Whenever I encounter an evolutionary argument about why people do something, I w0nder about all the people who don't do it. Like, there is a book called "Why We Run" which, according to a brief review I read, presents a bunch of evolutionary arguments to explain why people enjoy running, and although I hate to judge books by reviews -- well, no, I don't hate it, I do it all the time, I just feel a certain scholarly guilt about it -- I think this argument has a problem explaining why 95% of us don't run.
Which brings me to the "Art Instinct." There is certainly something fundamentally human about art. Just about everyone has aesthetic feelings: we may disagree on what is beautiful, but we all know what it means to think that something is beautiful. We all share some form of the decorative impulse, the desire to make things pretty by putting pleasing designs on them. We adorn our bodies with jewelry, clothes, and tattoos, which seems so natural to us that we forget how weird it would be to see any other animal species doing the same thing.
And yet, the degree to which we care about art and the amount of effort we put into it varies greatly from person to person and culture to culture. Case in point: neolithic Britain. The picture shows what archaeologists are calling the oldest artistic depiction of a person in Britain, and my reaction is, why were neolithic Britains less artistically skilled than my six-year-old son? These were the descendants of people who filled Europe's caves with amazing paintings of animals. What happened? Obviously, the ancient Britons were putting their energies somewhere other than sculpture. They built stone circles on striking moorlands, and large chambered tombs, but they seem to have completely given up representational art. Maybe they had other arts we can't recover, like dance or music. But then again, maybe not.
Art is strange this way. For something so fundamental, it is oddly variable and transient. Some cultures are just vastly better at certain arts than others. Even in a culture that assigns a very high value to certain arts, these may be created by a tiny portion of the population. Other arts may arise in particular aristocratic cultures and become an obsession, for a while, to a tiny group, developing such dense networks of symbols and references that outsiders can only shrug at them. When those groups disappear, their art vanishes with them.