My son asked me this after watching Finding Nemo. He thought it improbable because as he suggested, what would be large enough to choke a whale and therefore necessitate having a uvula to help cause a protective gag reflex? Excellent question, Son.
We googled it: "Do whales have a uvula?"--no, whales do not have uvulas (uvulae?). In fact very few animals do--humans and apes being some who do.
Then we looked up uvula and found that there is no consensus as to the purpose of the uvula. It may not be to elicit a gag reflex. The uvula secretes saliva, so perhaps it helps coat the throat; it is responsible for the formation of some sounds in some languages, so perhaps evolved as our languages did; it closes off the nasopharynx so that you don't constantly blow milk out of your nose. No one knows for sure what it's for.
What is it for??? I really want to know now.
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