I've said on several previous occasions that domestic animals are far from outside the Tet Zoo remit. On the contrary, I find them to be of great interest, and I think that their diversity, evolution and behaviour is something that we should pay attention to more often.
California Chrome lacks a prestigious pedigree, but bears genes that make him born to run
In general, the ability to attribute attention to others seems important: it allows an animal to notice the presence of other individuals (whether conspecifics, prey, or predators) as well as important locations or events by following the body orientation or eyegaze of others.
During the upper Palaeolithic (that is, between 40,000 and 10,000 years ago), prehistoric people in Europe and Asia (and elsewhere) depicted the animals they saw in thousands of piece of cave art.
They're the only species of horse never to be domesticated, and have a fascinating history.