The zoo's planners put a lot of thought into the layout of both the animal enclosures (I say enclosures because very few animals are in the traditional barred cages) and the paths the humans would take. Most animals have a pretty big pen with lots of grass and trees surrounding them. There is a continuity between the vegetation in the animal enclosures and the vegetation that lines the wide sidewalks and shades the sitting areas so that there doesn't seem to be much space between where the humans are and where the wild things are.
And the zoo is HUGE! I've been there 5 or 6 times (maybe more) and I STILL don't think I've seen all the animals (although now it's because we choose to hit certain places every time). You would have to be VERY dedicated and move fairly quickly to be able to see everything at the Taipei zoo in one day, if it is even possible. I know that it has to sprawl over several miles because some of the signs pointing you to various exhibits say things like Penguins 530meters, and that's after you've been walking through the zoo for some time.
We went on Monday for Babes' pre-birthday celebration and got a special treat as all of the animals were pretty frisky. We heard lions roar, wolves howl, saw penguins swimming, elephants splashing in the water, giraffe's walking and laying down, it was great!
Anyway, here are some pictures to give you an idea of the scope and prettiness of the zoo.
