LogFAQs > #980288076

In Dragon Ball, animal people were all over the place, owing to the manga's gag roots (and Toriyama himself stating that he was still working off of the Dr. Slump energy at the time). However, as the Z portion of the series went on, they started being phased out, to the point where they were practically nonexistent in Super, with the exception of those a part of the main group's circle (Oolong and Puar, particularly).

However, years later, DBZ Kakarot would explain that the animal people were the result of a drug called "animorphaline" that turned humans into animal people, and that the popularity of the drug, which had its peak during Bulma's childhood, fell out of favor as the years passed.