A slow fade
(Display Listing 1.)
In an earlier program named Alice0175d, the penguins became visible immediately when they were called upon to do so.
In this program, the penguins become visible by transitioning from invisible to visible during an elapsed time of one second.
(Display Figure 2.)
The image in Figure 2 was purposely captured in such a way as to catch the front penguin in the transition stage while it was still partially transparent.