The potential for the picture was there when I saw this giraffe flick out his tail with the one on the horizon present, but I'd missed it initially. I waited for what felt like an eternity before he did it again all the more hoping the distant one would stay put. Eventually, the tail flicked out, everything else stayed in place, and I got my picture.
And I almost gave up myself, from fatigue from holding the heavy 400mm lens in position for the whole duration.
There's more about the book and competition at WPOTY Portfolio 21.