On 10 December 2019, @MontereyAq tweeted the following sea otter pun: "sea otters imply the existence of land better-nots". The twitter account of the Monterey Bay Aquarium is famous for its way-out puns, but normally I get them. This one I don't understand at all. Can someone here enlighten me?
It's not a very good pun. The opposite of "sea" is "land". "otter" in US is pronounced almost the same as "oughta" ... "ought to", and the opposite of "ought to" is "better not".