The fetus.

Anyways, do you see that bump looking part, just by what looks like the leg? ... Do fetus start to grow a tail, then stop, or, am I just being fruitless?

Just as all humans have vagina's at one time during
their stage as a fetus, all humans _do_ have tails.
But humans have tails before they develop into a
fetus. The embryo's tail is absorbed by the fetus
as it grows into and becomes a fetus.

m04r.