It reminds me of some of the explorers' tales of people who were half-human, half some other animal, or of people covered in hair, the first of which may have originated from seeing people riding animals, and the others to various (actual) primates. If humans can make such mistakes, certainly Facebook's AI can be excused for its confusion.
Are you sure those were honest mistakes and not stories for the sake of storytelling? And no, prehistoric ignorance does not justify this system making it to production.
