According to lobbying organization Airlines for America, the number of emotional support animals increased by more than 50% in 2017, reaching 751,000. The airlines’ new policies are presumably an attempt to reduce this number, as well as the passenger upset they can sometimes cause. So American, for instance, bans animals “with tusks, horns or hooves (excluding miniature horses properly trained as service animals.)”

The miniature horses—they couldn’t drag those away.

Clarification: This post was updated to make it clearer that emotional support animals are a separate category from trained service animals. 

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