A lot of humans need or want braces to fix their crooked teeth, but why do you never see a dog walking down the street with headgear? Our ancient ancestors and mac and cheese may be to blame!

*Correction: Even though hyraxes look similar to rodents, they're actually in the order Hyracoidea, not Rodentia! They're more closely related to elephants and manatees than to mice and guinea pigs.*

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Sources:
https://www.wired.com/2011/11/agriculture-jaw-shape/
http://www.pnas.org/content/108/49/19546
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0117301
https://www.ncbi.nlm.nih.gov/pubmed/19514263
http://www.sciencedirect.com/science/article/pii/S004724840400051X
http://rspb.royalsocietypublishing.org/content/early/2011/06/07/rspb.2011.0971