This seems reasonable, but the current behavior (using the order the user explicitly passed us) is also reasonable. One concern about sorting here is that while z-order will be respected in this list, they will all be drawn above any existing artists.

Can you also add at API change note (as anyone who is relying on the behavior of drawing in the order they passed the artists in will be broken) and update the docs for FuncAnimation to make this behavior clear?

Alternately, would updating the docs to be clear that the artists are drawn in the order the user passed them in (as the user has full control of that).

Just my personal opinion here: I would say that since blitting is used for fast operations one should not slow it down by introducing a sorting step. In the end, if the user needs the artists to be sorted they can do it in the animating function.

I seriously doubt that the sorting would impact the performance measurably. I also think that respecting the relative zorder is the right thing to do.

Thanks @jdollichon !