I find it interesting that certain subtle characteristics of animals can hint at their relationship to other animals.
For example, when you posted the picture of the Roller Bird. I had never seen one before, but something about it reminded me of a kookaburra, so I started looking there.
Often times I'm not even aware of what I recognize in an animal, but general shapes make me think of other animals.
Another example is the African Wild Dog. I though of Hyena, even though I knew that wasn't quite right. So all I did was back up a little bit in the classification tree and start looking for a common point.
Years ago I was involved in Internet design and AI Search algorithms, so it's always been interesting to me how people search for information. The most difficult things to search for (on the net) are things which you recognize, but which you don't have a name for (thus the "name the animal game").
I believe Google is interested in something like this as well. They are testing
an imagelabeler system, although, having played with it, I'm not sure it's going to get them very far.