If humans had tails, would we have holes in our trousers, or would we have an extra sleeve to put the tail in?
Apes are tailless so it's kind of hard to image how long, how thick, or how fluffy a humain tail would be.
@jkb Apes (and humans) are more closely related to old world monkeys or circopithecidae which have non-prehensile tails. New world monkeys or atelidae have prehensile tails and are evolutionarily more distantly related to humans. So I would think humans would have non-prehensile tails more similar to macaques and baboons rather than the prehensile tales of spider monkeys. But if we did have tails they would interfere with our upright bipedal gait and big butts.