Probably the least interesting, esoteric, and useless topic but it's a rabbit hole none the less: the taxonomy of ancestors of modern-day elephants such as the

Probably the least interesting, esoteric, and useless topic but it's a rabbit hole none the less: the taxonomy of ancestors of modern-day elephants such as the Deinotherium (https://en.wikipedia.org/wiki/Deinotherium https://en.wikipedia.org/wiki/Deinotherium). A lot of them look wild and they're interesting to read up on.