmag.com/history/how-advertisers-convinced-americans-they-smelled-bad-12552404/ 

[Butt One More Thing] 

Mandrills teach their children hygienic behaviors to avoid peri-anal parasites 

https://royalsocietypublishing.org/doi/10.1098/rspb.2022.2349 https://www.eurekalert.org/news-releases/979546